This systematic review aimed to evaluate the efficiency and accuracy of digital impression techniques for implant-supported restorations, and to assess their economic feasibility. Two independent electronic database searches were conducted in the Pubmed/MedLine, Cochrane Library, and Lilacs databases complimented by a manual search, selecting relevant clinical and in vitro studies published between 1st January 2009 and 28st February 2019. All type of studies (in vivo and in vitro) were included in this systematic review. Twenty-seven studies (8 in vivo and 19 in vitro studies) fulfilled the inclusion criteria. No meta-analysis was performed due to a large heterogeneity of the study protocols. The passive fit of superstructures on dental implants presented similar results between digital and conventional impression techniques. The studies considered that several factors influence the accuracy of implant impression taking: distance and angulation between implants, depth of placement, type of scanner, scanning strategy, characteristics of scanbody, and operator experience. Regarding the economic viability of intraoral scanning systems, only one study reported any benefit in comparison with conventional techniques. Digital impressions of dental implants can be considered a viable alternative in cases of one or two contiguous dental implants. However, more studies are needed to evaluate the accuracy of digital techniques in full-arch implant-supported restorations. Key words:Intraoral scanner, dental implant, prosthesis, misfit, systematic review.

The aim of this study was to assess the long-term clinical behavior of straight implants in comparison with intentionally tilted dental implants (ITDI) supporting fixed restorations in partial or total edentulous arches, analyzing implant survival and success rates, complications, and marginal bone loss (MBL) after >5 years of function. An electronic search was conducted in five electronic databases (MEDLINE/Pubmed, Embase, Web of Science, Scopus, and Cochrane Central Register of Controlled Trials) supplemented by a manual search. The electronic and manual search identified 1853 articles, of which 8 articles were selected for analysis. Out of a total of 3987 dental implants, 2036 were axial dental implants and 1951 tilted. Similar results were found in implant survival or overall implant success rates. Moreover, no statistically significant differences were found in MBL (p = 0.369; MD 0.116 mm (−0.137; 0.369) 95% CI) The prosthodontic/biological complications reported in the articles were very diverse and irregularly distributed. This systematic review suggests that there is no difference between tilted compared with straight dental implants in the medium-long term (>5 years). However, further research is needed to generate long-term data and confirm the present review’s findings.

Background and objectives: The main purpose of this study was to evaluate the survival and success rates of dental implants with a double acid-etched surface treatment with evaluation times up to 10 years post-loading. Materials and Methods: This study was conducted at a hospital oral surgery and implantology unit. It included 111 dental implants with a double acid-etched surface. Three groups were created: Group 1 (1–3 years loading), Group 2 (3–5 years loading), and Group 3 (over 5 years loading). Probing depth, resonance frequency analysis (ISQ value), and marginal bone loss were evaluated. Results: The data obtained underwent statistical analysis. Overall, 78 patients were included in the study, who received, in total, 111 dental implants, all replacing single teeth. Mean probing depth was 3.03 mm and mean ISQ was 65.54. Regarding marginal bone loss, in Group 1, 67.6% of implants did not undergo any thread loss, in Group 2, 48.3%, and in Group 3, 59.6%; 59.10% of all implants did not present thread loss with a mean bone loss of 0.552 mm. The implant survival rate was 99.1%, and the success rate was 96.37%. Conclusions: Implants with a double acid-etched surface showed excellent success rates in terms of marginal bone loss, ISQ, and probing depth after up to 10 years of loading, making them a clinically predictable treatment option. Future studies are needed to compare this implant surface with other types in different restorative situations.

Printed cast models are becoming increasingly important in prosthodontics. The aim of this in vitro study was to evaluate the influence of print orientation and external shell thickness on the accuracy of stereolithography (SLA) master casts for fixed dental prostheses. Seventy-two maxillary hollow master casts were fabricated from a standard tessellation language (STL 0) reference file containing dental preparations. The casts were divided into six groups (n = 12 per group) according to internal shell thickness (2 mm and 4 mm) and print orientation (0°, 10°, and 20°). Discrepancies between STL 0 and the STL files of the printed casts were measured using the root mean square (RMS) error. Data were statistically analyzed using a one-way Kruskal–Wallis test to assess trueness, and precision was evaluated with the Levene test (α = 0.05). No statistically significant differences were found in any of the tested conditions. Print orientation and cast thickness did not influence the overall accuracy of SLA master casts for fixed dental prostheses.