Int J Comput Dent 20 (2017), No. 4 15. Dec. 2017
Int J Comput Dent 20 (2017), No. 4 (15.12.2017)
Page 377-392, PubMed:29292412, Language: English/German
Assessment of residual coronal tooth structure postendodontic cavity preparation using digital dental impressions and micro-computed tomography
Al-Nuaimi, Nassr / Patel, Shanon / Foschi, Federico / Mannocci, Francesco / Austin, Rupert S.
Objectives: To evaluate the in vitro accuracy of digital impressions for three-dimensional (3D) volumetric measurement of residual coronal tooth structure postendodontic cavity preparation, with reference to micro-computed tomography (μCT).
Methods: Quantification of the accuracy and precision of the intraoral digital scanner (3M True Definition Scanner - IOS) was performed using a metrology gauge block and a profilometric calibration model. Thirty-four human extracted molars with endodontic access cavities were scanned using both intraoral scanning (test scanner) in high-resolution mode, and µCT (reference scanner: GE Locus SP μCT scanner) in high- (HiResCT) and low- (LoResCT) resolution modes. Comparisons of volumetric accuracy and 3D profilometric deviations were performed using surface metrology software. One-way repeated measures analysis of variance (ANOVA), in combination with the Bonferroni post hoc test, was implemented to compare the differences in volume measurements between scanning methods.
Results: Digital scanning revealed smaller volume measurements by 1.36% and 0.68% compared to HiResCT and LoResCT, respectively. There was a statistically significant difference in the volumetric measurements obtained from the IOS scanner and both HiResCT and LoResCT scans (P < 0.001). Analysis of the mean 3D profilometric deviations revealed that the IOS displayed greater surface deviation (± 27/33 μm) vs HiResCT and LoResCT (± 16/32 μm).
Conclusions: Although volumetric measurements of endodontically accessed teeth were up to 1.36% smaller in comparison to µCT, the digital scanner was able to reliably measure the extra- and intracoronal aspect of the endodontically accessed tooth.
Keywords: intraoral scanner, micro-computed tomography, endodontic cavity preparation, residual coronal tooth structure, volumetric, metrology