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Objectives
The aim of this study was to compare the accuracy of dental implant impressions obtained by a combination of different impression techniques and viscosities of polyvinyl siloxane (PVS).
Materials and Methods
Four parallel fixtures were placed between mental foramina in a master model of lower dental arch. Three different viscosities (pu...
Context in source publication
Context 1
... first, the three scanned holes (tripoding) on the master arch were used to fabricate a metal model (holder) to hold the master arch or cast in the same position on the digitizer (Fig. 2). After the master arches and casts were mounted on the digitizer, different angulations were measured using digitizer probes (Trace Cut version 23; Renishaw Company, New Mills, UK) with the accuracy of 1µm. In the digitizer, analogues were coded 1 to 4, and then, a horizontal line was drawn in the same position as the reference line on ...
Citations
... A higher percentage of acceptable impressions (good or fair) was recorded using the dual phase than the monophase technique, with a statistically significant prediction that the dual viscosity technique was less likely to result in poor-quality impressions. Ghahremanloo et al. [27] in a study to compare the accuracy of dental implant impressions obtained by a combination of different impression techniques and viscosities of polyvinyl siloxane established that the monophase technique had a high incidence of voids and tears. However, while the monophase technique was more likely to result in poor-quality impressions in comparison to the dual viscosity technique, the difference was not statistically significant. ...
... However, while the monophase technique was more likely to result in poor-quality impressions in comparison to the dual viscosity technique, the difference was not statistically significant. The monophase technique has been found to result in a higher incidence of voids and tears even in custom trays, often attributed to failure to syringe the material properly over critical areas [22,27]. ...
Background: Good quality dental impressions free of air bubbles, voids, steps, drags, streaks and tears are a pre-requisite for the fabrication of well-fitting fixed dental prostheses (FDP). The quality of impressions is dependent on clinician and material factors.
Aim: To evaluate factors that influence the quality of final impressions for FDP in Nairobi, Kenya.
Methods: In this cross-sectional study, 234 impressions received by five dental laboratories were analyzed. The study collected information on the type of tray, impression material, technique, type of prostheses, and clinically detectable errors, including voids, inadequate material at margins, tears, steps, drags, and streaks. Impression quality was the outcome assessed as good, fair, or poor by two investigators. The independent variables influencing impression quality included clinician specialty, experience, impression material, technique, and tray type.
Results: Inter-rater agreement was 96.8% (p<0.001). Clinician experience ranged between 1-45yrs, median 13.5yrs and mean 8.39±11.96yrs. The majority were GPs, 80.8% while restorative dentists were 11.5% and other specialists, 7.7%. Most impressions were non-aqueous elastomers, 97.9% employing dual-viscosity technique, 75.6%. Impression trays included stock metal, 60.3%, stock plastic, 34.2%, and custom, 5.5%. Impression quality was good, 24.8%, fair, 37.2% or poor, 38.0%. Cumulatively, 74.5% impressions had bubbles/voids, 53.0% tears and 43.2% poor margins. Clarity of margins was associated with clinician specialty, (Fisher’s exact=9.372, p=0.047), and impression technique with impression quality, (Pearson’s ?2 = 6.385, p=0.041). Compared to restorative specialists, estimated odds of other specialists producing poor margins was 5.71, 95%CI 1.55,21.06, Wald ?2=5.24, p=0.009 while for GPs, the estimated odds was 2.19, 95%CI 0.88, 5.43, Wald ?2 = 2.86, p=0.09. Compared to dual viscosity, estimated odds of monophase giving a poor-quality impression was 1.52, 95%CI 0.83,2.78, Wald ?2 = 1.52, p=0.18.
Conclusion: Most impressions were good or fair hence acceptable. Quality of impressions was influenced by clinician specialty and impression technique.
... However, one major disadvantage of a putty silicone impression material is its poor ability to record fine surface detail. This is attributed to its high filler content, which leads to high viscosity and low flowability, thus hindering its ability to capture fine details (Ghahremanloo et al., 2017). Although this can be overcome by the application of a wash technique with a light body silicone impression, either in a onestep or two-step technique, this is seemingly technique sensitive and not cost effective. ...
The surface detail reproducibility of conventional putty impressions is hindered by high viscosity and low flowability. In the plastic industry, injection moulding application utilizes an influx of pressure to achieve better flowability. Leveraging this concept, this technical report investigated the impact of pressure on surface detail reproducibility and structural homogeneity, featuring the pressurised putty technique.Surface detail reproducibility and structural homogeneity of three techniques (non-pressurised, putty & light body wash and pressurised)were visually assessed and differences in surface detail reproducibility were observed among all techniques. Whilst a pressurised clear-based putty index presented a more uniform glassy finish. The outlined technique suggests a simplistic and cost-effective way of improving a putty index, which may benefit many clinicians in terms of prosthodontic success
... This study used both medium viscosity (monophase) and heavy+light viscosity materials; the rationale for the use of high viscosity phases is to achieve a stiffer impression to better stabilize the transfer copings. However, viscous elastomers have a limited ability to replicate fine details. 52 The difficulty of the heavy materials to completely penetrate the retentive grooves of the impression transfer copings, failing to completely embrace and stabilize them in spite of the injected light phase, could be an issue if a technique without splinting is used, possibly explaining the relatively low accuracy and precision recorded in HIH+L-ns in comparison with medium body HIM-ns group. ...
