Article

Effects of Platelet-Rich Plasma on the Healing of Autologous Bone Grafted Mandibular Defects in Dogs

April 2006
Journal of Oral and Maxillofacial Surgery 64(3):443-51

April 2006
64(3):443-51

DOI:10.1016/j.joms.2005.11.016

Source
PubMed

Authors:

This study was undertaken to describe both radiographically and with histomorphometric analysis the effect platelet-rich plasma (PRP) has on immediate autologous bone grafts in a dog model. Thirteen dogs comprised the study. Twelve adult dogs received bilateral inferior mandibular border defect resections measuring 2 cm x 1 cm. The right defect was immediately grafted with milled autologous iliac corticocancellous bone along with 2 cc of PRP that was developed in a standardized fashion. The left side was immediately grafted with the same amount of autologous iliac corticocancellous bone placed without PRP. Three animals were sacrificed at 1, 2, 3, and 6 months. A thirteenth dog underwent bilateral inferior border resections with only PRP placed in the right defect, and nothing placed in the left defect. This dog was sacrificed at 6 months. Ten and 3 days before sacrifice all animals received 10 mg/kg body weight tetracycline intravenously. At sacrifice, grafts along with adjacent native bone were harvested, fixed, radiographed, and processed for epifluorescence analysis. Analysis of digitized radiographs indicated that at 1 and 2 months the non-PRP grafts were significantly more dense than the PRP grafts, and at 3 and 6 months there was no significant difference. Histomorphometric analysis showed that at 1 and 2 months there was significantly less grafted bone and more new bone in the PRP grafts than in the non-PRP grafts. At 3 and 6 months there was no difference in the amount of grafted bone or new bone between the PRP and non-PRP grafts. Histology of the control dog showed incomplete bony healing at 6 months, suggesting that this was a critical sized defect. The bone apposition rate for all times in the PRP and non-PRP graft sites did not significantly change. PRP appeared to enhance early autologous graft healing. However, after 2 months this effect is no longer significant. The early enhanced healing occurred by increasing the amount of non-viable grafted bone that was removed and increasing the amount of new bone that was formed. PRP did not change the rate at which new bone was formed, and no increase in trabecular density was realized in these grafts.

Optimization of a rapid one-step platelet-rich plasma preparation method using syringe centrifugation with and without carprofen

Article

Full-text available

May 2020
BMC Vet Res

Background: Carprofen and platelet-rich plasma (PRP) are widely used in small animal clinical practice. Separation layers have been used during blood centrifugation to increase platelet yield. The objectives of this study were to (1) identify the optimal centrifugation force for the one-step PRP preparation, (2) determine whether there is an advantage to using carprofen in one-step PRP preparation, and (3) compare platelet morphology from one-step PRP preparation with and without carprofen. We hypothesized that injectable carprofen (emulsion formula) could be used successfully as the separation layer in PRP preparation. Results: Samples from 14 healthy dogs were used to determine the optimal centrifugation force using one-step PRP preparation in a disposable syringe without carprofen, with forces set at 300, 500, 700, 900, 1100, 1300, and 1500 xg for 5 min. Optimum centrifugation force, plasma volume, and platelet concentrations of one-step PRP preparation were found and recovered at 900 xg, 1.9 ± 0.28 ml, and 260.50 ± 58.39 X 103 cell/μl, respectively. Samples from 12 healthy dogs were used to determine the optimal force (with forces set at 300, 500, 700, and 900 xg) for 5 min using one-step PRP preparation with carprofen. Optimum centrifugation force, plasma volume, and platelet concentrations for one-step PRP preparation with carprofen were found and recovered at 500 xg, 0.62 ± 0.16 ml and 948.50 ± 261.40 X 103 cell/μl, respectively. One-step PRP preparation with carprofen increased the platelet yield from baseline by 1.76 and 4.95 fold, respectively. Samples from 3 healthy dogs were used to observe platelet morphologies after centrifugation by scanning electron microscopy. Images of platelets on glass slides from both preparation methods revealed pseudopods emerging from the margins of the discoid platelets. Conclusions: One-step PRP centrifugation both with and without carprofen increased the platelet yield, but using carprofen (emulsion formula) as a separation layer resulted in a higher platelet yield. The clinical usefulness of PRP products from these methods should be further investigated.

Effect of platelet-rich plasma on orthodontic tooth movement in dogs

Article

May 2017

Objectives: To evaluate the effect of platelet-rich plasma (PRP) on the rate of orthodontic tooth movement. Methods: The sample comprised six skeletally mature male mongrel dogs. The maxillary second premolar in each dog was extracted bilaterally. PRP was prepared and injected around the first premolar in one randomly selected maxillary quadrant while the other quadrant served as the control. Coil springs (150 g) were used to distalize the first premolars for 63 days using TAD as anchorage. Results: Total maxillary tooth movement was significantly faster on the experimental than on the control side. Conclusion: Local injection of PRP in the present animal study resulted in accelerated orthodontic tooth movement with no obvious clinical or microscopic side effects.

Mapping global trends in canine platelet-rich plasma research: a bibliometric analysis using Scopus database

Article

Jun 2022
Indian Vet J

Platelet-rich plasma (PRP) is a category of platelet concentrate containing a supraphysiological concentration of platelets in a small volume of plasma. The present study was undertaken to analyze the global trends in canine PRP research and to gain a better understanding of the ongoing research trends. The literature search was performed using the Scopus database, and the extracted data was further analyzed in terms of different variables. The data was then visualized in the form of bar diagrams and bibliometric maps. The systematic search identified 125 documents published between 1975 and 2021 based on inclusion and exclusion criteria. A fluctuating increase was observed in total publications between 2003 and 2021, with the peak in 2018 indicating slow progress in the interest towards canine PRP research in the research community. The Research Support Foundation of the State of São Paulo funded the most studies in PRP research. In addition, the United States emerged as the most productive country and Universidade Estadual Paulista Júlio de Mesquita Filho as the most productive institute/university. The major findings of the top ten cited publications on canine PRP research are also discussed in this paper.

The role of bone marrow aspirate cells in the management of atrophic mandibular fractures by mini-invasive surgical approach: Single-institution experience

Article

Jan 2017
J CRANIO MAXILL SURG

Purpose: The treatment of fractures involves addressing the biology of fracture repair and the mechanical stability of fracture fixation. Traditionally it has included the addition of bone graft to enhance healing. New advances in the understanding of the cellular and molecular mechanisms of fracture repair have led to the use of growth factors to accelerate bone healing. This study aimed to assess the advantages of autologous stem cell use for atrophic mandibular fracture treatment in comparison to standard technique. Materials and methods: A total of 35 patients (14 male and 21 female) were treated for fractures of atrophic mandibles between January 2011 and December 2014. Surgical technique provided mini-invasive open reduction with or without immediate homologous bone graft, while selected patients received autologous bone marrow aspirate cell grafts in addition to the standard treatment. Demographic data and details of treatment and outcomes were recorded. Results: Patients were categorized according to the use of autologous stem cells, leaving 17 patients treated with standard technique and autologous stem cells (Group A) and 18 treated with standard osteosynthesis only (Group B). Of the 35 patients, 26 had bilateral fractures; most patients had significant medical co-morbidities. Immediate bone graft was used in 37.1% of patients (7 in group A and 6 in group B). Complications occurred in 5 patients (14.3%). Two patients in group B (11.1%) showed non-union of the fracture. One patient in group A (5.8%) and one patient in group B (5.5%) showed wound dehiscence and were treated conservatively; one patient in group B had a local infection (5.5%), one out of 35 (2.8%), that was managed by prolonged antibiotic treatment. Conclusions: Despite the advanced age and medical co-morbidities of the vast majority of patients, mini-invasive open approach with autologous bone graft ensures a fast and excellent recovery. Moreover, the management of atrophic mandibular fractures by bone marrow aspirate cells is a safe and useful procedure which has a lower complication rate when compared to standard technique.

Socket preservation using freeze-dried bone allograft with and without plasma rich in growth factors in dogs

Article

Full-text available

Sep 2016
Dent Res J (Isfahan)

Background: Plasma rich in growth factors (PRGF) and freeze-dried bone allograft (FDBA) are shown to promote bone healing. This study was aimed to histologically and histomorphometrically investigate the effect of combined use of PRGF and FDBA on bone formation, and compare it to FDBA alone and control group. Materials and Methods: The distal roots of the lower premolars were extracted bilaterally in four female dogs. Sockets were randomly divided into FDBA + PRGF, FDBA, and control groups. Two dogs were sacrificed after 2 weeks and two dogs were sacrificed after 4 weeks. Sockets were assessed histologically and histomorphometrically. Data were analyzed by Kruskal-Wallis test followed by Mann-Whitney U-tests utilizing the SPSS software version 20. P < 0.05 was considered statistically significant. Results: While the difference in density of fibrous tissue in three groups was not statistically significant (P = 0.343), the bone density in grafted groups was significantly higher than the control group (P = 0.021). The least decrease in all socket dimensions was observed in the FDBA group. However, these differences were only significant in coronal portion at week 4. Regarding socket dimensions and bone density, the difference between FDBA and FDBA+PRGF groups was not significant in middle and apical portions. Conclusion: The superiority of PRGF+FDBA overFDBA in socket preservation cannot be concluded from this experiment.

Bone Augmentation in Rabbit Tibia Using Microfixed Cobalt-Chromium Membranes with Whole Blood and Platelet-Rich Plasma

Article

Full-text available

Jul 2015

Background: Bone augmentation is a subject of intensive investigation in regenerative bone medicine and constitutes a clinical situation in which autogenous bone grafts or synthetic materials are used to aid new bone formation. Method: Based on a non-critical defect, Co-Cr barrier membranes were placed on six adult Fauve de Bourgogne rabbits, divided into two groups: whole blood and PRP. Three densitometric controls were performed during the experiment. The animals were euthanized at 30, 45, 60, and 110 days. The presence of newly formed bone was observed. Samples for histological studies were taken from the augmentation center. Results: External and internal bone tissue augmentation was observed in almost all cases. Significant differences between PRP- and whole blood-stimulated bone augmentation were not observed. At 60 days, bones with PRP presented higher angiogenesis, which may indicate more proliferation and cellular activity. Conclusion: PRP activates the bone regeneration process under optimized conditions by stimulation of osteoblast proliferation after six weeks, when a significant difference in cellular activity was observed. Membranes could stimulate bone augmentation at the site of placement and in the surrounding areas.

The effect of piezosurgery with cvd tip in osteotomy in rat parietal bone: histologic and histomorphometric analysis

Article

Full-text available

Mar 2015

Objective : The aim of this study was to compare the response of bone tissue in osteotomy under piezosurgery using a CVD tip in rat parietal bone in contrast with the standard protocol using low-speed tungsten burs. Material and Methods : A bone defect model was created in parietal bone of 20 male Wistar rats using CVD tip and drill. Five animals were sacrificed after 3, 7, 14 and 28 days and the bone containing the defects was submitted to the histologic and histomorphometric analysis. The results of histomorphometry were statistically analyzed using RM ANOVA with a significance level of α = 0.05. The results were still subjected to Tukey's multiple comparison test. Results : The results showed statistically significant difference (p <0.05) between the two types of treatment in the analyzed periods. Piezosurgery promoted slower and more precise cut with less bone loss and less bleeding during surgery, promoting conditions for a faster repair compared to the traditional method of osteotomy, fewer inflammatory cells, faster bone formation, cleaner surgical wound in the experimental group in all periods. Conclusion : It was concluded that the use of CVD tip in piezosurgery was proven to be valid for osteotomy, with more precise cuts, less tissue damage, fewer pronounced inflammatory response and faster bone formation in the early periods when compared with low-speed tungsten burs.

