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Effect of low speed drilling on osseointegration using simplified drilling procedures
Abstract
Our aim was to find out whether simplified drilling protocols would provide biological responses comparable to those of conventional drilling protocols at the low rotational speed of 400rpm. Seventy-eight root form endosseous implants with diameters of 3.75, 4.2, and 5mm were placed into canine tibias and allowed to heal for 3 and 5 weeks. After the dogs had been killed, the samples of implanted bone were retrieved and processed for non-decalcified histological sectioning. Bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) analyses were made on the histological sections. Implants treated by the simplified protocol resulted in BIC and BAFO values comparable to those obtained with the conventional drilling protocol, and there were no significant differences in the technique or diameter of the drilling. The results suggest that the simplified procedure gives biological outcomes comparable to those of the conventional procedure.
Copyright © 2015 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
... The drilling speed was set to 400 rpm for all drills under abundant sterile saline irrigation. 11 Each animal received two implants in each proximal tibia. The left and right limbs received 3.75-and 4.2-mm-diameter implants utilizing the conventional and simplified drilling sequences, respectively. ...
... 2,4,10 In fact, a recent study demonstrated that simplified and conventional protocols reached no statistically significant difference on osseointegration parameters. 11 From a surgical perspective, the total surgical time of the simplified protocol from incision to closure would be significantly shortened and lead to fewer postsurgical complications. 12 However, this reduction in the number of drills used to reach the preparation final diameter will also have the drawback of reducing the number of attempts to correct location or angulation of definitive implant placement. ...
... Regarding the utilized drilling protocol, previous studies have investigated the effect of using a simplified drilling technique as a replacement for the conventional osteotomy preparation, reporting minimal differences in bone response between protocols. 2,4,10,11 In contrast to the aforementioned studies, where osteotomies were performed in a higher-speed protocol with irrigation, the present study combined a low-speed technique with irrigation. Histomorphology showed that despite the drilling protocol, no signs of osteonecrosis or excessive inflammatory response were observed along with woven bone formation. ...
... Gaspar et al. compared drilling at low speed (50 rpm) without irrigation versus high-speed drilling (800 rpm) with irrigation in rabbit tibias and concluded that the effects of lowspeed drilling (50 rpm) without irrigation and conventional drilling (800 rpm) under abundant irrigation preserved the bone cell viability [18]. Sarendranath et al. studied the effects of slow drilling speed (drilling at 400 rpm) on osseointegration after simplified drilling protocols and reported that the bone-to-implant contact and bone area fraction occupancy were comparable to those obtained by conventional drilling protocols [19]. ...
... Although drilling at slow speeds has some benefits, such as obtaining of vital bone for autografts, possibility of correction of the drill direction, and control of the temperature [16][17][18] and similar bone formation during healing compared to conventional drilling speeds [19][20][21][22], there is a lack of agreement about the drilling speed range that might be used during slow bone drilling with different drill designs when a single-bur protocol for the implant bed preparation is used. ...
... The time required to finish the implant bed when drilling at 300 rpm was shorter (30 ± 3 s) compared to drilling at 50 rpm. (a) Drill 1, (b) Drill 2, and (c) Drill 3. B base temperature, ΔT differential temperature T Max − T base , T Max maximum temperature recorded when the drill reached the drilling depth This is in agreement with previous studies which found that slow drilling speeds of different values, such as 50 [16,18], 317 [27], 400 [19], 100 and 500 [22], and 230 to 570 rpm [1], resulted in minimal variations of the temperature. ...
Aims:
To evaluate the real-time bone temperature changes during the preparation of the implant bed with a single-drill protocol with different drill designs and different slow drilling speeds in artificial type IV bone.
Materials and methods:
For this experimental in vitro study, 600 implant bed preparations were performed in 10 bovine bone disks using three test slow drilling speeds (50/150/300 rpm) and a control drilling speed (1200 rpm). The temperature at crestal and apical areas and time variations produced during drilling with three different drill designs with similar diameter and length but different geometry were recorded with real-life thermographic analysis. Statistical analysis was performed by two-way analysis of variance. Multiple comparisons of temperatures and time with the different drill designs and speeds were performed with the Tukey's test.
Results:
T Max values for the control drilling speed with all the drill designs (D1 + 1200; D2 + 1200; D3 + 1200) were higher compared to those for the controls for 11 ± 1.32 °C (p < 0.05). The comparison of T Max within the test groups showed that drilling at 50 rpm resulted in the lowest temperature increment (22.11 ± 0.8 °C) compared to the other slow drilling speeds of 150 (24.752 ± 1.1 °C) and 300 rpm (25.977 ± 1.2 °C) (p < 0.042). Temperature behavior at crestal and apical areas was similar being lower for slow drilling speeds compared to that for the control drilling speed. Slow drilling speeds required significantly more time to finish the preparation of the implant bed shown as follows: 50 rpm > 150 rpm > 300 rpm > control (p < 0.05).
Conclusions:
A single-drill protocol with slow drilling speeds (50, 150, and 300 rpm) without irrigation in type IV bone increases the temperature at the coronal and apical levels but is below the critical threshold of 47 °C. The drill design in single-drill protocols using slow speeds (50, 150, and 300 rpm) does not have an influence on the thermal variations. The time to accomplish the implant bed preparation with a single-drill protocol in type IV bone is influenced by the drilling speed and not by the drill design. As the speed decreases, then more time is required.
... The drilling speed was set to 400 rpm for all drills under abundant sterile saline irrigation. 11 Each animal received two implants in each proximal tibia. The left and right limbs received 3.75-and 4.2-mm-diameter implants utilizing the conventional and simplified drilling sequences, respectively. ...
... 2,4,10 In fact, a recent study demonstrated that simplified and conventional protocols reached no statistically significant difference on osseointegration parameters. 11 From a surgical perspective, the total surgical time of the simplified protocol from incision to closure would be significantly shortened and lead to fewer postsurgical complications. 12 However, this reduction in the number of drills used to reach the preparation final diameter will also have the drawback of reducing the number of attempts to correct location or angulation of definitive implant placement. ...
... Regarding the utilized drilling protocol, previous studies have investigated the effect of using a simplified drilling technique as a replacement for the conventional osteotomy preparation, reporting minimal differences in bone response between protocols. 2,4,10,11 In contrast to the aforementioned studies, where osteotomies were performed in a higher-speed protocol with irrigation, the present study combined a low-speed technique with irrigation. Histomorphology showed that despite the drilling protocol, no signs of osteonecrosis or excessive inflammatory response were observed along with woven bone formation. ...
Purpose:
This study evaluated whether simplified drilling protocols would provide comparable histologic and histomorphometric results to conventional drilling protocols at a low rotational speed.
Materials and methods:
A total of 48 alumina-blasted and acid-etched Ti-6Al-4V implants with two diameters (3.75 and 4.2 mm, n = 24 per group) were bilaterally placed in the tibiae of 12 dogs, under a low-speed protocol (400 rpm). Within the same diameter group, half of the implants were inserted after a simplified drilling procedure (pilot drill + final diameter drill), and the other half were placed using the conventional drilling procedure. After 3 and 5 weeks, the animals were euthanized, and the retrieved bone-implant samples were subjected to nondecalcified histologic sectioning. Histomorphology, bone-to-implant contact (BIC), and bone area fraction occupancy (BAFO) analysis were performed.
Results:
Histology showed that new bone was formed around implants, and inflammation or bone resorption was not evident for both groups. Histomorphometrically, when all independent variables were collapsed over drilling technique, no differences were detected for BIC and BAFO; when drilling technique was analyzed as a function of time, the conventional groups reached statistically higher BIC and BAFO at 3 weeks, but comparable values between techniques were observed at 5 weeks; 4.2-mm implants obtained statistically higher BAFO relative to 3.75-mm implants.
Conclusion:
Based on the present methodology, the conventional technique improved bone formation at 3 weeks, and narrower implants were associated with less bone formation.
... Success of osseointegration depends on avoidance of heat generation 12 41 . Bone was assessed after 3 and 5 weeks and showed similar osseointegration with both protocols 41 . ...
... Success of osseointegration depends on avoidance of heat generation 12 41 . Bone was assessed after 3 and 5 weeks and showed similar osseointegration with both protocols 41 . ...
Background: Drilling speed during osteotomy in implant site preparation is an important factor that affects heat
generation, cell vitality and primary stability and consequently Osseointegration of the implant. A thorough understanding
of this impact is important for taking suitable precautions for successful dental rehabilitation. Aim: The objective of this
study is to review the available literature regarding the impact of drilling speed on heat generation and other related
parameters that influence the success of dental implants. Material and Methods: Suitable research papers relevant for
study were identified through electronic database of available dental literature in PubMed and MEDLINE for all articles
published till February, 2021. Peer-reviewed dental and PubMed indexed journals were selected. Search was done using
certain relevant key words and terms. Results: The initial search revealed a total of 281 articles which were then screened
and a total of 61 articles were selected based on the inclusion criteria. Focus was laid on the studies related to drilling
speed and its impact on osseointegration, heat generation during osteotomy, drilling speed and bone viability, drilling
speed and primary stability of implant and particle size of the bone collected. Heat generation during implant placement
is affected by multiple factors with drilling speed being one of them. Conclusion: Researchers have reached contradictory
conclusions regarding the impact of drilling speed on heat generation during osteotomy and other parameters. However,
studies in the recent past are favoring low speed drilling owing to the advantage of perfect control of the drilling depth and
the possibility of collection of a considerable amount of viable granular bone grafts during the procedure.
