Influence of implant scanbody material and operator on scanning fluency and polygonal mesh numbers of digital impression: an in vitro study

The purpose of this study is to evaluate the influence of implant scanbody (ISB) material and operator on scanning fluency and polygonal mesh numbers of a confocal microscopy intraoral scanning (IOS). An edentulous maxillary master model with 6 implant analogues was assembled. Thereafter 3 ISBs featured with same geometry but different materials (polyetheretherketone (PK), titanium (T) and PK with a titanium base (PKT)) were produce and scanned according to a randomized sequence by three different operators. The confocal microscopy IOS resulted in 45 STL test files that were processed to a dedicate software to obtain the request data. The overall analysis of fluency (imm/sec) showed the following results: mean 11.997 imm/sec, SD 2.355. The multivariate analysis showed statistical significance of material (p<.0001) and operator (p<.0001) influence. The univariate analysis referred to polygonal mesh numbers expressed the following results: mean 30327.8, SD 2432.5. The multivariate analysis stressed how there is a related effect to materials (p<.0001) and operator (p=0.0205). PKT represented the material with the best results for both. Analyzing the overall distribution histogram for scanning fluency, the IOS device seems to work with higher frequency at level of 13 imm/sec. The distribution of the measurements in the reference histograms showed an effect related to both variables referring to scanning fluency as well as to polygonal mesh numbers. Operator can be considered as a random effect; regarding the materials, the difference between PKT and PK can be related to the different base material. The dissimilar optical properties of T justify the different behavior.