Histomorphometric, radiographic and biomechanical analyses of platelet rich plasma associated with autogenous bone graft

Article

Full-text available

Nov 2014

Objective: The aim of this study was to evaluate the effectiveness of platelet rich plasma with and without autogenous bone graft in the bone repair of surgical defects in rabbit tibias. Materials and Methods: In this research, 25 adult male rabbits were used. Two defects have been performed in each tibia, divided into four groups: control (C = defect naturally left to heal by clot formation), autogenous (A = bone defect + autogenous graft), PRP (PRP = bone defect + PRP) and autogenous + PRP (PRPA = bone defect + autogenous graft + PRP). All the defects were covered with a dPTFE membrane. Five other animals were sacrificed at 15, 30, and 60-day postoperatively. The pieces containing the defects were processed for histological and histomorphometric analysis. Other five animals were sacrificed after 30 and 60 days and submitted to biomechanical analysis, and all the specimens were sent to the radiographic evaluation of optical density. Results: The biomechanical, radiographic, and histomorphometric results showed larger resistance, optical density, and improving bone formation in the groups A and PRPA when compared with the groups C and PRP. Conclusion: This study showed there was not an improvement in the radiographic, mechanical, and bone formation parameters when PRP was used individually or associated to the autogenous bone graft.

Bone augmentation in rabbit tibia using microfixed cobalt-chromium membranes with whole blood, tricalcium phosphate and bone marrow cells

Article

Full-text available

Mar 2015
Int J Clin Exp Med

To assess bone augmentation based on a non-critical defect, 1.5 mm deep cobalt-chromium (Co-Cr) barrier membranes were placed on seven adult California rabbits with three different grafting situations: whole blood, whole blood with tricalcium phosphate (TCP), and TCP mixed with bone marrow cells. Macroscopic assessment of the animals was performed once a week and densitometric studies were performed once a month. Three months post-surgery, after detaching the membranes, tibias were sectioned and followed the routine laboratory processing for decalcified sections, with inclusion in paraffin and staining by hematoxylin and eosin technique. Bone augmentation was observed for each animal, even sometimes over the Co-Cr membranes. Compact bone was mostly observed for every situation, with a higher cellular activity on those samples with bone grafts. This could be due to the presence of graft remains at the growth area. It could be concluded that blood supply to the site providing growth factors by the blood clot formation, and the placement of an osteoconductive non-resolvable membrane that favors osseoinduction, may be sufficient elements to achieve bone augmentation in a period of three months in rabbit tibia.

Reconstruction of the mandible with an autogenous corticocancellous bone graft and fibrin glue: An animal experiment

Article

Full-text available

Jan 2012

This paper reports on an experimental animal study evaluating a method of mandibular reconstruction in dogs using autogenous corticocaneclous bone graft and fibrin glue. Eight animals underwent a resection at the mandibular body and primary reconstruction was carried out using osteosynthesis plates and screws. The defect was bridged with an autogenous particulate bone graft from the anterior iliac crest. To accelerate bone healing, fibrin glue (FG) was mixed with particulate bone graft. The hypothesis of this study was based on the presumption that bone healing, in segmental reconstruction of the dog mandible with a particulate cancellous bone graft mixed with FG, would be successful. All dogs had eventful healing. The histological results were less favorable with regard to bone remodeling than the results obtained in similar experiments with a particulate corticocancellous bone graft.

Effect of local administration of injectable platelet-rich fibrin on root resorption during orthodontic tooth movement in dogs

Article

Full-text available

Nov 2023
Dent Res J (Isfahan)

Background This study aimed to assess the effect of local administration of injectable platelet-rich fibrin (i-PRF) on root resorption during orthodontic tooth movement in dogs. Materials and Methods This animal study was conducted on 4 adult male mongrel dogs. The right and left maxillary first premolars of the dogs were extracted, and a Nickel-Titanium closed coil spring was used to connect the canine to the second premolar with 150 g load. Next, 0.5 cc of i-PRF was injected in one quadrant of the maxilla around the second premolar into the periodontal ligament. The other quadrant of the maxilla served as the control group and received saline injection. Injections were performed at 1, 21, and 42 days, and the dogs were sacrificed after 63 days. Histological sections were prepared and cementum resorption, secondary cementum formation, and number of cementoblasts and cementoclasts were compared between the two groups by the Friedman test, Wilcoxon test, and Mann–Whitney test (α = 0.05). Results The mean percentage of cementum resorption (17.75% ± 5.56%) and secondary cementum formation (14.50% ± 6.65%), and the mean number of cementoblasts (10.25 ± 2.36) and cementoclasts (9.75 ± 4.71) were insignificantly higher in the i-PRF group than the corresponding values (13.75% ± 4.34%, 8.50% ± 2.88%, 7.75 ± 1.25, and 6.50 ± 3.10, respectively) in the control group (P > 0.05). Conclusion Administration of i-PRF insignificantly increased the percentage of cementum resorption, secondary cementum formation, number of cementoblasts, and number of cementoclasts.

The radiological study of using fabricated calcium hydroxide from quail eggshell and plasma-rich fibrin for reconstitution of a mandibular bone gap in dogs

Article

Full-text available

Jan 2024

Therapeutic applications of canine platelets and their derivatives: a narrative review

Article

Nov 2023
TOP COMPANION ANIM M

Platelets contain a multitude of growth factors and play a crucial role in physiological processes such as thrombogenesis, tissue repair, and angiogenesis. As a result, platelet-derived products have significant potential for efficient utilization in the realm of regenerative medicine due to their therapeutic and biological attributes. Numerous studies have already substantiated the therapeutic viability of platelets in various canine ailments. The existing literature indicates a substantial surge in the clinical application of canine platelets, positioning platelet-derived products as a viable alternative to conventional therapeutic agents. Platelet concentrates, including platelet-rich plasma and platelet-rich fibrin are commonly used as a therapeutic modality in clinical cases. These therapeutic derivatives exhibit effectiveness in tissue regeneration and can serve as complementary therapies. Notably, they offer a cost-effective and easily accessible therapeutic option, which has demonstrated its benefits in chronic inflammatory disorders such as osteoarthritis and tendinitis, ophthalmic conditions, wound healing, and mandibular injuries in canine patients. The broad spectrum of therapeutic effects displayed by platelets is providing researchers with novel perspectives for crafting therapeutic models in future investigations. This review centers on exploring the therapeutic potential of canine platelets across diverse disorders. Further exploration into platelet products, encompassing their preparation and applicability in canine medicine, is imperative. These inquiries hold the promise of unveiling fresh horizons for the domain of regenerative medicine.

8.Evaluation of The Role of Hydroxyapatite Nano Gel as Filling

Article

Full-text available

Jan 2023

EJVS Volume 54 Issue 1 Pages 1-11

Article

Full-text available

Sep 2022

A LARGE size bone defect is a challenging problem in orthopedic. This trial focuses on investigating the effects of Hydroxyapatite Nano gel as filling materials for accelerating the healing of repaired tibial bone defects in dogs. The experiment included 18 healthy dogs which was randomized divided into two equal groups, 9 of each. The experimental bone defect was created at (2.5 by 0.7cm ) in both groups. In the control group, the same bone piece is reimplanted at the experiment defect and fixed with Cerclage wire. In the second group, a deproteinized lamb rib at (2.4 by 0.6cm) was used to repair the bone defect, and the graft segment was fixed with Cerclage wire, and the repaired defect was supported with hydroxyapatite Nano gel. The animals were monitored clinically, grossly and radiologically on days 14, 30 and 60. The defect completely healed with no apparent changes on day 60 post-operatively. Radiographically, in the control group on day 60, there was a faint lucent line around the fixated bone segment with minimal cortical thickening and irregularities denoting late chronic periosteal reaction and callus formation and near complete healing with the surrounding area whereas in the treatment group, the callus formation was superior in comparison with control group and there are some cortical irregularities denoting chronic periosteal reaction. We demonstrate that using hydroxyapatite nano gel as an additive to the defective bone fills the voids, accelerates the healing process. Radiological analysis showed superior healing and callus formation in hydroxyapatite nano gel group with xenobone graft.

Level of Evidence on Platelet-rich Plasma in Plastic Surgery

Article

Full-text available

Apr 2021

Background: Despite the increased popularity of platelet-rich plasma (PRP) in plastic surgery, there is no detailed analysis on the level of evidence on PRP use in plastic surgery. As the number of applications of PRP in plastic surgery increases, it is important for plastic surgeons to understand the scientific and validated evidence behind its use. Therefore, we performed a literature review to identify current level of evidence on platelet-rich plasma in plastic surgery. Methods: We performed a computerized search of platelet-rich plasma in plastic surgery using the MEDLINE, Cochran Library, and EMBASE databases. Data regarding the type of study, PRP application, and outcomes were collected. Then, the level of evidence was assigned using the American Society of Plastic Surgeons Level of Evidence Rating. Results: Our search identified 105 articles, and about 78.1% of studies were lower-quality studies: 37 level-III articles (35.2%), 32 level-IV articles (30.5%), and 13 level-V articles (12.4%). There were only 6 level-I articles and 17 level-II studies. Level-I studies were on facial rejuvenation using a laser, carpal tunnel release, cleft lip repair, trauma wounds, breast reconstruction using latissimus dorsi, and hair regrowth. Conclusions: Our review of the literature shows that the level of evidence on PRP use in plastic surgery is low (21.9%). Nevertheless, we believe level-III to level-V studies are still valuable, as performing high-level quality studies in plastic surgery is difficult due to variability in surgical techniques, experiences, and materials.

The Effect of Autologous Platelet Concentrates on Maxillary Sinus Augmentation: A Meta-Analysis of Randomized Controlled Trials and Systematic Review

Article

Full-text available

Jun 2020
BMRI

Introduction: To assess the efficacy of the autologous platelet concentrates (APCs) combined with autologous bone or bone substitute for the maxillary sinus floor lifting by a meta-analysis. Materials and methods: Electronic databases (PUBMED, Web of Science, EMBASE through OVID, and Cochrane Library) were searched until Dec 31, 2019, and only randomized controlled trials (RCTs) in English were identified. Outcome variables included histologic evaluation, the implant stability quotient values, and radiographic evaluation. Data were analyzed by Revman5.3; the estimate of effect sizes was expressed as the 95% confidence interval; and the risk of bias was evaluated using the Cochrane Collaboration tool. Results: 11 RCTs involving 141 patients (214 sites) were included in our meta-analysis, which indicated that the differences in the percentage of contact length among newly formed bone (2.61%, 95% CI, -1.18% to 7.09%), soft tissue area (-0.15%, 95% CI, -0.54% to 0.24%), and residual bone substitute material (-5.10%, 95% CI, -10.56% to 0.36%) in the APC group lacked statistical significance. Besides, there was the same effect on the implant stability quotient (ISQ) values of APC group who underwent implant placement 4 months after sinus augmentation and control group who received implant placement 8 months after sinus augmentation (-0.48, 95% CI, -1.68 to 0.72). No significant effect of APCs on the bone density was found (1.05%, 95% CI, -1.69% to 3.82%). Conclusions: The use of APCs in sinus augmentation may be further shorten the time required for bone graft maturation and allow earlier implant placement, but cannot enhance the bone formation in the long term. It is not currently recommended for routine use APCs as an osteoinductive material to bone grafting in sinus augmentation.