... Leaving dead, carbonated or calcified tissues can affect the induction of osteogenesis or immune response. This leads to the intensification of bone resorption, which directly translates into the ability of the implant to connect to the bone [21,22]. Different drill geometries have an impact on the nature of the borehole, including the amount of debris remaining in the drilled hole and the degree of soft tissue damage. ...
... Initial mechanical engagement in the healing phase is important for the remodeling process [33][34][35][36]. The osseointegration process results in achieving secondary stability, which is a direct contact between the intact bone and implant surface [21,22,37]. ...
The purpose of this study was to present the level of bone tissue deformation after drilling under variable conditions in three different dental implant systems in a microscopic analysis. Straumann, Osstem, and S-Wide systems were used to drill boreholes in 27 porcine ribs at three different rotation speeds and under three different cooling conditions. The material was analyzed using a Nikon 80i microscope. The analysis concerned the morphological quality of the obtained boreholes. The statistical analysis revealed that satisfactory results in all drilling systems were obtained when the rotational speed did not exceed 800 revolutions per minute (rpm) regardless of the cooling temperature. However, increased rotational speed and cooling at 4 °C produced better results than without cooling in all the tested systems. Different implant systems have unique drill geometry and therefore generate differences in tissue damage under various conditions. In the experiment, a sufficient required structure was obtained in all systems, but the Straumann system yielded the best results under all the examined conditions.
... For example, a series of previous studies have shown that the simplified version (pilot drill immediately followed by the final diameter drill for implants of 3.75, 4.2, and 5 mm) of the traditional gradual drilling expansion results in comparable osseointegration relative to classic protocols. [32][33][34][35][36][37] Recent work has confirmed no statistical difference on osseointegration parameters between simplified and conventional protocols. 32 Alternative to reducing the number of drills, alteration in drill design to include progressive diameter achievement through the employment of a single progressive drill has been demonstrated to not decrease early osseointegration. ...
... [32][33][34][35][36][37] Recent work has confirmed no statistical difference on osseointegration parameters between simplified and conventional protocols. 32 Alternative to reducing the number of drills, alteration in drill design to include progressive diameter achievement through the employment of a single progressive drill has been demonstrated to not decrease early osseointegration. 38 From a surgical perspective, the total surgical time of the simplified protocol from incision to closure would be significantly shortened and lead to less postsurgical complications. ...
This paper is aimed to present a biomaterials perspective in implant therapy that fosters improved bone response and long‐term biomechanical competence from surgical instrumentation to final prosthetic rehabilitation. Strategies to develop implant surface texturing will be presented and their role as an ad hoc treatment discussed in light of the interplay between surgical instrumentation and implant macrogeometric configuration. Evidence from human retrieved implants in service for several years and from in vivo studies will be used to show how the interplay between surgical instrumentation and implant macrogeometry design affect osseointegration healing pathways, and bone morphologic and long‐term mechanical properties. Also, the planning of implant‐supported prosthetic rehabilitations targeted at long‐term performance will be appraised from a standpoint where personal preferences (eg, cementing or screwing a prosthesis) can very often fail to deliver the best patient care. Lastly, the acknowledgement that every rehabilitation will have its strength degraded over time once in function will be highlighted, since the potential occurrence of even minor failures is rarely presented to patients prior to treatment.
... Modifications in several design features such as thread pitch and thickness have been assessed, aiming to enhance primary stability and avoid excessive strain in bone at implant placement [20,22,23]. Different surgical instrumentation techniques have been also the center of pre-clinical research aiming to achieve predictable osseointegration in low-density bone [24,25]. Among them, the use of nonsubtractive densifying burs that promote the plastic deformation of the bone by rolling or sliding contact has evidenced promising results to enhance the implant's primary stability and to shorten healing times for implants placed in low quality bone [26,27]. ...
The present study aimed to evaluate the effect of dipyridamole, an indirect adenosine 2A receptors (A2AR), on the osseointegration of titanium implants in a large, translational pre-clinical model. Sixty tapered, acid-etched titanium implants, treated with four different coatings ((i) Type I Bovine Collagen (control), (ii) 10 μM dipyridamole (DIPY), (iii) 100 μM DIPY, and (iv) 1000 μM DIPY), were inserted in the vertebral bodies of 15 female sheep (weight ~65 kg). Qualitative and quantitative analysis were performed after 3, 6, and 12 weeks in vivo to assess histological features, and percentages of bone-to-implant contact (%BIC) and bone area fraction occupancy (%BAFO). Data was analyzed using a general linear mixed model analysis with time in vivo and coating as fixed factors. Histomorphometric analysis after 3 weeks in vivo revealed higher BIC for DIPY coated implant groups (10 μM (30.42% ± 10.62), 100 μM (36.41% ± 10.62), and 1000 μM (32.46% ± 10.62)) in comparison to the control group (17.99% ± 5.82). Further, significantly higher BAFO was observed for implants augmented with 1000 μM of DIPY (43.84% ± 9.97) compared to the control group (31.89% ± 5.46). At 6 and 12 weeks, no significant differences were observed among groups. Histological analysis evidenced similar osseointegration features and an intramembranous-type healing pattern for all groups. Qualitative observation corroborated the increased presence of woven bone formation in intimate contact with the surface of the implant and within the threads at 3 weeks with increased concentrations of DIPY. Coating the implant surface with dipyridamole yielded a favorable effect with regard to BIC and BAFO at 3 weeks in vivo. These findings suggest a positive effect of DIPY on the early stages of osseointegration.
... The Simplified Drilling (SD) technique, is an option for site preparation for implant placement, characterized by the use of only two drills: an initial and a final one, with the diameter of the preparations chosen for that site. Among the advantages of the SD technique, we can highlight the reduction in the possibility of perforation angulation error during site preparation and a shorter surgical time [6][7][8][9][10][11][12][13][14][15][16]. ...
Introduction: The predictability of osseointegration depends on a non-traumatic surgical technique that maintains cell viability. It is known that during the drilling osteotomy for implant placement occurs heat generation, being able to influence osseointegration due to thermal damage. The objective of this research was to evaluate and compare the heat generated by the drills during the preparation of surgical sites for implant placement between two different techniques: simplified (Simplified Drilling, SD) and conventional, in an in vitro model. Material and methods: Fifty implant site preparations were performed in segments of bovine ribs, divided into two groups, with the respective drill sequences: control group, conventional preparation, Ø2.0mm spear drill and Ø2.15mm, Ø2.85mm, Ø3.35mm, Ø3.85mm twist drills; SD group, Ø2.15mm and Ø3.85mm twist drills. The measurement of the temperature variation generated by each drill in each group was performed by an infrared thermal camera at three points in the bovine rib segment. Results: The temperature variations at one and thirteen millimeters below the drilling site were, respectively, 0.51±0.64°C and 0.46±0.59°C for the control group, and 0.62±0.76°C and 0.5±0.86°C for the SD group. No statistically significant differences were found between the control and SD groups in relation to heat generation in any of the evaluated points; p=0.288 and p=0.584, respectively for analyzes one and thirteen millimeters below the drilling site. Discussion: The technique of implant site preparation can be simplified, using only two drills in this modality, without showing significant differences in relation to heat generation when compared to the conventional preparation technique.
... Their results showed that both drilling techniques are successful, but single-bur technique was less time consuming and caused less pain. Additionally, Sarendranath et al. [36] compared simplified protocols with conventional ones in terms of biological response. The authors concluded that the simplified procedure provides biological outcomes comparable to those achieved following the conventional one. ...
The aim of this experimental study was to verify thermal diffusion differences, by measuring the maximum temperature achieved with different drill shapes. Synthetic bone blocks of type I density made from solid rigid polyurethane (PUR) foam were used to perform the drilling procedures. The experiment was conducted at three different rotation speeds: 800, 3000 and 5000 rpm. Conical drills (with and without an internal cooling hole) were compared with horizontal drills and disc drills. The temperature during drilling for implant bed preparation was estimated with the use of thermocouples and an infrared (IR) camera. The temperature during drilling with disc cutters for lateral basal implants did not exceed 33 ∘C and the temperature decreased in proportion to higher drill speed. The results indicate that the tested design is safe and will not cause bone overheating.
... The effects of surface engineering and macrogeometric properties of the implant system on secondary stability of endosteal implants have been described in the literature 11 while the effect of surgical drilling techniques on the magnitude of primary stability is a variable that has been investigated to a lesser degree. 1 However, recent work suggests that certain adjustments during surgery, such as drilling protocol sequence, drill velocity, and design, may accelerate implant osseointegration. [12][13][14][15][16] This hypothesis is supported by a previous study, which concludes that the utilization of multi stepped drills when preparing osteotomy, as opposed to conical shaped drills, is seen to increase the primary stability of the implant. 17 Whereas the traditional osteotomy using different step drills is generated by a subtractive method, where bone is drilled away, a unique non excavating drilling sequence has recently been suggested to enhance implant stability via osseodensification drilling. ...
