This is an open access article under the terms of the Creat ive Commo ns Attri bution-NonCo mmercialLicense, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Objective To assess clinical and radiological performance of novel digital workflow integrating dynamic guided surgery, to streamline execution of implant placement, soft and bone tissue sculpturing, and immediate delivery of navigation guided complete‐arch prosthesis. Materials and Methods This proof of concept prospective single cohort study investigated 10 consecutive patients (three males, seven females; mean age 62.5 ± 8.9 years; range, 48–75) requiring at least one complete‐arch fixed dental prostheses (FDP) in both jaws, treated between January and August 2019. Primary outcomes were implant and prosthetic success rates, surgical and prosthetic complications. Secondary outcomes were marginal bone loss (MBL), implant stability quotient (ISQ), periodontal parameters (plaque and bleeding indexes). Results Sixty implants (32 NobelParallel TiUltra and 28 NobelActive TiUltra, Nobel Biocare) were placed and 14 complete‐arch FDPs immediately loaded (mean follow‐up 16.2 ± 1.7 months, 14–18). One implant failed and was immediately replaced. No other surgical or biological complications occurred, accounting for a cumulative success rate of 98.3%. No prosthetic complication occurred, leading to 100% prosthetic success rate. Mean ISQ at implant placement was 71 ± 2.8 (65–78). The mean MBL was −0.53 ± 0.28 mm (−0.22 to −1.12 mm). Plaque and bleeding scores were 14.4 ± 8.18 and 7.15 ± 4.4, respectively. Conclusion Within the limitations of this proof‐of‐concept dynamic navigation was effective to deliver in the planned coordinates both implants and prosthesis and guide bone and soft tissue sculpturing. Immediate loading of digitally prefabricated esthetically driven complete‐arch FDP was facilitated, resulting in high implant and prosthetic success rates. Clinical Significance The investigated digital workflow integrating dynamic navigation may overcome the difficulties related to immediate positioning and loading of digitally prefabricated complete‐arch FDP. The navigation guided soft and bone tissues sculpturing, associated to xenogeneic collagen matrix grafting, represented a predictable technique to achieve the digitally planned interface, reestablishing the mucosal dimension required for the protection of underlying bone while maintaining tissue health.

SUMMARYObjectives. The aim of the study was to assess the depth and quality of the post-space reading, using an IOS without scanpost, compared to a traditional silicon technique. Methods. Six extracted bicuspids were decoronated and endodontically treated. After having prepared the space for the posts, a structure in pink acrylic resin was created with two resin elements. At the center of the structure one sample was put at a time. Digital and traditional impressions were taken for each sample. Digital impressions were developed through the Computer-aided design (CAD) software in order to integrate the scanner results into a three-dimensional grid to make the measurements. A K-file was used to measure the length of the postspace of each sample obtained through the traditional silicon impression and subsequently the measurement results were reported on a millimeter gauge. Furthermore, an assessment of the width of the entrances of the post-spaces was carried out. Results. The mean reading depth discrepancy expressed in percentages (19.58%) indicates that the digital impression with current technologies fails to impress clearly the post-space. Standard deviation of the data expressed in percentage is 13.89, suggesting that the values were not similar to each other. In two cases the digital technique has achieved less than 10% difference compared to the traditional technique, but there have been also cases in which the variation in depth has reached almost 40%. The samples that showed the minor discrepancy between the two techniques expressed the widest post-space entrance. Conclusions. In this in vitro study, the application of the IOS for the post-space reading in order to deliver an anatomic post has been proven to be still not reliable, as there are still depth reading limitations for the narrow root channels. In fact, in this type of channels it is difficult to reach with the light beam of the IOS the deepest areas of the post-space, with a consequent incomplete post-space reading.

No abstract

The aim of this study was to systematically review the current scientific literature regarding the accuracy of fully guided flapless implant positioning for complete-arch rehabilitations in edentulous patients and to assess if there was any statistically significant correlation between linear deviation at shoulder point, at apex point and angular deviation. The electronic and manual literature search of clinical studies was carried out using specified indexing terms. A total of 13 studies were eligible for qualitative analysis and 277 edentulous patients were rehabilitated with 1556 implants patients by means of fully guided mucosa-supported template-assisted flapless surgery. Angular deviation was 3.42° (95% CI 2.82–4.03), linear deviation at shoulder point 1.23 mm (95% CI 0.97–1.49) and linear deviation at apex point 1.46 mm (95% CI 1.17–1.74). No statistically significant correlations were found between the linear and angular deviations. A statistically significant correlation was found between the two linear deviations (correlation coefficient 0.91) that can be summarized by the regression equation y = 0.03080 + 0.8254x. Computer-assisted flapless implant placement by means of mucosa-supported templates in complete arch restorations can be considered a reliable and predictable treatment choice despite the potential effects that flapless approach could bring to the overall treatment.