Osteoclast recruitment and polymorphism during the healing process in dental implant surgery

Article

Full-text available

Feb 2019

The use of bioactive factors to enhance bone regeneration. A narrative review

Article

Jan 2019

Aim This review critically appraises the available knowledge on the pre‐clinical and clinical use of bioactive factors for bone regeneration in the cranial and maxillo‐facial area. Materials and Methods The use of growth factors, amelogenins and autologous platelet concentrates (APCs) for bone regeneration was reviewed in a systematic manner. More specifically, preclinical and clinical studies on ridge preservation, alveolar ridge augmentation, regeneration of peri‐implant defects and sinus augmentation models were considered. Results Amongst different bioactive factors, the highest pre‐clinical and clinical evidence of a positive effect on bone formation is associated with BMP‐2 and the lowest with amelogenins. While APCs seem to accelerate clinical healing and reduce postoperative discomfort, there is insufficient and contrasting evidence of a significant effect on hard tissue regeneration for the different clinical applications. Conclusions Although there is increasing evidence that bioactive factors might enhance the bone regeneration process, the great heterogeneity of the available studies and the limited number of RCTs do not allow to draw robust conclusions. Issues that still need to be investigated include the optimal carriers for bioactive agents (direct vs. indirect), the dosage, the timing of administration, as well as the possibility of combining different agents to promote synergistic effects. This article is protected by copyright. All rights reserved.

Autologous Platelet-rich Plasma after Third Molar Surgery

Article

Full-text available

Jul 2017

Aim and Objective The aim of this study is to compare the efficacy of autologous platelet-rich plasma (PRP) in the third molar impactions, with respect to: pain, swelling, healing, and periodontal status distal to the second molar in patients who need surgical removal of bilateral impacted mandibular third molars. Materials and Methods Twenty-five patients of both sexes aged between 16 and 60 years who required bilateral surgical removal of their impacted third molars and met the inclusion criteria were included in the study. After surgical extraction of the third molar, primary closure was performed in the control group, whereas PRP was placed in the socket followed by primary closure in the case group. The outcome variables were pain, swelling, wound healing, and periodontal probe depth that were follow-up period of 2 months. Quantitative data are presented as mean. Statistical significance was checked by t-test. Results There was a difference in the pain (0.071) and facial swelling (0.184), reduction between test and control on day 3, but it was not found to be significant. Periodontal pocket depth (0.001) and wound healing (0.001) less in case group compared with the control group was found to be significant. Conclusion The use of PRP lessens the severity of immediate postoperative sequelae and decreases preoperative pocket depth.

Autologous platelet-rich plasma induces bone formation of tissue-engineered bone with bone marrow mesenchymal stem cells on beta-tricalcium phosphate ceramics

Article

Full-text available

Nov 2017
J Orthop Surg Res

Background The purpose of the study is to investigate whether autologous platelet-rich plasma (PRP) can serve as bone-inducing factors to provide osteoinduction and improve bone regeneration for tissue-engineered bones fabricated with bone marrow mesenchymal stem cells (MSCs) and beta-tricalcium phosphate (β-TCP) ceramics. The current study will give more insight into the contradictory osteogenic capacity of PRP. Methods The concentration of platelets, platelet-derived growth factor-AB (PDGF-AB), and transforming growth factor-β1 (TGF-β1) were measured in PRP and whole blood. Tissue-engineered bones using MSCs on β-TCP scaffolds in combination with autologous PRP were fabricated (PRP group). Controls were established without the use of autologous PRP (non-PRP group). In vitro, the proliferation and osteogenic differentiation of MSCs on fabricated constructs from six rabbits were evaluated with MTT assay, alkaline phosphatase (ALP) activity, and osteocalcin (OC) content measurement after 1, 7, and 14 days of culture. For in vivo study, the segmental defects of radial diaphyses of 12 rabbits from each group were repaired by fabricated constructs. Bone-forming capacity of the implanted constructs was determined by radiographic and histological analysis at 4 and 8 weeks postoperatively. Results PRP produced significantly higher concentration of platelets, PDGF-AB, and TGF-β1 than whole blood. In vitro study, MTT assay demonstrated that the MSCs in the presence of autologous PRP exhibited excellent proliferation at each time point. The results of osteogenic capacity detection showed significantly higher levels of synthesis of ALP and OC by the MSCs in combination with autologous PRP after 7 and 14 days of culture. In vivo study, radiographic observation showed that the PRP group produced significantly higher score than the non-PRP group at each time point. For histological evaluation, significantly higher volume of regenerated bone was found in the PRP group when compared with the non-PRP group at each time point. Conclusions Our study findings support the osteogenic capacity of autologous PRP. The results indicate that the use of autologous PRP is a simple and effective way to provide osteoinduction and improve bone regeneration for tissue-engineered bone reconstruction.

Plasma Rich in Growth Factors Stimulates Proliferation and Mineralization in Mesenchymal Stem Cells from Human Bone Marrow

Article

Jun 2017

Plasma rich in growth factors(PRGF) can be rapidly obtained from patient blood. PRGF has been used in regenerative therapy for soft tissue and bone formation, and represents a new and potentially useful adjunct in oral and maxillofacial bone reconstructive surgery. However, few studies have investigated the biological functions of PRGF in bone regeneration. Human mesenchymal stem cells(hMSC) isolated from human bone marrow have the capacity to commit to multiple cell types such as the osteoblastic lineage, and have been widely applied in tissue engineering studies in recent years. The aim of this study is to evaluate the effects of PRGF for osteogenic differentiation in hMSC. PRGF was prepared from whole blood centrifuged at 460×g for 8 min. PRGF F2 was incubated with 10% calcium chloride solution at 37℃ for 1 h to trigger platelet activation and growth factor release. Activated PRGF Fraction 2 was centrifuged at 3,000×g for 15 min, and the supernatant was then isolated. We examined the effects of soluble factors in PRGF on proliferation and mineralization in hMSC culture supplemented with PRGF. The proliferation of hMSC was increased in osteogenic induction medium(OIM) supplemented with PRGF. Alkaline phosphatase activity increased in hMSC by PRGF. Staining for alizarin red S and von Kossa was strong in hMSC supplemented with PRGF. These results suggest that PRGF is able to promote bone generation.

Bone Marrow Aspirate Concentrate versus Platelet Rich Plasma to Enhance Osseous Integration Potential for Osteochondral Allografts

Article

Jun 2017

Fresh osteochondral allograft (OCA) transplantation is an attractive treatment option for symptomatic articular cartilage lesions in young, healthy patients. Since a lack of OCA bone integration can be a cause of treatment failure, methods for speeding and enhancing OCA bone integration to mitigate this potential complication are highly desirable. This study sought to determine and compare the potential of bone marrow aspirate concentrate (BMC) and leukoreduced platelet rich plasma (PRP) to repopulate the osseous portion of an OCA with cells and deliver osteogenic proteins. It was hypothesized that BMC would have significantly higher colony forming units (CFUs)/mL and seed the osseous portion of OCA with more cells than PRP. Finally, we hypothesized that the media of BMC and PRP treated OCAs would have significantly higher concentrations of osteogenic proteins compared with negative control OCAs. Cylindrical OCAs (n = 36) created from tissue stored for 21 days were treated with BMC (n = 12) or PRP (n = 12) obtained for 6 dogs, or left untreated as a negative control (n = 12). After treatment, OCAs were cultured for 7 or 14 days. Media were collected for analysis of osteogenic biomarker concentration. Samples of each BMC and PRP were tested for CFU concentration. On day 7 or 14, the grafts were assessed for cell surface adhesion and penetration using fluorescent microscopy. Significant differences in CFU and media biomarker concentration the between groups were determined using one-way analysis of variance (ANOVA) and Tukey's post-hoc test with the significance set at p < 0.05. Only OCAs saturated with BMC had viable cells detectable on the osseous portion of the allografts at day 7 and 14 of culture. BMC samples had a significantly higher (p = 0.029) CFU/mL compared with PRP samples. At day 3 and/or 7 of culture, the concentration of several osteogenic proteins was significantly higher in both BMC and PRP samples. Autogenous BMC can be used to deliver both a cell population and osteogenic proteins that may improve healing of the osseous portion of the OCA clinically.

Platelets Activation and Liver Transplantation

Article

Full-text available

Jan 2017

Transient thrombocytopenia is a common phenomenon after living donor liver transplantation (LDLT), and severe thrombocytopenia after LDLT is associated with graft loss and poor patient outcomes. The various causes of thrombocytopenia include bone marrow hematopoiesis failure due to decreased thrombopoietin (TPO) production in the injured liver, platelet destruction associated with splenomegaly, and the activation and consumption of platelets due to various forms of thrombosis, including disseminated intravascular coagulation (DIC), thrombotic microangiopathy (TMA), and venous thromboembolism (VTE). The observation of biomarkers such as soluble platelet glycoprotein VI (sGPVI), TPO, von Willebrand factor (VWF), VWF propeptide (VWFpp), and disintegrin-like and metalloproteinase with thrombospondin type-1 motifs member 13 (ADAMTS13) is useful in the evaluation of the mechanisms of thrombocytopenia in patients who undergo LDLT. The presence of these biomarkers, including sGPVI, ADAMTS13, VWF and VWFpp, suggests that platelet activation occurs in the early phase of LDLT and that vascular endothelial cell injury occurs on postoperative days 7-14.

Evaluation of the Effect of Platelet-Rich Plasma on Alveolar Wound Healing in Rats Evaluación del Efecto del Plasma Rico en Plaquetas en la Cicatrización de Heridas Alveolares en Ratas

Article

Full-text available

Jan 2017

NOVELLI, M. D.; CORRÊA, L.; DE SOUSA, S. C. M. & LUZ, J. G. C. Evaluation of the effect of platelet-rich plasma on alveolar wound healing in rats. Int. J. Morphol., 35(1):251-258, 2017. SUMMARY: Opinions about the clinical utility of platelet-rich plasma (PRP) vary, as a large number of experimental studies have questioned its efficacy. The purpose of this study was to evaluate the effects of PRP on experimental alveolar wound healing in rats. Fifty young adult male Wistar rats were divided in control and PRP groups and submitted to extraction of the right maxillary incisor. In the PRP group, blood was collected by cardiac puncture, and the socket was filled with a PRP gel. Animals were euthanized after 1, 3, 7, 14 and 30 days. Histological and histomorphometric analyses were performed at each experimental time point. Semiquantitative histological analysis showed that the PRP group exhibited significantly more collagen-matrix deposition and less bone-matrix formation in the socket than did the control group from 7 to 30 days. Histomorphometric analyses showed that the PRP group also exhibited lower bone-tissue areas than the control group at 7 (p=0.0250) and 14 days (p<0.0001), but at 30 days, no significant difference between the groups was observed. In the present study, PRP did not enhance alveolar wound healing, and PRP-treated rats exhibited low rates of bone deposition during the intermediate phases of alveolar socket repair.