This study investigated the effects of osseodensifica-tion drilling on the stability and osseointegration of machine-cut and acid-etched endosteal implants in low-density bone. Twelve sheep received six implants inserted into the ilium, bilaterally (n = 36 acid-etched, and n = 36 as-machined). Individual animals received three implants of each surface, placed via different surgical techniques: (1) subtractive regular-drilling (R): 2.0 mm pilot, 3.2 and 3.8 mm twist drills); (2) osseodensifi-cation clockwise-drilling (CW): Densah Bur (Versah, Jackson, MI) 2.0 mm pilot, 2.8, and 3.8 mm multifluted tapered burs; and (3) osseodensification counterclockwise-drilling (CCW) Densah Bur 2.0 mm pilot, 2.8 mm, and 3.8 mm multifluted tapered burs. Insertion torque was higher in the CCW and CW-drilling compared to the R-drilling (p < 0.001). Bone-to-implant contact (BIC) was significantly higher for CW (p = 0.024) and CCW-drilling (p = 0.006) compared to the R-drilling technique. For CCW-osseodensification-drilling, no statistical difference between the acid-etched and machine-cut implants at both time points was observed for BIC and BAFO (bone-area-fraction occupancy). Resorbed bone and bone forming precursors, preosteoblasts, were observed at 3-weeks. At 12-weeks, new bone formation was observed in all groups extending to the trabecular region. In low-density bone, endosteal implants inserted via osseodensification-drilling presented higher stability and no osseointegration impairments compared to subtrac-tive regular-drilling technique, regardless of evaluation time or implant surface.
... In Group A, the surgical guide was placed on the polyurethane block and through the metal sleeve; a pilot drill of 2 mm diameter was inserted to drill the pilot hole. Then, a number of drills (2.3 mm, 3 mm, 3.4 mm, 3.8 mm, 4 mm, and 4.2 mm) was used sequentially to increase the diameter of the hole in order to match the diameter of the implant (24). The length of the drills was 16 mm, so a drill stop of 2 mm was added to the drills to match the 12 mm standard implant length. ...
... [5][6][7][8] It is hypothesized that drilling speed (DS) influences osseointegration by influencing biological responses at the bone-implant interface. [3,9,10] One explanation for this is that osseous drilling at 1500 rpm leads to thermal changes that may damage peri-implant tissues. [11] However, results from a recent histologic study [12] showed that increase in the DS (range: 1000-1500 rpm) does not jeopardize the viability of osteoblasts and osteocytes. ...
Background:
There are no studies that have assessed the implant stability quotient (ISQ) values of narrow diameter implants placed in artificial dense bone blocks at varying drilling speeds (DSs).
Purpose:
The aim of the present in vitro experiment was to compare the performance of OSSTELL and Penguin devices to evaluate implant stability at DSs of 800 and 2000 rpm.
Materials and methods:
A total of 360 osteotomies were created in dense artificial bone blocks at DSs of 800 and 2000 rpm. Dental implants from three manufacturers (group-1: NobelActive implants, Nobel Biocare, Yorba Linda, California; group-2: Zimmer, Eztetic-Zimmer implants, Zimmer Biomet Dental, Palm Beach Gardens, Florida; and group-3: Astra Tech implant system, Dentsply Sirona, York, Pennsylvania) were randomly placed in these osteotomies using an insertion torque of 15 Ncm (60 implants/group). Implant stability in all bone blocks immediately following implant placement was evaluated using the OSSTELL and Penguin devices. ISQ values were presented as means ± SD. Statistical significance was set at P < .05.
Results:
There was no significant difference in the ISQ values obtained from the OSSTELL and Penguin devices for implants in groups 1, 2, and 3. There was no significant difference when ISQ values obtained from the OSSTELL device were compared with the Penguin device for narrow diameter dental implants placed in dense bone blocks with osteotomies performed at 800 and 2000 rpm. ISQ values showed statistically significant higher values for OSSTELL compared to Penguin device.
Conclusion:
The OSSTELL and Penguin devices are reliable for the assessment of implant stability in dense artificial bone. Implant design and site-DS does not seem to have a significant impact of implant stability in artificial dense bone blocks.
... [1][2][3] The predictability of osseointegration has been increasing due to the improvement of systems to obtain better results, not only for the well-being of the patient but also to decrease the chances of surgical failure. [4][5][6] In cases where the quality of the bone is Type 3 or 4, [7] the need to increase the amount of bone tissue that will be in contact with the surface of the implant becomes essential to achieve excellent primary stability and to enable immediate loading. [8,9] One possibility for optimizing this process is the modification of the surgical protocol by using the technique of undersized drilling, [1] which has been suggested in the early literature as particularly useful for the immediate loading when inserting the dental implants in low bone quality sites. ...
The advance of surgical techniques and modifications with respect to the surface and macrogeometry of dental implants, such as immediate
and early loading, can help reduce the time of rehabilitation for the patient when excellent primary stability is the primary prerequisite.
Starting from this principle, studies using a novel technique to replace bone‑subtractive drilling have been developed to optimize the implant
site. This new technique, called osseodensification, was developed by Dr. Salah Huwais and patented in 2012. The name of the procedure
suggests the induction of a compression wave at the tip of specially designed drills at the point of contact. This case report suggests that the
clinical and radiographic results obtained could support the hypothesis that a true gain in primary stability as well as a compaction grafting
can be achieved by the use of this technique.
... In all study groups, the drilling speed was 1000 rpm, justifying thermal injury in the group of non-irrigated implants. Sarendranath et al. (24), in a study in dogs, compared conventional drilling with a simplified drilling technique at 400 rpm with irrigation. The results suggest that the simplified procedure yields biological outcomes comparable to those of the conventional procedure. ...
Background:
To compare the technique of high speed drilling with irrigation and low speed drilling without irrigation in order to evaluate the success rate and peri-implant bone loss at 12 months of follow-up.
Material and methods:
A randomized, controlled, parallel-group clinical trial was carried out in patients requiring dental implants to rehabilitate their unitary edentulism. Patients were recruited from the Oral Surgery Unit of the University of Valencia (Spain) between September 2014 and August 2015. Patients who met the inclusion criteria were randomized to two groups: group A (high-speed drilling with irrigation) and group B (low-speed drilling without irrigation). The success rate and peri-implant bone loss were recorded at 12 months of follow-up.
Results:
Twenty-five patients (9 men and 16 women) with 30 implants were enrolled in the study: 15 implants in group A and 15 implants in group B. The mean bone loss of the implants in group A and group B was 0.83 ± 0.73 mm and 0.62 ± 0.70 mm, respectively (p> 0.05). In the maxilla, the bone loss was 1.04 ± 0.63 mm in group A and 0.71 ± 0.36 mm in group B (p> 0.05), while bone loss in the mandible was 0.59 ± 0.80 mm in group A and 0.69 ± 0.77 mm in group B (p> 0.05). The implant success rate at 12 months was 93.3% in group A and 100% in group B.
Conclusions:
Within the limitations of the study, the low-speed drilling technique presented peri-implant bone loss outcomes similar to those of the conventional drilling technique at 12 months of follow-up.
... However, the number of investigations concerning surgical instrumentation effects on early fixation and osseointegration is at least one order of magnitude smaller relative to other design parameters (Coelho and Jimbo, 2014). The limited body of literature addressing drilling technique and its effects on osseointegration suggests that implant stability can in fact be hastened by drilling protocol alterations in both maxillofacial and orthopedic settings (Galli et al., 2015a(Galli et al., , 2015bGiro et al., 2011Giro et al., , 2013Sarendranath et al., 2015;Yeniyol et al., 2013). Specific to spine procedures, reviews in literature have primarily focused on the limited perspective of materials available to surgeons for clinical orthopedic applications (Rao et al., 2014). ...
Integration between implant and bone is an essential concept for osseous healing requiring hardware placement. A novel approach to hardware implantation, termed osseodensification, is described here as an effective alternative. 12 sheep averaging 65 kg had fixation devices installed in their C2, C3, and C4 vertebral bodies; each device measured 4mm diameter x 10mm length. The left-sided vertebral body devices were implanted using regular surgical drilling (R) while the right-sided devices were implanted using osseodensification drilling (OD). The C2 and C4 vertebra provided the t=0 in vivo time point, while the C3 vertebra provided the t = 3 and t = 6 week time points, in vivo. Structural competence of hardware was measured using biomechanical testing of pullout strength, while the quality and degree of new bone formation and remodeling was assessed via histomorphometry. Pullout strength demonstrated osseodensification drilling to provide superior anchoring when compared to the control group collapsed over time with statistical significance (p<0.01). On Wilcoxon rank signed test, C2 and C4 specimens demonstrated significance when comparing device pullout at a (p=0.031) for both, and C3 pullout tests at 3 and 6 weeks collapsed over time had significance with as well (p=0.027). Percent bone-to-implant contact (%BIC) analysis as a function of drilling technique demonstrated a OD group with significantly higher values relative to the R group (p<0.01). Similarly, bone-area-fraction-occupancy (BAFO) analysis presented with significantly higher values for the OD group compared to the R group (p=0.024). As a function of time, between 0 and 3 weeks, a decrease in BAFO was observed, a trend that reversed between 3 and 6 weeks, resulting in a BAFO value roughly equivalent to the t=0 percentage, which was attributed to an initial loss of bone fraction due to remodeling, followed by regaining of bone fraction via production of woven bone. Histomorphological data demonstrated autologous bone chips in the OD group with greater frequency relative to the control, which acted as nucleating surfaces promoting new bone formation around the implants, providing superior stability and greater bone density. This alternative approach to a critical component of hardware implantation encourages assessment of current surgical approaches to hardware implantation.
