The effect of different intraoral scanners and conventional impression materials on the impression accuracy of single unit implants

Implant-based prosthetic restorations have become one of the first treatment options that come to mind in cases of partial and complete edentulism. The impression phase is one of the most important stages in producing a quality implant-supported prosthesis. It is not possible to produce a healthy prosthesis if a good impression is not taken and the position of the implants in the bone cannot be transferred correctly to the main model. The aim of our study is to compare the trueness and precision levels of various intraoral scanner technologies, which are rapidly developing today, and conventional impression materials that have been used successfully in dentistry for years, and as a result, to compare the accuracy of all scanners and impression materials. In our study, measurements were taken with 5 different intraoral scanners and 3 different conventional impression materials on the jaw model with a single implant in the molar region. STL (Standard Triangle Language) scan data obtained from the measurements taken was loaded into a reverse engineering software and superimposed one by one on the reference scan obtained from the model with an industrial optical scanner. The resulting deviation values were recorded. As the first step of the statistical analysis, the normality assumption was checked with the Shapiro Wilk test, and the homogeneity of variance was checked with the Levene test. One-Sample T test to examine the difference between a constant value and measurement averages in cases where the normality assumption is met; In cases where the assumption was not met, the Wilcoxon Sign Rank test was used. ANOVA test was used to compare the means of three or more independent groups with normal distribution, and the Kruskal Wallis test was applied in cases where the assumptions were not met. Post Hoc Bonferroni and Tamhane's T2 analyzes were used to determine the group or groups that made the difference. Analyzes were carried out in IBM SPSS 25 program. At the end of our study, it was found that CEREC Primescan showed the highest accuracy value. Among conventional impression materials, the highest accuracy value was determined in the polyether group.