Evaluation of the Effect of Platelet-Rich Plasma on Alveolar Wound Healing in Rats

Article

Full-text available

Mar 2017

Opinions about the clinical utility of platelet-rich plasma (PRP) vary, as a large number of experimental studies have questioned its efficacy. The purpose of this study was to evaluate the effects of PRP on experimental alveolar wound healing in rats. Fifty young adult male Wistar rats were divided in control and PRP groups and submitted to extraction of the right maxillary incisor. In the PRP group, blood was collected by cardiac puncture, and the socket was filled with a PRP gel. Animals were euthanized after 1, 3, 7, 14 and 30 days. Histological and histomorphometric analyses were performed at each experimental time point. Semiquantitative histological analysis showed that the PRP group exhibited significantly more collagen-matrix deposition and less bone-matrix formation in the socket than did the control group from 7 to 30 days. Histomorphometric analyses showed that the PRP group also exhibited lower bone-tissue areas than the control group at 7 (p=0.0250) and 14 days (p

Plasma rich in growth factors stimulates proliferation, migration, and gene expression associated with bone formation in human dental follicle cells

Article

Full-text available

May 2016
J DENT SCI

Background/purpose: Plasma rich in growth factors (PRGFs), which is prepared from autologous blood from patients, has been reported with regards to bone regeneration for dental implants. Human dental follicle cells (hDFCs) have the capacity to commit to multiple cell types such as the osteoblastic lineage. The aim of this study is to evaluate the effects of PRGFs for mineralization in hDFCs. Materials and methods: PRGFs was prepared from whole blood centrifuged at 460g for 8 minutes. hDFCs isolated from the dental follicle with collagenase/dispase were cultured with growth medium or osteogenic induction medium (OIM) containing PRGFs or fetal bovine serum. Concentrations of the growth factors were examined using an enzyme-linked immunosorbent assay kit. A cell migration assay was used for two-dimensional movement. Gene expressions were examined with real-time polymerase chain reaction using a DyNAmo SYBR Green quantitative polymerase chain reaction kit. Results: The platelet concentration in PRGF Fraction 2 was 2.14-fold higher than in whole blood. White blood cells were not detected in PRGFs. Transforming growth factor-β levels were higher than insulin-like growth factor-1, platelet-derived growth factor-AB and -BB, and vascular endothelial growth factors in PRGF Fraction 2. Proliferation and migration by hDFCs increased in OIM supplemented with PRGFs in a dose-dependent manner and were higher in hDFCs cultured in OIM plus 10% PRGFs compared with OIM plus 10% fetal bovine serum. PRGFs upregulated the gene expression of type I collagen, osteomodulin, alkaline phosphatase, bone morphogenic protein-4, and transforming growth factor-β in hDFCs. Conclusion: PRGFs may promote bone regeneration due to it including high levels of growth factors.

Micro CT Evaluation of Bone regenerative capacity in rats claverial bone defect using platelet rich fibrin with and without beta tri calcium phosphate bone graft material

Article

Full-text available

May 2016

Walid Ahmed Abdullah

Aim: To compare bone regeneration in noncritical rat calvarial bone defects filled with platelet-rich fibrin (PRF), alone or combined with beta-tricalcium phosphate (β-TCP), using micro-computed tomographic (MCT) evaluation. Animals and methods: Two calvarial bone defects were created in each of 45 male Sprague–Dawley rats (age: 20–22 weeks, weight: 350–450 g), using a dental trephine with an external diameter of 3 mm. The 90 defects were randomly allocated among three groups, each containing 30 unilateral defects in a total of 30 rats. Defects in the control group were allowed to heal spontaneously. Defects in the PRF group received PRF alone. Defects in the PRF/β-TCP group received PRF mixed with β-TCP in a 50⧹50 percentage. Nine animals (three per group) were killed after 1, 2, 3, 4, and 6 postoperative weeks, and 18 calvarial defects from each period were analyzed for new bone formation and bone mineral density using MCT. Results were compared by a one-way Analysis of Variance with the POST HOC Least Significant Difference test. Results: The volume and mineral density of bone formed in the control group were significantly different from those of the other two groups. Greater bone regeneration was observed in defects receiving PRF with β-TCP compared to defects receiving PRF alone in the first 2 weeks (P 0.005). Conclusion: The addition of β-TCP to PRF significantly improved bone regeneration in the first 2 weeks after surgery. Although the differences between results with and without the addition of β-TCP to PRF were statistically insignificant from weeks 3 to 6, it was nevertheless apparent that the group receiving the combination showed better results. We suggest a synergistic mechanism for this effect.

Evaluation of the efficacy of platelet-rich plasma and platelet-rich fibrin in alveolar defects after removal of impacted bilateral mandibular third molars

Article

Full-text available

Apr 2016

Aim and objectives: This study attempted the evaluation of the efficacy of platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) in alveolar defects after removal of bilateral mandibular third molars. Materials and methods: A total of 30 patients reporting to Department of Oral and Maxillofacial Surgery and having bilateral mandibular third molar impaction in both male and female aged between 18 and 30 years were included in this study. PRF and PRP were placed in extraction site and recalled at 2(nd), 4(th), and 6(th) month postoperatively. Data were statistically analyzed using IBM SPSS software for Windows, version 19.0. IBM Corp., Armonk, NY, USA. Results: This study showed decreased probing depth in PRF group compared to PRP and control one. This signifies a better soft tissue healing of extraction sockets with PRF as compared to the PRP and the control group and increase in the bone density highlights the use of PRP and PRF certainly as a valid method in inducing hard tissue regeneration. Conclusion: This study indicates a definite improvement in the periodontal health distal to second molar after third molar surgery in cases treated with PRF as compared to the PRP group and control group. Hence, PRP and PRF can be incorporated as an adjunct to promote wound healing and osseous regeneration in mandibular third molar extraction sites.

Investigation of a pre-clinical mandibular bone notch defect model in miniature pigs: clinical computed tomography, micro-computed tomography, and histological evaluation

Article

Full-text available

Feb 2016

Objectives: To validate a critical-size mandibular bone defect model in miniature pigs. Materials and methods: Bilateral notch defects were produced in the mandible of dentally mature miniature pigs. The right mandibular defect remained untreated while the left defect received an autograft. Bone healing was evaluated by computed tomography (CT) at 4 and 16 weeks, and by micro-CT and non-decalcified histology at 16 weeks. Results: In both the untreated and autograft treated groups, mineralized tissue volume was reduced significantly at 4 weeks post-surgery, but was comparable to the pre-surgery levels after 16 weeks. After 16 weeks, CT analysis indicated that significantly greater bone was regenerated in the autograft treated defect than in the untreated defect (P=0.013). Regardless of the treatment, the cortical bone was superior to the defect remodeled over 16 weeks to compensate for the notch defect. Conclusion: The presence of considerable bone healing in both treated and untreated groups suggests that this model is inadequate as a critical-size defect. Despite healing and adaptation, the original bone geometry and quality of the pre-injured mandible was not obtained. On the other hand, this model is justified for evaluating accelerated healing and mitigating the bone remodeling response, which are both important considerations for dental implant restorations.

Colocación de implantes de oseointegración en mandíbulas con reabsorción severa utilizando la técnica “tent pole” serie de casos

Article

Jun 2013

La rehabilitación protésica mandibular implanto-soportada actualmente es una excelente opción de tratamiento para pacientes edéntulos, ya que brinda adecuada estabilidad y mejor acceso para la higiene. La reabsorción del reborde alveolar mandibular ocurre en sentido vertical y horizontal. Muchos de estos pacientes presentan alturas alveolares que oscilan entre los 3 mm y 8 mm, aumentando el brazo de palanca de la prótesis con especto al soporte mandibular.La opción de aumentar el reborde alveolar en altura y grosor mediante la técnica “Tent Pole”, evita futuras complicaciones como fracturas patológicas que sin duda complicarían el manejo. Utilizando este método no solo se logra un aumento de grosor y altura alveolar, sino que también evita la contaminación de los injertos que ocurre a través del abordaje intraoral (1-4). A continuación, presentamos una serie de tres casos utilizando esta técnica.

Immunohistochemical Evaluation of Fibronectin and Tenascin Following Direct Pulp Capping with Mineral Trioxide Aggregate, Platelet-Rich Plasma and Propolis in Dogs' Teeth

Article

Full-text available

Jul 2015

The aim of the present study was to evaluate the expression of fibronectin (FN) and tenascin (TN) after direct pulp capping (DPC) in dogs' teeth with either mineral trioxide aggregate (MTA), Propolis or Platelet-rich plasma (PRP), by means of immunohistochemistry. A total of 48 sound molars and premolars with mature apices from four dogs, were included. The teeth were randomly divided into 4 groups according to the material used for DPC: PRP, Propolis, MTA, and glass-ionomer (as the negative control group). Each group was divided into two 7-day and 30-day subgroups. The teeth were restored at the same session. The animals were sacrificed at the mentioned time intervals and the expression of FN and TN in each test group and between each time intervals was assessed with Wilcoxon and Mann-Whitney U tests, respectively. The Kruskal-Wallis test was used to compare FN and TN staining among the test groups. The significance level was set at 0.05. The amount of FN in the MTA group in the 30-day interval was significantly higher than the 7-day interval; however, there were no significant differences among the other groups. The amount of TN in the MTA and Propolis groups in the 30-day interval was significantly higher than that in the 7-day interval; no recognizable difference was observed in the other groups. Moreover, the difference in expression of FN and TN in the 7-day interval was not significant in the experimental groups. Nevertheless, the difference was significant in the 30-day interval, with the highest and lowest expressions belonging to the MTA and glass-ionomer groups, respectively. Based on the results of the present animal study, MTA is still a better choice for direct pulp capping.

Platelet-Rich Plasma: A Study of the Variables that May Influence Its Effect on Bone Regeneration

Article

Jul 2015
CLIN IMPLANT DENT R

Currently, the use of platelet-rich plasma in bone regeneration is a real option, although more than one opinion has alerted us to the absence of clinical benefits. Analysis of the factors able to modify the characteristics of the platelet preparation obtained by Curasan, Plasma Rich in Growth Factors (PRGF), Platelet Concentrate Collection System (PCCS) and SmartPrep systems, relating them to the type of clinical application and the final bone regeneration achieved. A search was conducted in PubMed using the keywords "platelet-rich plasma," "PRP," "platelet rich growth factors," and "oral bone regeneration." Four widely accepted protocols for the obtention of PRP (above) were analyzed. Any clinical studies with controls, using the four preparation protocols and with a 4 to 6 weeks follow-up period were compared. The protocols were also grouped according to the type of PRP application: PRP-alone, with bone, or with bone substitutes. Bone regeneration was not achieved in any of the cases using PRP obtained by Curasan and PCCS systems, whereas PRP obtained by SmartPrep achieved it only in one in three published cases and PRGF in one in six. Based on the poor results observed in current literature, the use of PRP in oral surgery cannot be recommended. © 2015 Wiley Periodicals, Inc.

Effects of Plasma Rich in Growth Factors on Bone Formation in Rat Calvaria

Article

Jan 2015

Plasma rich in growth factors (PRGF) had been used in regenerative therapy such as soft tissue and newly bone formation. However, there has been little basic research into the efficacy of PRGF in bone regeneration. In this study, we evaluated the efficacy for new bone formation by transplantation of PRGF onto rat calvaria. The osteogenic potential was evaluated by histologic findings, immunohistochemistry and bone formation analyzed with micro-computed tomography (micro-CT). PRGF was prepared by centrifugation of rat whole blood (WB), and then was activated using 10% calcium chloride solution. The activated PRGF transplanted within a polytetrafluoroethylene (PTFE) tube was transplanted onto calvarial bone of rats. Histological observation demonstrated that PRGF group showed newly formed bone in a wide range. Immunohistochemistry showed Runx2, Osterix, Bone Alkaline Phosphatase (BAP) and Osteocalcin expressed in PRGF group during the early stage of bone formation. Micro-CT showed that PRGF group promoted an increase in bone volume which compared to control group. We concluded that PRGF has more capacity for bone regeneration, and PRGF may be useful in bone regeneration treatment.