... Surface engineering and implant macrogeometric engineering have been the most investigated variables with respect to how endosteal implant temporal stability is affected, whereas the literature concerning drilling effects on implant primary stability and osseointegration is smaller by at least one order of magnitude . While a substantially smaller body of literature concerns surgical instrumentation methods effects on osseointegration, recent work has pointed that osseointegration may be accelerated through adjustments in drilling protocol sequence, drill velocity, and design (Galli et al., 2015;Giro et al., 2011Giro et al., , 2013Sarendranath et al., 2015;Yeniyol et al., 2013). A previous investigation has demonstrated that site preparation with multi stepped drills have increased implant primary stability relative to conical shaped drills further supporting the key role that surgical instrumentation plays on the overall bone/ implant system biomechanical behavior (Abboud et al., 2015). ...
A bone drilling concept, namely osseodensification, has been introduced for the placement of endosteal implants to increase primary stability through densification of the osteotomy walls. This study investigated the effect of osseodensification on the initial stability and early osseointegration of conical and parallel walled endosteal implants in low density bone. Five male sheep were used. Six implants were inserted in the ilium, bilaterally, totalling 30 implants (n=15 conical, and n=15 parallel). Each animal received 3 implants of each type, inserted into bone sites prepared as follows: (i) regular-drilling (R: 2 mm pilot, 3.2 mm, and 3.8 mm twist drills), (ii) clockwise osseodensification (CW), and (iii) counterclockwise (CCW) osseodensification drilling with Densah Bur (Versah, Jackson, MI, USA): 2.0 mm pilot, 2.8 mm, and 3.8 mm multi-fluted burs. Insertion torque as a function of implant type and drilling technique, revealed higher values for osseodensification relative to R-drilling, regardless of implant macrogeometry. A significantly higher bone-to-implant contact (BIC) for both osseodensification techniques (p< 0.05) was observed compared to R-drilling. There was no statistical difference in BIC as a function of implant type (p=0.58), nor in bone-area-fraction occupancy (BAFO) as a function of drilling technique (p=0.22), but there were higher levels of BAFO for parallel than conic implants (p= 0.001). Six weeks after surgery, new bone formation was observed in groups. Bone chips in proximity with the implants were seldom observed in the R-drilling group, but commonly observed in the CW, and more frequently under the CCW osseodensification technique. In low-density bone, endosteal implants present higher insertion torque levels when placed in osseodensification drilling sites, with no osseointegration impairment compared to standard subtractive drilling methods.
Implant site preparation is a critical stage of implant surgery that may underpin various complications related to implant surgery. This review discusses the latest available scientific information on risk factors related to implant site preparation. The role of the drilling process in relation to the density of the available alveolar bone, the effects of insertion torque on peri‐implant osseous healing, and implant‐related variables such as macrodesign and implant‐abutment connection are all factors that can influence implant success. Novel information that links osteotomy characteristics (including methods to improve implant initial stability, the impact of drilling speed, and increase of the implant insertion torque modifying the bone‐implant interface) with the appropriate instrumentation techniques will be discussed, as well as interactions at the bone‐biomaterial interface that may lead to biologic complications mediated by implant dissolution products.
Statement of problem
Custom mini-implants are needed for edentulous patients with extensive mandibular deficiencies where endosteal placement is not possible. However, the best design for these mini-implants is unclear.
Purpose
The purpose of this in vitro study was to develop 2 dental mini-implant designs to support mandibular overdentures and evaluate the effect of their geometries on primary stability and stress distribution.
Material and methods
Two mini-implant designs were developed with changes in the shape, size, and arrangement of threads and chamfers. The experimental mini-implants were made of Grade V titanium alloy (Ti-6Al-4V), (Ø2.0×10 mm) and submitted to a nanoscale surface treatment. Thirty mini-implants (n=10) were placed into fresh swine bones: experimental-threaded, experimental-helical, and a commercially available product model (Intra-Lock System) as the control. The biomechanical evaluations of the experimental mini-implants were compared with those of the control in terms of primary stability, through insertion torque (IT), and with the pullout test. The analysis of stress distribution was performed by using the method of 3D digital image correlation under 250-N axial load and 100-N oblique (30-degree angled model) load. The data were analyzed by ANOVA and the Tukey HSD test (α=.05).
Results
The IT and pullout test presented a statistically significant difference for all mini-implants (P<.05), with higher IT for the experimental-threaded and maximum pullout force for the control, followed by threaded (P=.001) and helical (P=.001). Regarding the 3D digital image correlation, a lower incidence of stress was found in the cervical third for all mini-implants. No statistically significant differences were found between the designs evaluated (P>.05).
Conclusions
Comparing the experimental mini-implants with the commercially available control, the experimental-threaded model presented greater primary stability, and all mini-implants showed less stress in the cervical third.
Amaç: Bu çalışmanın amacı düşük devir ve yüksek devir ile hazırlanmış yuvalara yerleştirilmiş diş implantlarının primer stabilite değerlerinin karşılaştırılmasıdır. Gereç ve Yöntemler: Bu ex vivo çalışmada taze sığır kemiğine 20 adet implant yerleştirilmiştir. İmplant yuvalarının 10 tanesi 800 rpm ile 10 tanesi ise 50 rpm ile hazırlanmıştır. Çalışmada kullanılan tüm implantlar 3.7 mm çap ve 10 mm boya sahiptir. İmplantlara PenguinRFA cihazının ölçüm ucu (multipeg) bağlanmış ve ölçümler kemiğin uzun eksenine paralel ve dik olacak şekilde yapılmıştır. Ölçümler her yön için üçer defa tekrarlanmış ve ortalama bir ISQ değeri hesaplanmıştır. Sonuçların ortalaması alınmış ve verilerin iki grup arası karşılaştırmalarında Student t test kullanılmıştır. Bulgular: 800 rpm protokolünün ISQ ortalaması, 50 rpm protokolünden istatistiksel olarak anlamlı düzeyde düşük bulunmuştur (p<0.05). Sonuç: Bu çalışmanın sınırları dahilinde düşük devir ile hazırlanan yuvalara yerleştirilen implantların ISQ ortalaması, geleneksel yöntemle (800 rpm) hazırlanan yuvalara yerleştirilen implantların ISQ ortalamasından istatistiksel olarak anlamlı düzeyde yüksek bulunmuştur. Bununla birlikte bu sonuçların doğrulanması için randomize kontrollü çalışmalara ihtiyaç vardır.
Objective:
The aim of this in vivo study is to compare the osseointegration of endosteal implants placed in atrophic mandibular alveolar ridges with alveolar ridge expansion surgical protocol via an experimental osseodensification drilling versus conventional osteotome technique.
Methods:
Twelve endosteal implants, 4 mm × 13 mm, were placed in porcine models in horizontally atrophic mandibular ridges subsequent to prior extraction of premolars. Implants were placed with osseodensification drilling technique as the experimental group (n = 6) and osteotome site preparation as the control group (n = 6). After 4 weeks of healing, samples were retrieved and stained with Stevenel's Blue and Van Gieson's Picro Fuschin for histologic evaluation. Quantitative analysis via bone-to-implant contact (BIC%) and bone area fraction occupancy (BAFO%) were obtained as mean values with corresponding 95% confidence interval. A significant omnibus test, post-hoc comparison of the 2 drilling techniques' mean values was accomplished using a pooled estimate of the standard error with P-value set at 0.05.
Results:
The mean BIC% value was approximately 62.5% in the osseodensification group, and 31.4% in the regular instrumentation group. Statistical analysis showed a significant effect of the drilling technique (P = 0.018). There was no statistical difference in BAFO as a function of drilling technique (P = 0.198).
Conclusion:
The combined osseodensification drilling-alveolar ridge expansion technique showed increased evidence of osseointegration and implant primary stability from a histologic and biomechanical standpoint, respectively. Future studies will focus on expanding the sample size as well as the timeline of the study to allow investigation of long-term prognosis of this novel technique.
Objectives:
To test the hypothesis that there would be no difference in heat production by reducing the number of drills during the implant site preparation relative to conventional drilling sequence.
Methods:
A total of 120 implant site preparations with 3 different diameters (3.6, 4.3, and 4.6 mm) were performed on bovine ribs. Within the same diameter group, half of the preparations were performed by a simplified drilling procedure (pilot drill + final diameter drill) and other half using the conventional drilling protocol (pilot drill followed by graduated series of drills to widen the site). Heat production by different drilling techniques was evaluated by measuring the bone temperature using k-type thermocouple and a sensitive thermometer before and after each drill.
Results:
Mean for maximum temperature increase during site preparation of the 3.6, 4.3, and 4.6-mm implants was 2.45, 2.60, and 2.95° when the site was prepared by the simplified procedure, whereas it was 2.85, 3.10, and 3.60° for the sites prepared by the conventional technique, respectively. No significant difference in temperature increase was found when implants of the 3 different diameters were prepared either by the conventional or simplified drilling procedure.
Conclusions:
The simplified drilling technique produced similar amount of heat comparable to the conventional technique that proved the initial hypothesis.
Objectives:
To test the hypothesis that there would be no difference in heat generation by reducing the number of drills during the implant site preparation relative to conventional drilling sequence.
Methods:
A total of 80 implant site preparations with 2 different diameters (5.6 and 6.2 mm) were performed on bovine ribs. Within the same diameter group, half of the preparations were performed by a simplified drilling procedure (pilot drill + final diameter drill) and the other half using the conventional drilling protocol, where multiple drills of increasing diameter were utilized. Heat production by different drilling techniques was evaluated by measuring the bone temperature using K-type thermocouple and a sensitive thermometer before and after each drill.
