Abstract
Objective: The objective of this in vitro study was to investigate the effect of a novel 3D-printed AGD with titanium, PEEK and 3D-printed ISBs on the accuracy of intraoral scanning the edentulous mandibular arch.
Materials and Methods: A resin-based edentulous mandibular model with four implants was scanned using a laboratory scanner (E4, 3Shape) and an IOS system (Primescan, Dentsply Sirona). Six experimental groups, consisting of three types of ISBs (Titanium [Atlantis IO FLO-S, Dentsply Sirona], PEEK [53.107, DESS], and 3D-printed ISBs), with or without AGDs, were evaluated. Fifteen IOS scans were performed per group and were analysed using reference-based methods to assess trueness and precision of positional and angular measurements for each implant. Trueness was statistically analysed using three-way PERMANOVA with Bonferroni adjustments for post-hoc comparisons (α = 0.05), and precision was evaluated using Levene’s test (α = 0.05).
Results: Trueness was significantly influenced by ISB type, implant location, and AGD use. There was a trend of decreasing accuracy as the distance away from the reference-based origin increased. At the furthest ISB, the 3D deviation was statistically different for Titanium ISBs, with a mean of 183±93 μm and 29±47 μm for scans taken without and with AGDs, respectively. On the other hand, the accuracy of PEEK ISBs (105±70 μm vs 141±66 μm) and 3D-printed ISBs (229±148 μm vs 302±102 μm) showed no statistical differences without and with AGDs, respectively.
Conclusion: The effect of AGDs on accuracy interacted with ISB characteristics. The inclusion of AGDs enhanced scanning accuracy for Titanium ISBs but had no significant improvement on PEEK and 3D-printed scanbodies. The use of 3D-printed scanbodies is not recommended due to their clinically unacceptable accuracy.