The inflammatory response of the pulp after direct capping with platelet-rich plasma and enamel matrix derivative: A controlled animal study

Article

Full-text available

Jan 2014

Aims: To evaluate the inflammatory response of the exposed pulp of incisor teeth in rats after direct pulp capping, using platelet rich plasma (PRP), enamel matrix derivate (EMD), mineral trioxide aggregate (MTA) and calcium hydroxide (Ca(OH)2). Methods: The study was conducted on 36 Wistar albino rats with a total of 144 incisor teeth. The pulps of 96 teeth of the rats were perforated and capped with different agents. Serving as the positive control group, the pulps of 24 teeth were only perforated and capped without capping agents, whereas the pulps of 24 teeth were us- ed as the negative control group without being perfo- rated (without any process). The research was ended with the extracting of the teeth on the 7th day - 28th day. The teeth were taken to the routine and histolo- gical follows; cross sections were prepared and pain- ted with hematoxylen & eosin. All of the sections were evaluated in terms of inflammatory reaction by his- tologic analysis taken by light microscope. Statistical analysis was used. The normal distribution of all data was tested with the Mann Whitney U and the differences between the groups were analyze dusing Kru- skal Wallis test at 0.05 level. Results: There are no statistically significant differences in terms of inflam- mation type and necrosis among the treatment groups on 7 days’ post capping. However, improved inflam- matory cell accumulation, hyperemia and lowest ne- crosis were observed from the samples treated with PRP (p < 0.05). Conversely, the EMD group indicated that the criteria of inflammation scores and hyperemia were higher in the 28th day (p < 0.05). Conclusions: Most of cells accumulating in the PRP group and most necrosis were seen in the EMD group. These new PRP materials might serve as pulp capping bio- materials to induce initial healing response in the fu- ture.

Micro-computed tomography and histomorphometric analysis of the effects of platelet-rich fibrin on bone regeneration in the rabbit calvarium

Article

Apr 2015
ARCH ORAL BIOL

Nonvascularized Reconstruction

Chapter

Aug 2022

Bony reconstruction of the oral cavity can be performed using a variety of methods: autograft, allograft, and xenograft. Prior to selecting any grafting technique, the defect must be analyzed and the appropriate graft can be chosen by assessing maxilla vs. mandible, anatomic sub-region, amount and type of soft tissue envelope, and ultimate reconstructive goals. Once these have been assessed, the surgeon can select the grafting technique. The gold standard continues to be autograft. Each donor site has indications and limitations based on type of tissue, type of bone and volume of harvest, as well as limitations due to positioning requirements of the patient. These autograft sites are all well tolerated though the surgeon must also take into account systemic factors and surgical history of the patient. With proper assessment and surgical technique, the utilization of the grafts is usually limited by the creativity of the surgeon.KeywordsMandibular reconstructionMaxillary reconstructionNonvascularized graftsAICGPICGTibia graftCranial graftPlatelet-rich plasma

Percutaneous autologous bone marrow injection in the treatment of delayed union of long bone fractures after definitive fixation

Article

Full-text available

Mar 2022

The purpose of this study was to assess the results of percutaneous autologous bone marrow injection in the treatment of delayed union of long bone fractures after definitive fixation. It has been a gruelling job for the orthopaedic surgeons to deal with the delayed union after definitive fixation due to the lack of patient compliance for reoperation like classical bone grafting technique for delayed union and non-union, unfavourable fracture site morphology for external compression, post-operative surgical wound issues etc., The percutaneous autologous bone marrow injection is a reasonable choice in this scenario for the treatment of Delayed union of long bone fractures after definitive fixation. The study was performed in the department of orthopaedics Assam Medical College and Hospital, Dibrugarh, Assam, India for a period of 2 years from July 2019 to June 2021. A total of 23 patients were taken with delayed union of long bone fractures after definitive fixation. These 23 patients were treated with percutaneous autologous bone marrow injection and followed up for 6 months. The results were evaluated on the basis of clinico-radiological criteria of union, and found to be excellent in 60.86% (14/23), good in 17.39% (4/23) and poor in 21.73% (5/23) cases. The percutaneous autologous bone marrow injection provides cellular stimulation and promotes fracture healing without the necessity for opening the fracture site. Hence it is an effective method to bring about successful outcome of delayed union of long bone fractures after definitive fixation without adding any significant complication to the patient and the fracture site.

Reconstruction of Severely Atrophic Mandible by Installing Dental Implants Using the Modified “Tent Pole” Technique: Case Report

Article

Full-text available

Sep 2018

Patients who use full dental prostheses for long periods of time usually experience bone resorption in the alveolar process and in keratinized mucosa. This can cause instability, low prosthetic retention, and subsequent loss of function. Treating a patient with a severely atrophic mandible is quite challenging due to the low bone height and thickness, potentially impairing rehabilitation, aesthetics, and functional recovery. Several techniques are used to reconstruct major vertical defects for the installation of dental implants. Among these is the “tent pole” technique, which features low morbidity and generally produces good results in the form of increased height of the alveolar ridge bone. Herein we describes a patient with a severely atrophic mandible, reconstructed using a plate and dental implants. We employed a modified “tent pole” technique using an autogenous graft of the iliac crest and without use of platelet-rich plasma concentrate. Our results indicate that the modified tent pole technique using the iliac crest graft, and without use of platelet-rich plasma, is a safe and effective method for achieving mandibular reconstruction while restoring function, aesthetics, and the patients’ quality of life.

Platelet and Transforming Growth Factor Beta 1 Concentrations in Platelet-rich Plasma in Dogs

Article

Full-text available

Aug 2020

Assessment of Quality of Platelet-Rich Plasma Produced With Desktop Centrifuge and Comparison With Standardized Commercially Available Platelet-rich plasma

Article

Aug 2020

Aims: The aim of this study was to assess the quality of platelet-rich plasma (PRP) produced by in-house desktop centrifuge method and compare it with that of standardized commercial PRP. Materials and methods: REMI desktop centrifuge was used to prepare PRP and to compare with standardized commercial PRP by calculating the quantity of platelets using Beckman Coulter cell counter in 10 PRP samples and assessing the morphological quality of platelets using JEOL JEM transmission electron microscope (TEM). Statistical analysis used: The t test for platelet count in desktop PRP with the test value of therapeutic PRP was 12.618. The P value was <0.001, which was significant statistically. The data followed a normal distribution in normal Q-Q plot for platelet count in desktop centrifuge. So the test samples were not much deviated. Results: The platelet count was lesser than that of standardized commercial PRP. When viewed under JEOL JEM transmission electron microscope, the α granules in platelets were intact and the morphological quality of the PRP was good. Conclusions: With this study, we have determined that the morphological quality of PRP produced by the in-house desktop centrifuge method is comparable to that of standardized commercial PRP. Though the quantity of platelets was less than 1 million cells/μL, the clinical results were good with desired bone formation, thereby providing good avenue for further research.

Efficacy of Platelet-Rich Plasma in Enhancing the Osteogenic Potential of Bone Graft in Oral and Maxillofacial Region

Article

Apr 2020

Background Platelet-rich plasma (PRP) has been a breakthrough in the stimulation and acceleration of bone and soft tissue healing. It represents a relatively new biotechnology that is part of the growing interest in tissue engineering and cellular therapy.MethodsA prospective study was carried out in 50 patients. The cases were selected randomly in the age group of 8–50 years who needed bone grafts for alveolar cleft defects and surgical defects following removal of osteolytic jaw lesions. They were divided into study group with autologous PRP and control group without PRP. Bone density was calculated as per Hounsfield scale preoperatively and post-operatively for both the groups.ResultsThere was significant difference in the Hounsfield units at 06 months and 12 months post-operatively in both the groups showing good amount of bone regeneration. The preoperative volume of the defect and the post-operative volume of the regenerated bone were statistically analysed. The mean V2 was 0.7652 cc for the study group, whereas for control group, it was 0.4840 cc. The volume ratio for study group was 0.9070 and for control group was 0.6740. This showed greater bone regeneration in the study group. The results were statistically significant for both the groups.ConclusionPRP is a new application of tissue engineering and a developing area of interest for clinicians and researchers. It is a storage vehicle for growth factors, especially PDGF and TGF-b, both of which influence bone regeneration, and also eliminates the concerns about immunogenic reactions and disease transmission. PRP does enhance the healing of bone grafts in the maxillofacial region as shown by the increase in the density of bone.

Apport des techniques biologiques en chirurgie implantaire : le rôle des facteurs de croissance

Thesis

Oct 2007

Janel Cécile

Les implants endo-osseux représentent à l'heure actuelle une approche thérapeutique des plus intéressantes en dentisterie mais leur mise en place est souvent compromise par une quantité insuffisante d'os dans la zone où ils doivent être implantés. Dans de telles situations, il est nécessaire d'accroître chirurgicalement le volume osseux disponible avant la mise en place des implants. Ces dernières années, les avancées dans la connaissance du fonctionnement des facteurs de croissance ont poussé les chercheurs à leur trouver des applications cliniques en implantologie. Le but de notre étude est de déterminer si l'utilisation des facteurs de croissance dans les procédures d'augmentation osseuse permet d'améliorer la régénération osseuse et l?ostéointégration des implants dans l'os nouvellement formé. Après quelques rappels sur la cicatrisation osseuse et l'ostéointégration, notre travail s'intéresse aux différents facteurs de croissance impliqués dans la régénération osseuse. Puis, nous nous attardons sur deux applications cliniques des facteurs de croissance en implantologie : la rhBMP-2 et les concentrés plaquettaires. En nous basant sur les études animales et humaines portant sur ces deux applications, nous analysons leurs effets sur la régénération osseuse et l'ostéointégration des implants. Nous concluons sur l'avenir des facteurs de croissance en chirurgie implantaire, qui parait très prometteur, mais aussi sur la nécessité de réaliser des études plus poussées et sur un plus long terme avant d'envisager une utilisation clinique de routine de ces agents biologiques.

Comparison study between plasma rich in growth factors and platelet-rich plasma for osteoconduction in rat calvaria

Article

Jul 2017

Objective Plasma rich in growth factors (PRGF) and platelet-rich plasma (PRP) can be rapidly obtained from patient blood. They are a new and potentially useful adjunct in oral and maxillofacial bone repair or regenerative surgery. The aim of this study was to compare the possibility of new bone formation using PRGF and PRP. Methods The osteogenic potential with transplantation of PRGF or PRP onto rat calvaria was evaluated by histologic examination and microCT. PRGF or PRP was prepared by centrifugation of rat whole blood (WB). First, the cells in the blood product were counted; there were no leukocytes in PRGF, and PRP included leukocytes. PRGF contained higher levels of TGF-β1 and PDGF-BB than PRP. Furthermore, PRGF or PRP was transplanted onto calvarial bone of rats. Results MicroCT showed that PRGF promoted an increase in bone volume when compared to PRP. Histological observation demonstrated that the PRGF group showed newly formed bone in a wide range. In addition, the PRP group showed numerous inflammatory cells compared to the PRGF group in HE-stained specimens. This suggests that PRP might delay bone regeneration due to the inflammatory response. Conclusions PRGF has more availability for bone regeneration than PRP, and PRGF may be useful in bone regeneration treatment.