Results:
Mean for maximum temperature increase during site preparation of the 5.6- and 6.2-mm implants was 2.20°C, and it was 2.55°C when the site was prepared by the simplified procedure, whereas it was 2.80°C and 2.95°C for the sites prepared by the conventional technique, respectively. No significant difference in temperature increase was found when implants of the 2 chosen diameters were prepared either by the conventional or simplified drilling procedure.
Conclusions:
The simplified drilling protocol produces similar amount of heat comparable to the conventional technique, which proved the initial hypothesis.
Objectives. To test the hypothesis that there would be no differences in osseointegration by reducing the number of drills for site preparation relative to conventional drilling sequence. Methods. Seventy-two implants were bilaterally placed in the tibia of 18 beagle dogs and remained for 1, 3, and 5 weeks. Thirty-six implants were 3.75 mm in diameter and the other 36 were 4.2 mm. Half of the implants of each diameter were placed under a simplified technique (pilot drill + final diameter drill) and the other half were placed under conventional drilling where multiple drills of increasing diameter were utilized. After euthanisation, the bone-implant samples were processed and referred to histological analysis. Bone-to-implant contact (BIC) and bone-area-fraction occupancy (BAFO) were assessed. Statistical analyses were performed by GLM ANOVA at 95% level of significance considering implant diameter, time in vivo, and drilling procedure as independent variables and BIC and BAFO as the dependent variables. Results. Both techniques led to implant integration. No differences in BIC and BAFO were observed between drilling procedures as time elapsed in vivo. Conclusions. The simplified drilling protocol presented comparable osseointegration outcomes to the conventional protocol, which proved the initial hypothesis.
No abstract available.
Micromotion and fretting damages at the dental implant/bone interface are neglected for the limitation of check methods, but it is particularly important for the initial success of osseointegration and the life time of dental implant. This review article describes the scientific documentation of micromotion and fretting damages on the dental implant/bone interface. The fretting amplitude is less than 30 µm in vitro and the damage in the interface is acceptable. While in vivo, the micromotion's effect is the combination of damage in tissue level and the real biological reaction.International Journal of Oral Science (2012) 4, doi:10.1038/ijos.2012.68; published online 21 December 2012.
Background:
To date, some experimental studies have addressed the effect of bone drilling technique and sequence on dental implant osseointegration. In the present study, the authors hypothesize that there would be no differences in osseointegration when reducing the number of drills for osteotomy compared to the conventional drilling protocols.
Methods:
Seventy-two implants (diameters 3.75 mm and 4.2 mm; n = 36 for each diameter) were bilaterally placed in the tibia of 18 beagles for 1, 3, and 5 weeks. Half of the implants of each diameter were placed using a simplified drilling procedure (pilot and final drill), and the other half were placed using a conventional drilling procedure (all drills in sequence). The retrieved samples were subjected to histologic and histomorphometric evaluation.
Results:
Histology showed that new bone formed around the implant, and inflammation or bone resorption was not evident for both groups. Histomorphometrically, the simplified group presented significantly higher bone-to-implant contact and bone area fraction occupancy compared to the conventional group after 1 week; however, no differences were detected at 3 and 5 weeks.
Conclusion:
Bone responses to the implant with the simplified protocol can be comparable to the conventional protocol.
The purpose of this study was to evaluate the temperature change during low-speed drilling using infrared thermography.
Pig ribs were used to provide cortical bone of a similar quality to human mandible. Heat production by three implant drill systems (two conventional drilling systems and one low-speed drilling system) was evaluated by measuring the bone temperature using infrared thermography. Each system had two different bur sizes. The drill systems used were twist drill (2.0 mm/2.5 mm), which establishes the direction of the implant, and finally a 3.0 mm-pilot drill. Thermal images were recorded using the IRI1001 system (Infrared Integrated Systems Ltd.). Baseline temperature was 31±1ºC. Measurements were repeated 10 times, and a static load of 10 kg was applied while drilling. Data were analyzed using descriptive statistics. Statistical analysis was conducted with two-way ANOVA.
Mean values (n=10 drill sequences) for maximum recorded temperature (Max TºC), change in temperature (ΔTºC) from baseline were as follows. The changes in temperature (ΔTºC) were 1.57ºC and 2.46ºC for the lowest and the highest values, respectively. Drilling at 50 rpm without irrigation did not produce overheating. There was no significant difference in heat production between the 3 implant drill systems (p>0.05). No implant drill system produced heat exceeding 47ºC, which is the critical temperature for bone necrosis during low-speed drilling. Low-speed drilling without irrigation could be used during implant site preparation.
Osseointegration refers to a direct structural and functional connection between ordered, living bone and the surface of a load-carrying implant. Currently, an implant is considered as osseointegrated when there is no progressive relative movement between the implant and the bone with which it has direct contact. A direct bone contact as observed histologically may be indicative of the lack of a local or systemic biological response to that surface. It is therefore proposed that osseointegration is not the result of an advantageous biological tissue response but rather the lack of a negative tissue response. The rationale of the present review is to evaluate the basic science work performed on the concept of biology of osseointegration, and to discuss the specific factors as they may relate to osseous healing around an implant.
A total of 2895 threaded, cylindrical titanium implants have been inserted into the mandible or the maxilla and 124 similar implants have been installed in the tibial, temporal or iliac bones in man for various bone restorative procedures. The titanium screws were implanted without the use of cement, using a meticulous technique aiming at osseointegration--a direct contact between living bone and implant. Thirty-eight stable and integrated screws were removed for various reasons from 18 patients. The interface zone between bone and implant was investigated using X-rays, SEM, TEM and histology. The SEM study showed a very close spatial relationship between titanium and bone. The pattern of the anchorage of collagen filaments to titanium appeared to be similar to that of Sharpey's fibres to bone. No wear products were seen in the bone or soft tissues in spite of implant loading times up to 90 months. The soft tissues were also closely adhered to the titanium implant, thereby forming a biological seal, preventing microorganism infiltration along the implant. The implants in many cases had been allowed to permanently penetrate the gingiva and skin. This caused no adverse tissue effects. An intact bone-implant interface was analyzed by TEM, revealing a direct bone-to-implant interface contact also at the electron microscopic level, thereby suggesting the possibility of a direct chemical bonding between bone and titanium. It is concluded that the technique of osseointegration is a reliable type of cement-free bone anchorage for permanent prosthetic tissue substitutes. At present, this technique is being tried in clinical joint reconstruction. In order to achieve and to maintain such a direct contact between living bone and implant, threaded, unalloyed titanium screws of defined finish and geometry were inserted using a delicate surgical technique and were allowed to heal in situ, without loading, for a period of at least 3--4 months.
During the drilling of the bone, the temperature could increase above 47 degrees C and cause irreversible osteonecrosis. The result is weakened contact of implants with bone and possible loss of rigid fixation. The aim of this study was to find an optimal condition where the increase in bone temperature during bone drilling process would be minimal.
Influence of different drill parameters was evaluated on the increase of bone temperature. Drill diameters were 2.5, 3.2 and 4.5 mm; drill speed 188, 462, 1,140 and 1,820 rpm; feed-rate 24, 56, 84 and 196 mm/min; drill point angle 80 degrees , 100 degrees and 120 degrees and external irrigation with water of 26 degrees C.
Combinations of drill speed and drill diameter with the use of external irrigation produced temperatures far below critical. Without external irrigation, temperature values for the same combination of parameters ranged 31.4-55.5 degrees C. Temperatures above critical were recorded using 4.5 mm drill with higher drill speeds (1,140 and 1,820 rpm). There was no statistical significance of different drill point angles on the increase or decrease of bone temperature. The higher the feed-rate the lower the increase of bone temperature.
The external irrigation is the most important cooling factor. With all combinations of parameters used, external irrigation maintained the bone temperature below 47 degrees C. The increase in drill diameter and drill speed caused increase in bone temperature. The changes in drill point angle did not show significant influence in the increase of the bone temperature. With the increase in feed-rate, increase in bone temperature is lower.
Information concerning the effects of the implant cutting flute design on initial stability and its influence on osseointegration in vivo is limited. This study evaluated the early effects of implants with a specific cutting flute design placed in the sheep mandible. Forty-eight dental implants with two different macro-geometries (24 with a specific cutting flute design – Blossom group; 24 with a self-tapping design – DT group) were inserted into the mandibular bodies of six sheep; the maximum insertion torque was recorded. Samples were retrieved and processed for histomorphometric analysis after 3 and 6 weeks. The mean insertion torque was lower for Blossom implants (P < 0.001). No differences in histomorphometric results were observed between the groups. At 3 weeks, P = 0.58 for bone-to-implant contact (BIC) and P = 0.52 for bone area fraction occupied (BAFO); at 6 weeks, P = 0.55 for BIC and P = 0.45 for BAFO. While no histomorphometric differences were observed, ground sections showed different healing patterns between the implants, with better peri-implant bone organization around those with the specific cutting flute design (Blossom group). Implants with the modified cutting flute design had a significantly reduced insertion torque compared to the DT implants with a traditional cutting thread, and resulted in a different healing pattern.