Statement of problem
New polyvinyl siloxane (PVS) materials with enhanced properties have been developed to improve and facilitate implant impression techniques. However, studies on their accuracy are lacking.
Purpose
The purpose of this in vitro study was to determine the accuracy and precision of implant impressions made with some recently introduced materials on a simulated patient requiring an all-on-4 implant-supported prosthesis. Well-established polyether materials were also evaluated as a comparison. The variables considered were material type, consistency, splinting or not splinting techniques, and implant angulation.
Material and methods
A reference master model was made by inserting 4 implants at angles of 0, 5, and 10 degrees. Eighty impressions were made at 37 °C in wet conditions by using a standardized technique. Eight groups (n=10) were created using monophasic, single-viscosity materials (Hydrorise Implant Medium, HIM-ns; Hydrorise Implant Medium, HIM; Honigum Mono, HM; Impregum, IMP), and 2-viscosity materials (Hydrorise Implant Heavy+Light-ns, HIH+L-ns; Hydrorise Implant Heavy+Light, HIH+L; Honigum Heavy+Light, HH+L; and Permadyne and Garant [Heavy+Light, PeH+L]). Hydrorise materials were used with splinting and not splinting (ns) techniques. The reference points located on the connecting platforms of the transfer copings (TCP) were compared with the same points on the implant connecting platforms (ICP) located in the reference model. The accuracy and precision of the impressions were determined as linear 3D errors and standard deviation between each TCP-ICP couple by using an optical coordinate measuring machine (OCMM).
Results
PVS materials were generally better than polyether materials, with Hydrorise materials (HIM and HIH+L) showing significantly better accuracy and precision (30.9 ±14.4 μm and 28.7 ±15.5 μm, respectively) than IMP and PeH+L polyethers (44.2 ±16 μm and 43.8 ±17.6 μm, respectively; P<.001). Honigum materials were statistically similar to Hydrorise materials (P=.765). The values shown by Hydrorise nonsplinted groups (HIH+L-ns and HIM-ns) were not statistically different from those of the splinted polyether impressions (P=.386). The viscosities (monophasic or heavy+light) had no effect on accuracy, but monophasic material positively influenced precision (HIM and HIH+L, P=.001). No correlation was found between implant angulation and accuracy (multilevel analysis and Kendall rank correlation coefficient=-0.065; P=.133).
Conclusions
Recently introduced materials designed for implant impressions showed significantly higher accuracy and precision; even with the unfavorable nonsplinting technique, the new materials performed similarly to, or better than, polyether materials. Although the transfer coping splinting technique generally improved the accuracy and precision of Hydrorise materials, the effect was significant only within HIH+L groups.
... PVS impression materials can be used in several techniques in accordance with the manufacturer's recommendations (6), taking into account their viscositi-DOI: 10 (3). The aim of this study was to evaluate the impression quality and clinical success of two PVS impression materials by using the dual-viscosity one-step impression technique and the putty-wash two-step impression technique. ...
Background: This study was to evaluate the impression quality and clinical success of 2 Polyvinyl siloxane (PVS) impression materials by using dual-viscosity 1-step impression technique and the putty-wash two-step impression technique.
Methods: In this study, Variotime (Heraeus, Hanau, Germany) and a novel silicone Spirias (Imicryl, Konya, Turkey) were selected as PVS impression materials. A total of 40 samples were divided into groups according to the impression technique. Three possible categories were established to rate the impression quality. The impression was examined using a laboratory microscope (Opmi Pico, Zeiss) and lenses with 2X to 6X magnification for the presence or absence of bubbles or voids and the complete reproduction of the preparation finish line. A spreadsheet (Excel v2016; Microsoft Corp) was used for processing statistical data. Results of the analysis were calculated as mean and frequency.
Results: In the impressions taken with Variotime, the percentage of the successful impression is 95% (Criteria I - II). Only one impression was found unacceptable (criteria III). In impressions with Spirias, the percentage of successful impressions is 100% (Criteria I - II). No-impression was found unacceptable (criterion III).
Conclusion: The quality of impressions of both brands Polyvinyl siloxane impression materials revealed a high rate (97.5%) For more precise results, many new studies were needed on different Polyvinyl siloxane impression materials.