OSSEOINTEGRATED IMPLANTS PLACEMENT IN SEVERLY RESORBED MANDIBLES USING THE "TENT POLE" TECHNIQUE: CASE SERIES

Article

Jun 2013

Mandibular rehabilitation with implant-supported prostheses is now an excellent treatment option for edentulous patients because it provides increased stability and improved oral hygiene. Mandibular alveolar resorption occurs in vertical and horizontal vectors. There are patients presenting mandibular alveolar heights between 3 and 8 mm which unfavorably increases the prosthetic level arm. The option to increase the alveolar height and thickness before implant placement avoids complications like pathological fractures which compromises the results. By using the "Tent Pole" technique the surgeon achieves an increase of alveolar width and height, and by the way preventing contamination of the grafts through communication with the oral cavity, (1-4). We present a series of three cases using this technique.

Tissue Engineering in Maxillofacial Surgery

Article

Jan 2009

Henning Schliephake

Orofacial rehabilitation after ablative surgery or trauma is one of the main objectives of oral and maxillofacial surgery. Many treatment strategies in this field thus fall into the realm of reconstructive surgery. A standard measure in the field of oral and maxillofacial reconstruction is the use of autogenous grafts for the replacement of tissue parts, which is associated with a significant increase in surgical effort and morbidity. The growing understanding of tissue healing and the achievements of biotechnology have raised hopes that defects of the jaw bones, articular cartilage, or oral mucosa can be repaired without the transfer of autogenous tissue and that custom made body parts can be cultivated from the patients own cells in the lab as a substitute for autogenous grafts.

Cryopreserved Platelet-Rich plasma enhancing calvarial bone defect repair in rabbits: An observation of outcome

Article

Jan 2014

Objective To observe the outcome of cryopreserved platelet-rich plasma(PRP) in repairing rabbit calvarial bone defect. Methods Totally 15 male New Zealand rabbits, weighing 2. 5 kg, were used in this study. Three defect holes were made along the calvarial midline in each rabbit; the upper defect holes were repaired with hydroxyapatite/tricalcium phosphate (HAP/TCP) compounded —80°C cryopreserved PRP gel (experimental hole), the middle defect hole with HAP/ TCP compounded physiological saline (blank hole), and the lower defect hole with HAP/TCP compounded fresh PRP gel (control hole). Five rabbits were sacrificed at 4, 8, and 12 weeks after operation, respectively. Gross observation, X-ray examination, histological observation, and CT scan were performed for the harvested samples, so as to observe whether —80°C cryopreserved PRP gel could promote the defect repair. Results It was found that the osteogenesis of the defects in the experimental holes and the control holes were better than that in the blank holes at 4 weeks and 8 weeks after operation, with the CT values in the experimental hole, control hole and blank hole being (376. 8 it 50. 41), (414 ±71. 41), and (94. 42 ± 37. 02) at 4 weeks after operation and (750. 46±91. 26), (682. 22±111. 53), and (444. 04±47. 12) at 8 weeks after operation, respectively, showing significant differences(P<0. 01); but there was no significant difference between the experimental holes and the control holes at both 4 weeks and 8 weeks after operation(P>0. 05). At 12 weeks after operation, no differences in the osteogenesis of the defects were noticed between the three holes (P>0. 05). Conclusion Cryopreserved PRP is confirmed to have the same effect as fresh PRP in enhancing early repair of calvarial bone defects. © 2015, Second Military Medical University Press. All rights reserved.

Platelet preparations in dentistry: How? Why? Where? When?

Article

May 2015

Luigi Fabrizio Rodella

Cell compatibility of calcium phosphate cement incorporated with platelet concentrate

Article

Jan 2014

We have recently demonstrated the slow release of growth factors from calcium phosphate cements (CPCs) incorporated with platelet concentrate (PC). In the present study, the cell compatibility of CPCs was evaluated by culturing human osteoblast-like cells Saos-2 (ATCC HTB85) to demonstrate the PC effect. CPCs were characterized using scanning electron microscopy (SEM), X-Ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS) and their mechanical properties were tested. The physical and chemical properties of CPCs were little affected by the PC incorporation within the experimented range. The cell proliferation, morphology and migration, measurement of alkaline phosphatase (ALP) levels, mRNA expression for osteopontin (OPG), osteocalcin (OC), glyceraldehyde phosphate dehydrogenase (GAPDH) were evaluated. Higher cell proliferation was performed but the cell migration was not affected by the addition of PC. Actin filaments, focal adhesion, and localized integrin were clearly visible. The PC addition increased ALP activity and expression of GAPDH, OC, and OPG mRNA.

Production and Characterization of Calcium Phosphate Cement Incorporated with Platelet Concentrate

Article

Feb 2014

Calcium phosphate cements (CPCs) incorporated with platelet concentrate (PC) were prepared and characterized in an attempt to improve their bone regenerating performance. The characteristics of CPCs, such as paste injectability, initial setting time, and mechanical strength, were assessed. The generation of hydroxyapatite (HA) was observed with X-Ray diffraction (XRD) and scanning electron microscopy (SEM). The release of platelet-derived growth factor-BB (PDGF-BB) and basic fibroblast growth factor (bFGF) was measured using enzyme linked immunosorbent assay (ELISA). The culture of Saos-2 cells was performed to assay the cell compatibility of CPCs. The paste injectability was enhanced but the cement setting was delayed by the incorporation of PC. The diametral tensile and compressive strengths were deteriorated by incorporated PC. The generation of HA was not affected by PC incorporation. The cumulative concentrations of released PDGF-BB and bFGF increased constantly for about 9 days. The release of PDGF-BB and bFGF linearly increased with the amount of PC added in CPC. According to 12 hr culture, the adhered Saos-2 cells increased with the amount of incorporated PC.

Alveolar Ridge and Sinus Augmentation Utilizing Platelet-Rich Plasma in Combination With Freeze-Dried Bone Allograft: Case Series

Article

Full-text available

Nov 2000

Alveolar bone regeneration is frequently necessary prior to placement of implants. Efforts to improve wound healing have focused on factors that may enhance bone formation following guided bone regeneration (GBR) techniques alone or in combination with bone replacement graft materials. Recent reports suggest that platelet-rich plasma (PRP), presumably high in levels of peptide growth factors, may enhance the formation of new bone when used in combination with autogenous graft material. In this report, the clinical and radiographic results are presented on 15 consecutively treated patients using autologous PRP in combination with freeze-dried bone allograft (FDBA) for sinus elevation and/or ridge augmentation. FDBA and PRP (0.5 g/2cc PRP) were mixed and placed as a composite graft material. A gel formed by mixing autologous thrombin-rich plasma with PRP (1:4 ratio) was used to cover the graft material. Core biopsies of grafted areas were obtained in several patients as part of implant site preparation and were evaluated histologically to determine site maturation. Of 36 implant fixtures, 32 (89%) were considered clinically successful demonstrating complete bone coverage of the implant, no mobility, and a normal radiographic appearance at the time of re-entry and 12 months post-implant exposure. Four implants were removed due to mobility at the time of surgical exposure. Histologic evaluation of biopsy specimens revealed numerous areas of osteoid and bone formation around FDBA particles, with no evidence of inflammatory cell infiltrate. These clinical and histological findings suggest that ridge augmentation and sinus grafting with FDBA in combination with PRP provide a viable therapeutic alternative for implant placements. Future studies are necessary to determine whether PRP enhances new bone formation or maturation with bone replacement allografts.

Plasma-Rich Growth Factors

Article

Jan 2001

Effect of platelet-rich plasma on bone regeneration in autogenous bone graft

Article

Jan 2004

In this study, we evaluated the effect of platelet-rich plasma (PRP) on bone regeneration in an autogenous bone graft in a canine model. The mandibular premolar teeth had been bilaterally extracted previously, and the ridges had been allowed to heal for 3 months. After this period, continuity resection was performed on both sides of the mandible. One defect (the PRP group) was reconstructed with the original particulate bone mixed with PRP. As a control, the contralateral defect (non-PRP group) was reconstructed with the original particulate bone alone. Biopsies after 6 weeks showed lower levels of bone formation in the PRP group than in the non-PRP group, and fluorescence microscopy revealed a delay in the remodelling of grafts loaded with PRP. These findings suggest that the addition of PRP does not appear to enhance new bone formation in autogenous bone grafts.

Platelet-Rich Plasma: Evidence to Support Its Use

Article

Apr 2004
J ORAL MAXIL SURG

Robert E Marx

Platelet-rich plasma

Article

Jun 1998
ORAL SURG ORAL MED O

Platelet-rich plasma is an autologous source of platelet-derived growth factor and transforming growth factor beta that is obtained by sequestering and concentrating platelets by gradient density centrifugation. This technique produced a concentration of human platelets of 338% and identified platelet-derived growth factor and transforming growth factor beta within them. Monoclonal antibody assessment of cancellous cellular marrow grafts demonstrated cells that were capable of responding to the growth factors by bearing cell membrane receptors. The additional amounts of these growth factors obtained by adding platelet-rich plasma to grafts evidenced a radiographic maturation rate 1.62 to 2.16 times that of grafts without platelet-rich plasma. As assessed by histomorphometry, there was also a greater bone density in grafts in which platelet-rich plasma was added (74.0% ± 11%) than in grafts in which platelet-rich plasma was not added (55.1% ± 8%; p = 0.005).

Effects of platelet-rich plasma on bone healing in combination with autogenous bone and bone substitutes in critical-size defects: An animal experiment

Article

Apr 2004
CLIN ORAL IMPLAN RES

Objectives: An animal study was carried out to investigate the influence of platelet‐rich plasma (PRP) on the regeneration of bony defects. Material and methods: Critical‐size defects in the forehead region of a mini‐pig were filled with randomly distributed combinations of autogenous bone, tricalcium‐phosphate granules (CeraSorb™), bovine spongious blocks (BioOss™) and a bovine bone inducing collagenous sponge (Colloss™) with and without PRP in two preparations (Cusasan, 3i). The animals were killed after 2, 4 and 12 weeks. The specimens were evaluated microradiographically and immunohistologically. Results: Autologous bone (38±9.9%) and Colloss (52.6±4.0%) showed the highest remineralization rates at 2 weeks. The initial high expression of BMP‐2 in the Colloss®‐group gives evidence of an early initiation of bony regeneration. At 2 weeks PRP ad modum 3i was able to enhance bone healing significantly ( P =0.028) only when applied in combination with autogenous bone (62.8±1.6%). Four weeks after surgery, both PRP preparations did no longer increase bony regeneration in the autogenous groups. The osteoconductive effect of Bio‐Oss™ (38.7±5.5%) and CeraSorb™ (41±4.9%) was remarkable as well 4 weeks after surgery. Nevertheless, the addition of PRP hardly influenced bony regeneration, ceramic degradation or cytokine expression when bone substitutes were applied. At 12 weeks, the level of reossification had adjusted similarly in all groups. Conclusion: PRP did not add additional benefit when xenogenic bone substitutes were used. However, a significant effect on bone regeneration was found in the autogenous group initially when PRP is added.

Platelet-rich plasma: Growth factor enhancement for bone grafts

Article

Jul 1998
ORAL SURG ORAL MED O

Platelet-rich plasma is an autologous source of platelet-derived growth factor and transforming growth factor beta that is obtained by sequestering and concentrating platelets by gradient density centrifugation. This technique produced a concentration of human platelets of 338% and identified platelet-derived growth factor and transforming growth factor beta within them. Monoclonal antibody assessment of cancellous cellular marrow grafts demonstrated cells that were capable of responding to the growth factors by bearing cell membrane receptors. The additional amounts of these growth factors obtained by adding platelet-rich plasma to grafts evidenced a radiographic maturation rate 1.62 to 2.16 times that of grafts without platelet-rich plasma. As assessed by histomorphometry, there was also a greater bone density in grafts in which platelet-rich plasma was added (74.0% +/- 11%) than in grafts in which platelet-rich plasma was not added (55.1% +/- 8%; p = 0.005).