EXECUTIVE SUMMARYThe “Guideline for Prevention of Surgical Site Infection, 1999” presents the Centers for Disease Control and Prevention (CDC)’s recommendations for the prevention of surgical site infections (SSIs), formerly called surgical wound infections. This two-part guideline updates and replaces previous guidelines.1 and 2 Part I, “Surgical Site Infection: An Overview,” describes the epidemiology, definitions, microbiology, pathogenesis, and surveillance of SSIs. Included is a detailed discussion of the pre-, intra-, and postoperative issues relevant to SSI genesis. Part II, “Recommendations for Prevention of Surgical Site Infection,” represents the consensus of the Hospital Infection Control Practices Advisory Committee (HICPAC) regarding strategies for the prevention of SSIs.3 Whenever possible, the recommendations in Part II are based on data from well-designed scientific studies. However, there are a limited number of studies that clearly validate risk factors and prevention measures for SSI. By necessity, available studies have often been conducted in narrowly defined patient populations or for specific kinds of operations, making generalization of their findings to all specialties and types of operations potentially problematic. This is especially true regarding the implementation of SSI prevention measures. Finally, some of the infection control practices routinely used by surgical teams cannot be rigorously studied for ethical or logistical reasons (e.g., wearing vs not wearing gloves). Thus, some of the recommendations in Part II are based on a strong theoretical rationale and suggestive evidence in the absence of confirmatory scientific knowledge. It has been estimated that approximately 75% of all operations in the United States will be performed in “ambulatory,” “same-day,” or “outpatient” operating rooms by the turn of the century.4 In recommending various SSI prevention methods, this document makes no distinction between surgical care delivered in such settings and that provided in conventional inpatient operating rooms. This document is primarily intended for use by surgeons, operating room nurses, postoperative inpatient and clinic nurses, infection control professionals, anesthesiologists, healthcare epidemiologists, and other personnel directly responsible for the prevention of nosocomial infections. This document does not:•Specifically address issues unique to burns, trauma, transplant procedures, or transmission of bloodborne pathogens from healthcare worker to patient, nor does it specifically address details of SSI prevention in pediatric surgical practice. It has been recently shown in a multicenter study of pediatric surgical patients that characteristics related to the operations are more important than those related to the physiologic status of the patients.5 In general, all SSI prevention measures effective in adult surgical care are indicated in pediatric surgical care.•Specifically address procedures performed outside of the operating room (e.g., endoscopic procedures), nor does it provide guidance for infection prevention for invasive procedures such as cardiac catheterization or interventional radiology. Nonetheless, it is likely that many SSI prevention strategies also could be applied or adapted to reduce infectious complications associated with these procedures.•Specifically recommend SSI prevention methods unique to minimally invasive operations (i.e., laparoscopic surgery). Available SSI surveillance data indicate that laparoscopic operations generally have a lower or comparable SSI risk when contrasted to open operations.6, 7, 8, 9, 10 and 11 SSI prevention measures applicable in open operations (e.g., open cholecystectomy) are indicated for their laparoscopic counterparts (e.g., laparoscopic cholecystectomy).•Recommend specific antiseptic agents for patient preoperative skin preparations or for healthcare worker hand/forearm antisepsis. Hospitals should choose from products recommended for these activities in the latest Food and Drug Administration (FDA) monograph. 12
Recently published reports(1-5) as well as a consensus statement(6) have suggested an alarming increase in inflammatory responses around dental implants that are accompanied by variable levels of marginal bone loss. These responses are popularly referred to as an escalating disease entity-so-called "peri-implantitis." This emerging mindset poses serious questions for the long-term viability of the osseointegration technique if the condition indeed exists in a primary form. However, the bulk of the existing literature related to osseointegration has not described peri-implant gingivitis with accompanying marginal bone changes in such dramatic terms. In fact, it has been well documented that failure to induce and maintain long-term osseointegration actually occurs in less than 5% of treated patients. Moreover, clinical outcome studies have not routinely described complications related to progressive soft or hard tissue deterioration. Consequently, the current emphasis on the significance of peri-implant bone loss represents either an ignored phenomenon or is an overtly pessimistic interpretation of or emphasis on a somewhat rarely occurring event. In an effort to determine which of these dichotomous occurrences more closely resembles the truth, an independent initiative sought to evaluate questions related to soft and hard tissue damage adjacent to dental implants.
No abstract available.
The purpose was to assess thermal changes and drill wear in bovine bone tissue with the use of twisted stainless steel and zirconia-based drills, during implant site preparation.
A total of 100 implant site preparations were performed on bovine ribs using a surgical unit linked to a testing device, in order to standardize/simulate implant drilling procedures. Bone temperature variations and drilling force were recorded when drilling at a depth of 8 and 10 mm. A constant irrigation of 50 ml/min. (21±1°C) and drilling speed of 800 r.p.m. were used. Scanning electron microscopy analysis was preformed prior and after drilling.
Mean temperature increase with both drills at 8 mm was 0.9°C and at 10 mm was 2°C (P<0.0001). Statistical significant higher bone temperatures were obtained with stainless steel drill (1.6°C), when comparing with the ceramic drill (1.3°C) (P<0.05). Temperature increase was correlated with higher number of perforations (P<0.05) and drilling load applied. There was no significant association between drilling force applied and temperature increase by either drill or at either depth. No severe signs of wear of either drill were detected after 50 uses.
Drill material and design, number of uses, depth and drilling load applied appear to influence bone temperature variations during implant site preparation. Drilling depth was a predominant factor in bone temperature increase. Both drills can be used up to 50 times without producing harmful temperatures to bone tissue or severe signs of wear and deformation.
Thermal injury during implant bed preparation has a major influence on implant osseointegration and survival. This study investigated the effectiveness of the temperature of the saline solution used for heat control during drilling.
Fresh frozen edentulous segments of bovine mandibles were sectioned into 12 x 6 cm pieces. Thermoresistors were placed 0.5 mm from the drilling cavity walls, at depths of 3, 7, and 12 mm. Signals from the three thermoresistors were analyzed using ORIGIN 5.0 software.
The maximum temperatures during drilling without irrigation were 50.9, 47.4, and 38.1 degrees C at depths of 3, 7, and 12 mm, respectively. With irrigation using saline at 25 and 10 degrees C, the maximum temperatures at a depth of 12 mm were 37.4 and 36.3 degrees C, respectively. All other measurements with both 25 and 10 degrees C saline were below body temperature.
This experimental in vitro study showed that more heat was generated in the superficial part of the drilling cavity than at the bottom. Therefore, external irrigation at room temperature can provide sufficient cooling during drilling. Lower temperature saline was more effective in cooling the bone, and irrigation of the site should be continued between the drilling steps.
Preformed bone grafts (PBG) were inserted in large jaw bone defects in 5 patients. The grafts in all cases healed-in rapidly. Two patients died of metastatic sarcoma 1 year after grafting. The other patients are healthy with excellently functioning grafts 3, 5 and 8 years after transplantation, respectively. The preformation of bone grafts is, however, regarded as a resource consuming technique that should be used only in selected cases of mandibular reconstruction. Particularly in young individuals, the better results achieved with PBG, in comparison with other types of grafts, seem to justify the more complicated surgical procedure. Apart from a description of the preformation technique, the present paper also introduces advice as how to minimally traumatize the hard tissues in bone graft surgery.
Measurements of bone temperature rise were recorded during drilling of bovine cortical bone specimens. A surgical drill (Stryker-100) was fitted with a custom-designed speedometer for monitoring the rotational speed during the drilling, and the drill was mounted on a specially constructed drill press. The tests were conducted in 36 specimens at variable speeds (20000-100000 rpm) and at different constant forces (1.5-9.0 N) which were applied by placing weights on the drill platform. The results revealed that the temperature rise and the duration of temperature elevation decreased with speed and force, suggesting that drilling at high speed and with large load is much more desirable than previously thought.
In this prospective study 47 edentulous patients were treated with mandibular fixed prostheses supported by osseointegrated Brånemark implants and followed for 12 to 15 years. Three (1%) of the 273 inserted implants were lost, two before and one six years after placement of the fixed prosthesis. The cumulative success rate (CSR) of the implants was 98.9% both after 10 and 15 years. None of the fixed prostheses was lost and at the last follow-up, all patients had stable fixed prostheses in function (CSR 100%). The marginal bone loss around the implants was small, on average 0.5 mm during the first post surgical year and thereafter about 0.05 mm annually. More bone was lost around the anterior implants than around the most posterior ones. Smoking and poor oral hygiene had significant influence on bone loss, while occlusal loading factors such as maximal bite force, tooth clenching and length of cantilevers were of minor importance. It is concluded that the long-term results of the mandibular implant treatment were extremely successful, regarding both the fixed prostheses and implant stability. Bone resorption around the implants, albeit limited, was influenced by several factors, smoking and oral hygiene appeared to be most important.
In Part I of this two-part study, the authors investigated heat production during osteotomy drilling at three different speeds, and determined that high-speed drilling produced the least heat when using 700 XL carbide burs. Part II of the study histologically examines the rate and quality of healing after drilling osteotomies at the three speeds in the mandible. Osteotomies were histologically examined 2, 4, and 6 weeks postoperatively. Histologic findings suggested that in the initial 6 weeks, the rate of healing and quality of new bone formation were higher after high-speed drilling than after low- or intermediate-speed drilling. These results, when considered with the results reported in Part I in which a 4.3 degrees C difference in heat production was observed between the speeds, seem to imply a relationship between heat production and healing for osteotomy drilling.