... Although their findings showed that polyether, PVS, and vinyl siloxanether have no marked effect on the precession of impressions with parallel implants, still PVS showed better results. Yet, there were studies that consider VSE as the material of choice when the impression is to be made [35,36]. ...
... Although their findings showed that polyether, PVS, and vinyl siloxanether have no marked effect on the precession of impressions with parallel implants, still PVS showed better results. Yet, there were studies that consider VSE as the material of choice when the impression is to be made [35,36]. ...
... For the assessment of linear and angular distances between implants, reference models and test models were measured with coordinate measuring machines (CMM) Alikhasi, Siadat, Beyabanaki et al., 2015;Alikhasi, Siadat, & Rahimian, 2015;BalaMurugan & Manimaran, 2013;Bergin et al., 2013;Beyabanaki et al., 2015;Buzayan et al., 2013;Di Fiore et al., 2015;Ebadian et al., 2015;Ehsani et al., 2013;Geramipanah et al., 2015;Ghahremanloo et al., 2017;Gupta et al., 2017;Heidari et al., 2016;Martínez-Rus et al., 2013;Mpikos et al., 2012;Nakhaei et al., 2015;Ng et al., 2014;Rashidan et al., 2012;Selvaraj et al., 2016;Shankar et al., 2016;Siadat et al., 2016;Tsagkalidis et al., 2015;Vojdani et al., 2015;Wegner et al., 2013). Other authors used microscopes (Akalin et al., 2013;Aldosari, 2014;Aldosari et al., 2015;Chang et al., 2012;Ghanem et al., 2015;Haghi et al., 2017;Ibrahim & Ghuneim, 2013), digital micrometers (Al Quran et al., 2012;Tarib et al., 2012), a profile projector (Vigolo et al., 2014) or a laser measuring machine (Eliasson & Ortorp, 2012) to measure implant positions in conventional stone casts and compare them between reference and test models. ...
... implant impressions were performed with the open tray method (Akalin et al., 2013; Aldosari, 2014; Aldosari et al., 2015; Amin et al., 2016; de Avila, de Matos Moraes, Castanharo, Del'Acqua, & de Assis Mollo, 2014;Bergin et al., 2013;Beyabanaki, Shamshiri, Alikhasi, & Monzavi, 2015;Buzayan, Baig, & Yunus, 2013;Di Fiore et al., 2015;Ehsani et al., 2013;Geramipanah, Sahebi, Davari, Hajimahmoudi, & Rakhshan, 2015;Ghahremanloo et al., 2017;Ghanem, Nassani, Baroudi, & Abdel Fattah, 2015;Gupta et al., 2017;Heidari et al., 2016;Lin et al., 2015;Marotti et al., 2014;Ongül et al., 2012;Ono et al., 2013;Papaspyridakos et al., 2012;Perez-Davidi et al., 2016;Pozzi et al., 2013;Pujari, Garg, & Prithviraj, 2014;Selvaraj, Dorairaj, Mohan & Simon, 2016;Vigolo, Mutinelli, Fonzi & Stellini, 2014;Vojdani, Torabi, & Ansarifard, 2015;Zen et al., 2015), the closed tray method(Abdel-Azim et al., 2014;Calesini et al., 2014;Del'acqua, de Avila, Amaral, Pinelli, & de Assis Mollo, 2012;Gökçen-Rohlig et al., 2014;Ibrahim, Fouad, Elewa, & Mustafa, 2014;Ibrahim & Ghuneim, 2013;Karl et al., 2012;Lee et al., 2015;Reddy, Prasad, Vakil, Jain, & Chowdhary, 2013) or both the open and closed tray methods for comparison of the accuracy (Al Quran et al., 2012; Alikhasi, Siadat, Beyabanaki, & Kharazifard, 2015; Alikhasi, Siadat, & Rahimian, 2015; de Avila, Barros, Del'Acqua, Castanharo, & Mollo Fde, 2013; BalaMurugan & Manimaran, 2013; Chang, Vahidi, Bae, & Lim, 2012; Haghi, Shiehzadeh, Nakhaei, Ahrary, & Sabzevari, 2017; Hazboun, 2013; Howell et al., 2013; Karl & Palarie, 2014; Mpikos et al., 2012; Nakhaei, Madani, Moraditalab, & Haghi, 2015; Ng et al., 2014; Pera et al., 2016; Rutkunas, Sveikata, & Savickas, 2012; Sabouhi et al., 2015, 2016; Shankar et al., 2016; Shim et al., 2015; Siadat et al., 2016). Two studies did not use trays and compared stress induced by splinting two impression posts on dental implants with different splinting materials and techniques to each other (Lopes-Júnior, de Lima Lucas, Gomide, & Gomes, 2013a,b). ...