Plasma Rich in Growth Factors: Preliminary Results of Use in the Preparation of Future Sites for Implants

Article

Jul 1999

E Anitua

This article presents preliminary clinical evidence of the beneficial effect of the use of plasma rich in growth factors of autologous origin. The plasma is obtained from the individual patient by plasmapheresis. The macroscopic and microscopic results obtained with bone regeneration using this technique, which uses no membrane or barrier, can be observed. The incorporation of these concepts can introduce several advantages, including the enhancement and acceleration of bone regeneration and more rapid and predictable soft tissue healing.

Sinus grafting using platelet-rich plasma – Initial case presentation

Article

Nov 2000

Recent research has indicated that an element of the proteins contained in platelet-rich plasma can be utilized to increase the speed of bone deposition and quality of bone regeneration when augmenting edentulous sites for implant placement. The growth factors present in platelet-rich plasma are believed to initiate a sequence of microscopic events that ultimately result in the formation of osseous tissue capable of supporting implants for subsequent prosthetic restoration. This article demonstrates a surgical protocol used to harvest platelet-rich plasma and the manner in which it can be implemented in a clinical procedure for the restoration of partially edentulous patients.

Localized Ridge Augmentation Using GBR and Platelet-Rich Plasma: Case Reports

Article

Sep 2001

Combining platelet-rich plasma (PRP) with autogenous bone graft materials has recently been advocated as a means of enhancing rate and quality of new bone formation in regenerative procedures. The aim of this case series was to evaluate the potential of PRP in combination with bone allograft to enhance bone regeneration in alveolar ridge defects exhibiting both vertical and horizontal loss prior to the placement of dental implants. Augmentation resulted in clinical and radiographic gains in both vertical and horizontal components of the osseous defects, thereby facilitating subsequent placement of dental implants. Histologic evaluation of the cases revealed the presence of residual allograft particles surrounded by connective tissue as well as newly formed bone within the grafted areas. However, the addition of PRP did not appear to enhance the quality or quantity of new bone formation over that reported in comparable guided bone regeneration (GBR) studies without PRP.

The use of plasma-rich growth factors (PRGF) in oral surgery

Article

Sep 2001

E Anitua

The therapeutic objective of utilizing growth factors in oral surgery is to improve upon the body's regenerative capacity. In many situations, the unaided regeneration process is insufficient to allow complete repair of both bone and soft tissues. This article presents two clinical cases that describe different applications of growth-factor preparation applied at the surgical site in order to stimulate regeneration of osseous and epithelial tissues. Both clinical cases demonstrate the therapeutic effectiveness of utilizing the described technique for the incorporation of plasma-rich growth factors as an adjuvant in regenerative procedure.

Use of Particulate Dentin-Plaster of Paris Combination with/without Platelet-Rich Plasma in the Treatment of Bone Defects Around Implants

Article

Jan 2002

To evaluate the effect of particulate dentin-plaster of Paris with and without platelet-rich plasma (PRP) on bone healing and new bone formation around titanium dental implants in a canine model. Histologic sections and histomorphometric analysis of the defects were obtained at 6 and 12 weeks after surgery. Three circular bone defects were surgically prepared in iliac crest sites in each of 10 animals. A total of 30 Avana dental implants were placed in the animals. They were self-tapping, screw-type implants, 10 mm in length and 4 mm in diameter, all made of commercially pure titanium. A titanium implant was placed centrally in each defect. In each dog, the defects were treated with 1 of the following 3 treatment modalities: (1) no treatment (control); (2) grafting with particulate dentin-plaster of Paris; (3) grafting with particulate dentin-plaster of Paris and PRP. Histologic analysis showed that all of the bone defects surrounding the implants that were treated with particulate dentin-plaster of Paris, with and without PRP, were filled with new bone. The defects that were not treated (control) demonstrated new bone formation only in the inferior threaded portion of the implants. Histomorphometric results revealed a higher percentage of bone contact with particulate dentin-plaster of Paris and PRP compared to the control and particulate dentin-plaster of Paris. These results suggested that bone defects around titanium implants can be treated successfully with particulate dentin-plaster of Paris, and that the outcome can be improved if PRP is also used.

Osteogenesis distraction and platelet-rich plasma for bone restoration of the severely atrophic mandible: Preliminary results

Article

Jul 2002
J ORAL MAXIL SURG

The purpose of this study was to evaluate a new method of restoring severe atrophic mandible using platelet-rich plasma (PRP) during distraction osteogenesis. Since 1999, 2 men and 3 women with severe atrophy (Cawood and Howell classes V and VI) of a completely edentulous mandible have been treated with a novel distraction procedure. During the surgery, a mixture of autologous bone graft, harvested from the iliac crest, and an autologous platelet concentrate, obtained from platelet-rich plasma, filled the distraction gap. This mixture constituted an autologous bone-platelet gel that was used to create a useful bony scaffold for distraction regenerate. After a latency period of 15 days, a distraction run of 0.5 mm/d, and a 60-day period of consolidation, the distraction device was removed and implants were placed simultaneously. In all treated patients, planned distraction height was achieved with a considerable enhancement of bony regeneration, and in all cases it was possible to place implants at a planned time. The combination of these recent and innovative regenerative methods seems to be effective in restoring the severe atrophic mandible.

Investigation of platelet-rich plasma in rabbit cranial defects: A pilot study

Article

Nov 2002
J ORAL MAXIL SURG

The purpose was to evaluate the effect of platelet-rich plasma (PRP) on bone healing. Fifteen rabbits were included in this randomized, blinded, prospective pilot study. Four equal 8 mm diameter cranial bone defects were created and immediately grafted with autogenous bone, PRP alone, autogenous bone and PRP, and no treatment as a control. The defects were evaluated by digital subtraction radiography with step-wedge calibration, histology, and histomorphometric analysis performed at 1, 2, and 4 months. The results showed a significant increase in histomorphometric bone area and radiographic bone density in both bone and bone and PRP samples as compared with the control and PRP alone. No significant increase in bone formation was seen with the addition of PRP to autogenous bone. No significant difference in bone formation was seen between defects treated with PRP alone and control sites. No significant improvement, radiographically or histomorphometrically, was seen with the addition of PRP in bone formation in noncritical sized defects in the rabbit cranial model. However, bone and bone and PRP showed a histomorphometric tendency toward increased bone formation at 1, 2, and 4 months.

Human recombinant tissue factor, platelet-rich plasma, and tetracycline induce a high-quality human bone graft: A 5-year survey

Article

May 2003

To increase human bone graft regeneration and quality by the use of a mixture containing autologous ground calvarial bone, human recombinant tissue factor (rhTF), platelet-rich plasma (PRP), and tetracycline. Maxillary sinus floor augmentation was performed on 18 patients by grafting a "bone paste" made of PRP (1.8 x 10(6) platelets/mm3 plasma), about 1 microg rhTF, calvarial bone chips (2 to 5 mm in size), and tetracycline (10 to 30 microg/mL preparation). Five to 6 months after the surgical phase and grafting a bone core was extracted for implant fixation, and the osseous core samples were analyzed microscopically. Histology revealed vascularized connective tissue rich in lamellar bone spicules containing osteocytes and surrounded by osteoblasts. The success rate of grafting was 90.3%. In 6-month postoperative blood samples, no residual coagulating disturbances could be found. The combination of calvarial bone chips, rhTF, PRP, and tetracycline results in a paste that is easy to handle, safe for patients, and possesses high bone-regeneration capacity. The generalized use in implant dentistry, oral surgery, and orthopedics of such a protocol could facilitate the healing process as well as patient safety and surgeon comfort.

Molecular mechanisms underlying osteoclast formation and activation

Article

Jul 2003
EXP GERONTOL

Bruce R. Troen

Osteoporosis is one of the leading causes of morbidity in the elderly and is characterized by a progressive loss of total bone mass and bone density. Bone loss in osteoporosis is due to the persistent excess of osteoclastic bone resorption over osteoblastic bone formation. Receptor activator of NFkappaB ligand (RANKL) critically regulates both osteoclast differentiation and activation. TRAFs appear to be central coupling molecules in the signal transduction pathways that regulate osteoclastogenesis, cathepsin K is the major mediator of osteoclastic bone resorption, and sex steroids and aging also affect osteoclastogenesis and osteoclast activity. However, bone homeostasis depends upon the intimate coupling of bone formation and bone resorption, wherein both osteoclasts and osteoblasts exert vital stimulatory and inhibitory effects upon each other via molecules such as RANKL, TGFbeta, PDGF, BMP2, and Mim-1. This review will highlight some of the major features of the complex circuit of cytokines, growth factors, and hormones that underlies the formation and function of osteoclasts and the dynamic equilibrium that marks the interaction between osteoclasts and osteoblasts.

Influence of PRP on autogenous sinus grafts

Article

Nov 2003

Since platelet -rich plasma (PRP) has been introduced to the field of oral surgery, it has become a widely accepted additive for bone regeneration treatment. The aim of this study was to evaluate the regenerative capacity of PRP in a sinus graft study on sheep. Twelve adult sheep underwent a bilateral sinus floor elevation procedure with cancellous bone from the iliac crest. Unilaterally, PRP was administrated to the bone graft. After 4 (six sheep) and 12 weeks (six sheep), bone biopsies were obtained from each site. With histomorphometric analysis we evaluated both the percentage of newly formed bone within the grafted site and the percentage of the contact area between the grafted bone and the newly formed bone. After 4 weeks the mean proportion of newly formed bone on the control side was 26.1%, whereas it was 29.2% on the test side. After 12 weeks it was 46.9% on the control side and 51.1% on the test side. The area of contact between the graft and the newly formed bone was 73.0% on the control side and 78.5% on the test side after 4 weeks, and 87.2% on the control side and 90.1% on the test side after 12 weeks. A statistical analysis did not reveal significant differences between the control and the test side. The results of the present experimental study show a regenerative capacity of PRP of quite low potency. Further basic research is needed to investigate more profoundly the possibilities of PRP in bone regeneration.