The amount of heat produced by dental implant osteotomy (receptor site) preparation at different speeds and the effects of heat production on the prognosis of implant treatment are controversial. In Part I of this two-part study, heat production was measured in vivo during osteotomy preparation at low (maximum 2,000 rpm), intermediate (maximum 30,000 rpm), and high (maximum 400,000 rpm) speeds in the rabbit tibia, and an inverse relationship was observed between drill speed and heat production. For the measurement of heat production (Part I), a thermocouple probe was inserted into a prepared receptor site in the anteromedial aspect of the tibial metaphysis. Temperature was recorded while an osteotomy was drilled 1 mm from the thermocouple receptor site. Distilled water was used as coolant in conjunction with all drilling, and all osteotomies were prepared by a single researcher to eliminate the variable of interoperator difference in technique. An inverse relationship was observed between drill speed and heat production. An analysis of variance indicated significant differences in heat production among the three drilling speeds (P < 0.05). The results of Part 1 of this study indicate that for the configuration and material of bur used, the high-speed range minimizes heat production.
A significant no-load healing period is the generally accepted prerequisite for osseointegration in dental implantology. The aim of this article was to examine whether this no-load healing period is validated by the experimental literature. In vivo histological data was scrutinized to identify the effect of early loading protocols on the bone-implant interface. Several loading modes were identified. They were categorized into groups according to implant design and the type of prosthetic reconstruction, and by their ability to introduce a distinct magnitude of motion at the interface. Specific histologic responses of early loaded implants (i.e., fibrous repair or osseointegration) were suggested to be directly related to the specific combinations of the above parameters. Early loading per se was not found to be detrimental to osseointegration. Specifically, only excessive micromotion was directly implicated in the formation of fibrous encapsulation. The literature suggests that there is a critical threshold of micromotion above which fibrous encapsulation prevails over osseointegration. This critical level, however, was not zero micromotion as generally interpreted. Instead, the tolerated micromotion threshold was found to lie somewhere between 50 and 150 microns. Suggestions are made for the earliest loading time that achieves osseointegration.
EXECUTIVE SUMMARY The "Guideline for Prevention of Surgical Site Infection, 1999" presents the Centers for Disease Control and Prevention (CDC)'s recommendations for the prevention of surgical site infections (SSIs), formerly called surgical wound infections. This two-part guideline updates and replaces previous guidelines.1,2 Part I, "Surgical Site Infection: An Overview," describes the epidemiology, definitions, microbiology, pathogenesis, and surveillance of SSIs. Included is a detailed discussion of the pre-, intra-, and postoperative issues relevant to SSI genesis. Part II, "Recommendations for Prevention of Surgical Site Infection," represents the consensus of the Hospital Infection Control Practices Advisory Committee (HICPAC) regarding strategies for the prevention of SSIs.3 Whenever possible, the recommendations in Part II are based on data from well-designed scientific studies. However, there are a limited number of studies that clearly validate risk factors and prevention measures for SSI. By necessity, available studies have often been conducted in narrowly defined patient populations or for specific kinds of operations, making generalization of their findings to all specialties and types of operations potentially problematic. This is especially true regarding the implementation of SSI prevention measures. Finally, some of the infection control practices routinely used by surgical teams cannot be rigorously studied for ethical or logistical reasons (e.g., wearing vs not wearing gloves). Thus, some of the recommendations in Part II are based on a strong theoretical rationale and suggestive evidence in the absence of confirmatory scientific knowledge.It has been estimated that approximately 75% of all operations in the United States will be performed in "ambulatory," "same-day," or "outpatient" operating rooms by the turn of the century.4 In recommending various SSI prevention methods, this document makes no distinction between surgical care delivered in such settings and that provided in conventional inpatient operating rooms. This document is primarily intended for use by surgeons, operating room nurses, postoperative inpatient and clinic nurses, infection control professionals, anesthesiologists, healthcare epidemiologists, and other personnel directly responsible for the prevention of nosocomial infections. This document does not: Specifically address issues unique to burns, trauma, transplant procedures, or transmission of bloodborne pathogens from healthcare worker to patient, nor does it specifically address details of SSI prevention in pediatric surgical practice. It has been recently shown in a multicenter study of pediatric surgical patients that characteristics related to the operations are more important than those related to the physiologic status of the patients.5 In general, all SSI prevention measures effective in adult surgical care are indicated in pediatric surgical care. Specifically address procedures performed outside of the operating room (e.g., endoscopic procedures), nor does it provide guidance for infection prevention for invasive procedures such as cardiac catheterization or interventional radiology. Nonetheless, it is likely that many SSI prevention strategies also could be applied or adapted to reduce infectious complications associated with these procedures. Specifically recommend SSI prevention methods unique to minimally invasive operations (i.e., laparoscopic surgery). Available SSI surveillance data indicate that laparoscopic operations generally have a lower or comparable SSI risk when contrasted to open operations.6-11 SSI prevention measures applicable in open operations (e.g., open cholecystectomy) are indicated for their laparoscopic counterparts (e.g., laparoscopic cholecystectomy). Recommend specific antiseptic agents for patient preoperative skin preparations or for healthcare worker hand/forearm antisepsis. Hospitals should choose from products recommended for these activitie
In the preparation of osseointegrated dental implant sites, the use of bone drilling with conventional external irrigation has been shown to be thermally non-injurious to bovine bone, when employed as a model for dental implantology. The use of internal irrigation drilling systems is promoted on the basis of improved delivery of coolant to the bone/drill interface, which should subsequently improve local debridement and cooling, and therefore reduce thermal insults to the bone. The aim of this bovine model study was to compare the temperatures that were generated with external and internal irrigation systems during bone preparation for dental implants. A constant drill load of 1.7 kg was applied throughout the drilling procedures via a drilling rig. The burs that were used for both irrigation methods were a 2 mm twist drill for cutting the channel and a 3.25 mm drill for trephining this channel. The principal recorded parameter was the change in temperature generated via the drilling procedure. The 2 mm twist drills produced a maximum change in temperature of only 3.0 degrees C and 3.1 degrees C for the internal and external irrigation systems, respectively. Maximum changes for the 3.25 mm drills were 1.34 degrees C and 1.62 degrees C, respectively. Using the t-test, no statistical benefit was observed for one irrigant delivery system over the other. The clinical benefit of using the more expensive internal irrigation systems is therefore deemed unjustifiable, on the grounds that these systems do not appear to reduce the thermal challenge to the bone over and above that of simple flood irrigation.
The purpose of this study was to measure the heat generated from 3 drilling speeds (1,225, 1,667, and 2,500 rpm) using the armamentarium of 4 implant systems.
The mean rise in temperature, the time of drilling, and the time needed for pig jaw bone to return to the baseline temperature were monitored using 4 thermocouple technology.
The mean rise in temperature, the time of drilling, and the time needed for the specimens to return to the baseline temperature were lower at 2,500 rpm than at 1,667 or 1,225 rpm (P < or =.05), regardless of the system used. The rpm also directly correlated to the amount of time the bone remained at an elevated temperature.
From a heat generation standpoint, we conclude that preparing an implant site at 2500 rpm could decrease the risk of osseous damage, which may affect the initial healing of dental implants. This may decrease the devital zone adjacent to an implant after surgery and be most advantageous in immediate load application to dental implants.
The purpose of the present study was (1) to measure the primary stability of ITI implants placed in both jaws and determine the factors that affect the implant stability quotient (ISQ) determined by the resonance frequency method and (2) to monitor implant stability during the first 3 months of healing and evaluate any difference between immediately loaded (IL) implants and standard delayed loaded (DL) implants. The IL and DL groups consisted of 18 patients/63 implants and 18 patients/43 implants. IL implants were loaded after 2 days; DL implants were left to heal according to the one-stage procedure. The ISQ was recorded with an Osstell® apparatus (Integration Diagnostics AB, Gothenburg, Sweden) at implant placement, after 1, 2, 4, 6, 8, 10 and 12 weeks. Primary stability was affected by the jaw and the bone type. The ISQ was higher in the mandible (59.8±6.7) than the maxilla (55.0±6.8). The ISQ was significantly higher in type I bone (62.8±7.2) than in type III bone (56.0±7.8). The implant position, implant length, implant diameter and implant deepening (esthetic plus implants) did not affect primary stability. After 3 months, the gain in stability was higher in the mandible than in the maxilla. The influence of bone type was leveled off and bone quality did not affect implant stability. The resonance-frequency analysis method did not reveal any difference in implant stability between the IL and DL implants over the healing period. Implant stability remained constant or increased slightly during the first 4–6 weeks and then increased more markedly. One DL and IL implant failed; both were 8 mm long placed in type III bone. At the 1-year control, the survival rate of the IL and the DL implants was 98.4% and 97.7%, respectively. This study showed no difference in implant stability between the IL and DL procedures over the first 3 months. IL short-span bridges placed in the posterior region and full arch rehabilitation of the maxilla with ITI sandblasted-and-etched implants were highly predictable.