... Sixteen studies compared any combination of the aforementioned impression materials(Akalin et al., 2013;Alikhasi, Siadat, Beyabanaki et al., 2015;Alikhasi, Siadat, & Rahimian, 2015;Buzayan et al., 2013;Chang et al., 2012;Ebadian, Rismanchian, Dastgheib, & Bajoghli, 2015;Gökçen-Rohlig et al., 2014;Gupta et al., 2017;Haghi et al., 2017;Karl & Palarie, 2014;Kurtulmus-Yilmaz et al., 2014;Pujari et al., 2014;Reddy et al., 2013;Rutkunas et al., 2012;Shankar et al., 2016;Vojdani et al., 2015;Wegner, Weskott, Zenginel, Rehmann, & Woestmann, 2013).Splinting of impression copings was studied and compared with nonsplinting of impression copings in numerous studies. Thirty-two studies used nonsplinted impression copings(Akalin et al., 2013;Aldosari, 2014;Aldosari et al., 2015;Alikhasi et al., 2013;Alikhasi, Siadat, Beyabanaki et al., 2015;Alikhasi, Siadat, & Rahimian, 2015;BalaMurugan & Manimaran, 2013;Calesini et al., 2014;Ebadian et al., 2015;Ehsani et al., 2013;Eliasson & Ortorp, 2012;Geramipanah et al., 2015;Ghahremanloo et al., 2017;Gökçen-Rohlig et al., 2014;Haghi et al., 2017;Howell et al., 2013;Ibrahim et al., 2014;Karl & Palarie, 2014;Karl et al., 2012;Lee et al., 2015;Lin et al., 2015;Marotti et al., 2014;Mpikos et al., 2012;Nakhaei et al., 2015; Ng et al., 2014; Rashidan et al., 2012; Reddy et al., 2013; Sabouhi et al., TA B L E 6 Analysis of linear and 3D surface deviations (μm) measured for conventional and digital impressions ...
Aim
This systematic review and meta‐analysis were conducted to assess and compare the accuracy of conventional and digital implant impressions. The review was registered on the PROSPERO register (registration number: CRD42016050730).
Material and Methods
A systematic literature search was conducted adhering to PRISMA guidelines to identify studies on implant impressions published between 2012 and 2017. Experimental and clinical studies at all levels of evidence published in peer‐reviewed journals were included, excluding expert opinions. Data extraction was performed along defined parameters for studied specimens, digital and conventional impression specifications and outcome assessment.
Results
Seventy‐nine studies were included for the systematic review, thereof 77 experimental studies, one RCT and one retrospective study. The study setting was in vitro for most of the included studies (75 studies) and in vivo for four studies. Accuracy of conventional impressions was examined in 59 studies, whereas digital impressions were examined in 11 studies. Nine studies compared the accuracy of conventional and digital implant impressions. Reported measurements for the accuracy include the following: (a) linear and angular deviations between reference models and test models fabricated with each impression technique; (b) three‐dimensional deviations between impression posts and scan bodies respectively; and (c) fit of implant‐supported frameworks, assessed by measuring marginal discrepancy along implant abutments.) Meta‐analysis was performed of 62 studies. The results of conventional and digital implant impressions exhibited high values for heterogeneity.
Conclusions
The available data for accuracy of digital and conventional implant impressions have a low evidence level and do not include sufficient data on in vivo application to derive clinical recommendations.
Background:
Making accurate impressions of dental implants and transferring their three-dimensional (3D) position to master casts is critical for the passive fit of prosthetic frameworks.
Objectives:
This study aimed to assess the effect of dental implant angulation on the dimensional accuracy of master casts.
Material and methods:
An acrylic model with 2 external hexagonal implants was used in this in vitro experimental study. The impressions of the model were made in 42 positions, with different angulation of the 2 implants, ranging from +15° to -15°, by means of the open-tray and closed-tray impression techniques, using a polyvinyl siloxane impression material. The spatial coordinates of the implants were measured on the X, Y and Z axes. The dimensional accuracy of the impressions made at different positions (parallel, convergent and divergent) and different angulation of the implants were determined. The data was analyzed using the one-way analysis of variance (ANOVA), Student's t test and Tukey's test.
Results:
Casts with the lowest accuracy were obtained when the 2 implants were divergent by 25° (R = 1.1336). However, the position of the 2 implants had no significant effect on the dimensional accuracy of the master casts. The error rate was 0.4181 in the open-tray technique and 0.5095 in the closed-tray technique, with no significant difference between them (p > 0.05). The angulation of the 2 implants had a significant effect on the dimensional accuracy of the master casts (p = 0.0001).
Conclusions:
Considering the significant effect of implant angulation in the range from +15° to -15° relative to the longitudinal axis on the dimensional accuracy of master casts, further studies are required to reach a final conclusion in this respect.