Effect of platelet-rich plasma on bone regeneration in autogenous bone graft

Article

Feb 2004

Mandibular reconstruction: A histological and histomorphometric study on the use of autogenous scaffolds, particulate cortico-cancellous bone grafts and platelet rich plasma in goats

Article

Feb 2004

Twenty-eight goats underwent a continuity resection of the mandibular angle. In all goats primary reconstruction was carried out using specially designed pre-shaped osteosynthesis plates and monocortical screws. The original cortical scaffold was used to bridge the defect, filled with an autogenous particulate bone graft in 14 goats, whereas platelet-rich-plasma (PRP) was added in another 14 goats. Both groups were divided in three subgroups that were sacrificed after 3, 6 and 12 weeks. Histological and histomorphometric evaluation revealed that the use of PRP enhanced the bone healing considerably. This effect was statistically significant and particularly visible in the 6 and 12 weeks' groups

Bone formation in the presence of platelet-rich plasma vs. bone morphogenetic protein-7

Article

Feb 2004
BONE

Growth factors contained in platelet-rich plasma (PRP) have recently been proposed to enhance maturation of bone grafts and, in combination with anorganic bovine bone, to support repair in the treatment of small bone defects in maxillofacial surgery. Bone morphogenetic proteins (BMP) carried in a matrix may be able to replace the autologous bone graft in the treatment of critical size defects. However, no studies have compared the bone stimulating capacity of PRP and BMP. Likewise there is no data comparing the effects of PRP in either an autologous bone graft or in anorganic bovine bone. We augmented the mandible of Wistar rats (n = 28) on both sides with either anorganic bovine bone (Bio-Oss) or autologous rib bone. On the test side we applied either 20 microl of autologous PRP or 10 microl of rhBMP-7 (4 groups, n = 7). In addition, bone induction was evaluated in an extraskeletal site (n = 14). A polychrome sequential labeling was performed. The animals were sacrificed by intra-vital perfusion on day 50. Undecalcified ground sections were evaluated by microradiography, digitized histomorphometry and under fluorescent light. The qualitative analysis of fluorochrome labels suggested that PRP and rhBMP-7 accelerated bone growth. However, histomorphometric analysis revealed no significant differences in the area of newly mineralized bone under either the influence of PRP or rhBMP-7 on autologous bone graft. Likewise, the addition of PRP to anorganic bovine bone showed no statistical difference to the control group. The strongest bone stimulating effect was seen for the combination of rhBMP-7 with anorganic bovine bone (p = 0.028). In the extraskeletal model, newly formed bone was evident in the presence of rhBMP-7, but not of PRP. In conclusion, according to the histomorphometry, the addition of platelet-rich plasma failed to enhance bone formation on anorganic bovine bone and on autologous bone grafts.

Transforming growth factor-® induces osteoclast formation in the absence of RANKL

Article

Feb 2004
BONE

Transforming growth factor beta (TGFbeta) is a multifunctional growth factor that is produced by many cells in bone and is abundant in the bone matrix. TGFbeta is known to regulate RANKL-induced osteoclast formation and bone resorbing activity. In this study we sought to determine whether TGFbeta could directly induce osteoclast formation by a RANKL-independent mechanism. We found that the addition of TGFbeta to cultures of human monocytes and RAW 264.7 cells (in the presence of M-CSF and the absence of RANKL, TNFalpha or IL-6/IL-11) was sufficient to induce the formation of TRAP+ and VNR+ cells, which formed actin rings and were capable of extensive lacunar resorption. The addition of osteoprotegerin or antibodies to TNFalpha and its receptors, as well as antibodies to gp130, did not inhibit lacunar resorption, indicating that TGFbeta did not act by stimulating RANKL, TNF or IL-6 production by monocytes. TGFbeta-induced osteoclast formation was qualitatively different from that induced by RANKL with numerous TRAP+/VNR+ mononuclear and small multinucleated cells being formed; these cells produced many small resorption lacunae. Our results indicate that TGFbeta, which is abundant in the bone matrix, can, in the presence of M-CSF, directly induce mononuclear phagocyte osteoclast precursors to differentiate into osteoclastic cells capable of lacunar resorption.

Platelet-Rich Plasma: Ready or Not?

Article

May 2004
J ORAL MAXIL SURG

Platelet rich plasma and fresh frozen bone allograft as enhancement of implant fixation. An experimental study in dogs

Article

Jun 2004

Platelet rich plasma (PRP) is an autologous source of growth factors. By application of PRP around cementless implants alone or in combination with bone allograft chips, early implant fixation and gap healing could be improved. We inserted two porous HA coated titanium implants extraarticularly in each proximal humerus of eight dogs. Each implant was surrounded by a 2.5 mm gap. Four treatments were block randomized to the four gaps in each dog: Treatment 1: empty gap, treatment 2: PRP, treatment 3: fresh frozen bone allograft, treatment 4: fresh frozen bone allograft + PRP. PRP was prepared from each dog prior to operation by isolating the buffycoat from centrifuged blood samples. Platelet count in PRP was increased 670% compared to baseline level. Calcium/thrombin was added to degranulate platelets and form a gel. Three weeks after surgery, push‐out test and histomorphometri was performed. After three weeks, the non‐allografted implants had poor mechanical properties. Bone grafting significantly increased implant fixation, bone formation in the gap and bone growth on the implant surface. We found no significant effect of PRP alone or mixed with bone allograft on implant fixation or bone formation. In conclusion, we showed the importance of bone allografting on early implant fixation and bone incorporation but we found no effect of PRP. More studies are needed to investigate the effect and possible clinical applications of platelet concentrates which are now being commercialised. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.

Efficacy of Platelet-Rich Plasma in Alveolar Bone Grafting

Article

Jun 2004
J ORAL MAXIL SURG

In this study, we performed alveolar bone grafting with autologous iliac cancellous bone incorporation with platelet-rich plasma (PRP) and evaluated its efficacy in osteoregeneration. Seven alveolar cleft patients with adult dentition (average age, 16.1 years) underwent iliac bone grafting with PRP. Quantitative evaluation of regenerated bone was made with 3-dimensional computed tomography scans and compared with controls. The average of the volume ratio of regenerated bone to alveolar cleft in cases with PRP was higher than in controls (P <.05). There were no complications from the blood draw or PRP. PRP was a safe and cost-effective source for growth factors and was easy to extract. It could enhance the osteogenesis of alveolar bone grafting in cleft lip and palate patients and may useful for subsequent orthodontic therapy.

Is Platelet-rich Plasma the Perfect Enhancement Factor? A Current Review

Article

Jan 2003

Guided bone regeneration is an accepted surgical method employed in implant dentistry to increase the quantity and quality of the host bone in areas of localized alveolar defects. The lack of predictability in osseous regenerative procedures with various grafting materials suggests that improvement in the osteoinductive properties of these materials is highly desirable. Platelet-rich plasma (PRP), a modification of fibrin glue made from autologous blood, is being used to deliver growth factors in high concentration to sites requiring osseous grafting. Growth factors released from the platelets include platelet-derived growth factor, transforming growth factor beta, platelet-derived epidermal growth factor, platelet-derived angiogenesis factor, insulin-like growth factor 1, and platelet factor 4. These factors signal the local mesenchymal and epithelial cells to migrate, divide, and increase collagen and matrix synthesis. PRP has been suggested for use to increase the rate of bone deposition and quality of bone regeneration when augmenting sites prior to or in conjunction with dental implant placement Only 6 human studies using PRP have been found in the dental implant literature and 5 were case series or reports. Thus, there is clearly a lack of scientific evidence to support the use of PRP in combination with bone grafts during augmentation procedures. This novel and potentially promising technique requires well-designed, controlled studies to provide evidence of efficacy.

Evaluation of Platelet-Rich Plasma in Combination with Anorganic Bovine Bone in the Rabbit Cranium: A Pilot Study

Article

Nov 2003

Platelet-rich plasma (PRP) is potentially useful as an adjunct to allograft and xenograft materials in oral and maxillofacial bone and implant reconstructive surgery. This study compares bone healing and formation in 4 cranial defects in rabbits grafted with autogenous bone, xenograft, and xenograft with PRP (with a no-graft group as a control). Fifteen New Zealand white rabbits were included in this randomized, blind, prospective pilot study. Four identical 8-mm-diameter defects were created in each rabbit cranium and immediately grafted with the above materials. Five rabbits were evaluated at 1 month, 5 at 2 months, and 5 at 4 months. Radiographs were used to evaluate bone density. Radiographically, sites at which Bio-Oss, autogenous bone, and Bio-Oss + PRP were grafted showed a significant increase in bone density at 1 month (P = .05 for Bio-Oss, P = .02 for autogenous bone, P = .008 for Bio-Oss + PRP) and at 4 months (P = .02 for Bio-Oss, P = .04 for autogenous bone, P = .05 for Bio-Oss + PRP). Autogenous bone sites (P < .001) and Bio-Oss + PRP sites (P < .001) also showed significant increases at 2 months. Histomorphometrically, autogenous bone sites showed a significantly greater increase than control sites (P = .08 at 1 month, P = .03 at 2 months, P = .01 at 4 months), Bio-Oss sites (P < .001 at all 3 evaluation points), or Bio-Oss + PRP sites (P = .009 at 1 month, P = .02 at 2 months, P = .01 at 4 months). Furthermore, Bio-Oss + PRP sites showed a significantly greater increase in bone area at 1, 2, and 4 months than Bio-Oss alone (P = .003 at 1 month, P = .02 at 2 months, P = .006 at 4 months). Radiographs showed significantly greater bone density at the Bio-Oss, autogenous bone, and Bio-Oss + PRP sites than at control sites at nearly every point in time evaluated; however, clinical significance is difficult to determine, since all materials appeared dense on the radiograph. Histomorphometry showed that the increase in bone area at autogenous sites was significantly greater than that seen with other grafting materials or at the control sites. This study showed a histomorphometric increase in bone formation with the addition of PRP to Bio-Oss in non-critical-sized defects in the rabbit cranium.

Effects of Platelet-Rich Plasma on Bone Healing in Combination With Autogenous Bone and Bone Substitutes in Critical Size Defects

Article

May 2004

An animal study was carried out to investigate the influence of platelet-rich plasma (PRP) on the regeneration of bony defects. Critical-size defects in the forehead region of a mini-pig were filled with randomly distributed combinations of autogenous bone, tricalcium-phosphate granules (CeraSorb), bovine spongious blocks (BioOss) and a bovine bone inducing collagenous sponge (Colloss) with and without PRP in two preparations (Cusasan, 3i). The animals were killed after 2, 4 and 12 weeks. The specimens were evaluated microradiographically and immunohistologically. Autologous bone (38 +/- 9.9%) and Colloss (52.6 +/- 4.0%) showed the highest remineralization rates at 2 weeks. The initial high expression of BMP-2 in the Colloss-group gives evidence of an early initiation of bony regeneration. At 2 weeks PRP ad modum 3i was able to enhance bone healing significantly (P=0.028) only when applied in combination with autogenous bone (62.8 +/- 1.6%). Four weeks after surgery, both PRP preparations did no longer increase bony regeneration in the autogenous groups. The osteoconductive effect of Bio-Oss (38.7 +/- 5.5%) and CeraSorb (41+/-4.9%) was remarkable as well 4 weeks after surgery. Nevertheless, the addition of PRP hardly influenced bony regeneration, ceramic degradation or cytokine expression when bone substitutes were applied. At 12 weeks, the level of reossification had adjusted similarly in all groups. PRP did not add additional benefit when xenogenic bone substitutes were used. However, a significant effect on bone regeneration was found in the autogenous group initially when PRP is added.

Effects of platelet-rich plasma on bone healing in combination with autogenous bone and bone substitutes in critical-size defects. An animal experi-ment Troen BR: Molecular mechanisms underlying osteoclasts for-mation and activation

Jan 2003
605

J Wiltfang
Fr
E Nkenke

Wiltfang J, Kloss FR, Nkenke E, et al: Effects of platelet-rich plasma on bone healing in combination with autogenous bone and bone substitutes in critical-size defects. An animal experi-ment. Clin Oral Implant Res 15:187, 2004 21. Troen BR: Molecular mechanisms underlying osteoclasts for-mation and activation. Exp Gerontol 38:605, 2003

Mandibular reconstruction

Jan 2004
48

Fennis

Human recombinant tissue factor, platelet-rich plasma, and tetracycline induce a high-quality human bone graft

Jan 2003
411

Philippart

Platelet-rich plasma

Jan 2004
489

Marx

Effects of Platelet-Rich Plasma on the Healing of Autologous Bone Grafted Mandibular Defects in Dogs

Abstract

No full-text available

Recommended publications

Cancellous bone grafting with collagen stents