Les buts de l'étude présente étaient 1) de mesurer la stabilité primaire d'implants ITI placés dans les deux maxillaires et de déterminer les facteurs qui affectaient le quotient de stabilité implantaire (ISQ) déterminé par la méthode de fréquence de résonnance, 2) d'enregistrer la stabilité implantaire durant les trois premiers mois de guérison et d'évaluer les différences entre les implants immédiatement mis en charge (IL) et les implants avec charge retardée (DL). Les groupes IL et DL comprenaient respectivement 18 patients/63 implants et 18 patients/43 implants. Les implants IL ont été mis en charge après deux jours et les DL ont eu un temps de guérison sans charge suivant le processus standard. L'ISQ a été enregistréà l'aide d'un appareil Osstell® lors du placement de l'implant et après une, deux, quatre, six, huit, dix et douze semaines. La stabilité primaire était affectée par la mâchoire et le type d'os. L'ISQ était plus important dans la mandibule (60±7) que dans le maxillaire (55±7). L'ISQ était significativement plus important dans l'os de type I (63±7) que dans l'os type III (56±8). La position de l'implant, sa longueur, son diamètre et sa profondeur (les implants Esthetic plus) n'avaient pas d'influence sur la stabilité primaire. Après trois mois, le gain de stabilitéétait plus important dans la mandibule que dans le maxillaire. L'influence du type osseux était réduite et la qualité osseuse n'influençait pas la stabilité implantaire. La méthode RFA ne montrait aucune différence dans la stabilité implantaire entre les implants IL et DL durant la période de guérison. La stabilité implantaire restait constante ou augmentait légèrement durant les quatre à six semaines et augmentait ensuite de manière plus marquée. Un implant DL et un IL ont échoué, les deux avaient une longueur de 8 mm et étaient placés dans de l'os type III. Au contrôle après une année, les taux de survie des implants IL et DL étaient respectivement de 98,4 et 97,7%. Cette étude n'a montré aucune différence dans la stabilité implantaire entre les processus IL et DL après les premiers trois mois. Les bridges courts placés immédiatement dans la région postérieure et la réhabilitation de toute l'arche dentaire au niveau du maxillaire avec des implants ITI SLA étaient hautement prévisibles.
Das Ziel dieser Studie war: 1) die Primärstabilität von ITI-Implantaten in beiden Kiefern zu messen und die Faktoren zu suchen, die diesen Implantatstabilitätsquotienten (ISQ), bestimmt mittels Resonanzfrequenz-Analyse, beeinflussen; und 2) die Implantatstabilität während den ersten 3 Monaten der Heilphase longitudinal zu verfolgen und eventuelle Unterschiede zwischen sofort belasteten (IL) und gemäss Standardprotokoll belasteten Implantaten (DL) herauszufinden.
Die IL- und DL-Gruppen bestanden aus 18 Patienten/63 Implantaten und 18 Patienten/43 Implantaten. Die IL-Implantate belastete man nach 2 Tagen, die DL-Implantate liess man dem Standardvorgehen entsprechend einheilen. Mit einem Osstell®-Gerät bestimmte man nach der Implantation, sowie nach 1, 2, 4, 6, 8, 10 und 12 Wochen den ISQ.
Die Primärstbilität war durch den Knochentyp und die verschiedenen Kiefertypen beeinflusst. Im Unterkiefer war der ISQ höher (59.8±6.7) als im Oberkiefer (55.0±6.8). Ebenso war der ISQ im Knochentyp I signifikant höher (62.8±7.2) als im Knochentyp III (56±7.8). Implantatposition, -länge, -durchmesser und das vertiefte Setzen der Implantate (Esthetic plus) beeinflussten die Primärstabilität nicht. Nach 3 Monaten verbesserte sich die Stabilität im Unterkiefer mehr als im Oberkiefer. Wenn man den Einfluss des Knochentyps rechnerisch ausglich, hatte die Knochenqualität auf die Implantatstabilität keinen Einfluss. Die RFA-Methode zeigte zwischen den IL- und den DL-Implantaten in der Heilphase keine Unterschiede der Implantatstbilität. Die Implantate behielten ihre Stabilität oder zeigten in den ersten 4-6 Wochen eine leichte, später sogar eine markante Zunahme. Je ein DL- und ein IL-Implantat gingen verloren und wurden als Misserfolg gewertet. Beide waren 8 mm lang und in Typ III Knochen implantiert worden. In der Nachkontrolle nach einem Jahr betrug die Überlebensrate der IL-Implantate 98.4%, die der DL-Implantate 97.7%.
Diese Studie zeigte in den ersten 3 Monaten keine Unterschiede in der Implantatstabilität zwischen dem IL- und den DL-Protokoll auf. Die Prognose von sofortbelasteten Brücken mit kurzer Spannweite im posterioren Bereich und den ganzen Bogen umspannende Brücken im Oberkiefer mit ITI SLA-Implantaten konnten mit hoher Sicherheit vorausgesagt werden.
El propósito del presente estudio fue, (1) medir la estabilidad primaria de los implantes ITI colocados en ambos maxilares y determinar los factores que afectan al cociente de estabilidad primaria (ISQ) determinado por un método de frecuencia de resonancia, (2) monitorizar la estabilidad del implante durante los 3 primeros meses de cicatrización y evaluar cualquier diferencia entre implantes de carga inmediata (IL) e implantes estándar de carga diferida (DL).
Los grupos IL y DL consistieron de 18 pacientes/63 implantes y 18 pacientes/43 implantes. Los implantes IL se cargaron a los 2 días, los implantes DL se dejaron cicatrizar de acuerdo con el procedimiento de 1 fase. Se recogió el ISQ con un aparato Osstell® al colocar el implante, tras 1, 2, 4, 6, 8, 10 12 semanas.
La estabilidad primaria se afectó por el maxilar y el tipo de hueso. El ISQ fue mas alto en la mandíbula (57.8±6.7) que en el maxilar (55.0±6.8). El ISQ fue significativamente mas alto en el hueso tipo I (62.8±7.2) que en el hueso tipo III (56.0±7.8). La posición del implante, la longitud del implante, el diámetro del implante y la profundidad del implante (implantes Esthetic plus) no afectaron a la estabilidad primaria. Despues de 3, la ganancia de estabilidad fue mayor en la mandíbula que en el maxilar. La influencia del tipo de hueso se niveló y la calidad de hueso no afectó a la estabilidad implantaria. El método RFA no reveló ninguna diferencia en la estabilidad implantaria entre los implantes IL y DL a lo largo del periodo de cicatrización. La estabilidad de los implantes permaneció constante o se incrementó ligeramente durante las primeras 4 a 6 semanas y después aumentó mas marcadamente. Un implante DL y otro IL fracasaron, ambos de 8 mm de longitud colocados en hueso tipo III. En el control de 1 año, el índice de supervivencia de los implantes IL y DL fue del 98.4 y 97.7% respectivamente.
Este estudio no mostró diferencias en la estabilidad implantaria entre los procedimientos IL y DL a lo largo de los 3 primeros meses. Los puentes cortos cargados inmediatamente colocados en la región posterior y las rehabilitaciones de toda la arcada del maxilar con implantes ITI SLA fueron altamente predecibles.
The purpose of the present clinical study was (1) to evaluate the Osstell as a diagnostic tool capable of differentiating between stable and mobile ITI implants, (2) to evaluate a cut-off threshold implant stability quotient (ISQ) value obtained at implant placement (ISQitv) that might be predictive of osseointegration, (3) to compare the predictive ISQitv of immediately loaded (IL) implants and implants loaded after 3 months (DL). Two patient groups were enrolled, 18 patients received 63 IL implants and 18 patients were treated with 43 DL implants. The ISQ was recorded at implant placement, after 1, 2, 4, 6, 8, 10 and 12 weeks. All implants passed the 1-year loading control. Two implants failed, one DL implant with ISQ at placement (ISQi) of 48 and one IL implant with ISQi of 53. The resonance-frequency analysis (RFA) method was not a reliable diagnostic tool to identify mobile implants. However, implant stability could be reliably determined for implants displaying an ISQ> or =47. After 1 year of loading, all DL implants with an ISQi> or =49 and all IL implants with an ISQi> or =54 achieved and maintained osseointegration. By the end of 3 months, implants with ISQi<60 had an increase of stability. Implants with ISQi 60-69 had their stability decrease during 8 weeks before returning to their initial values. Implants with ISQ>69 had their stability decrease during the first 4 weeks before remaining stable. Although preliminary, these data might orient the practitioner to choose among various loading protocols and to selectively monitor implants during the healing phase.
Tissue formation at the implant interface is known to be sensitive to mechanical stimuli. The aim of the study was to compare the bone formation around immediately loaded versus unloaded implants in two different implant macro-designs.
A repeated sampling bone chamber with a central implant was installed in the tibia of 10 rabbits. Highly controlled loading experiments were designed for a cylindrical (CL) and screw-shaped (SL) implant, while the unloaded screw-shaped (SU) implant served as a control. An F-statistic model with alpha=5% determined statistical significance.
A significantly higher bone area fraction was observed for SL compared with SU (p<0.0001). The mineralized bone fraction was the highest for SL and significantly different from SU (p<0.0001). The chance that osteoid- and bone-to-implant contact occurred was the highest for SL and significantly different from SU (p<0.0001), but not from CL. When bone-to-implant contact was observed, a loading (SL versus SU: p=0.0049) as well as an implant geometry effect (SL versus CL: p=0.01) was found, in favour of the SL condition.
Well-controlled immediate implant loading accelerates tissue mineralization at the interface. Adequate bone stimulation via mechanical coupling may account for the larger bone response around the screw-type implant compared with the cylindrical implant.
Implant stability measurement of delayed and immediately loaded implants during healing.
- Bischof M.
- Nedir R.
- Szmukler-Moncler S.
Implant stability measurement of delayed and immediately loaded implants during healing
- Bischof