In vitro analysis of intraoral digital impression of inlay preparation according to tooth location and cavity type

Abstract

Purpose: This study aimed to evaluate the influence of tooth location and inlay cavity type on the accuracy of intraoral digital impressions. Methods: Class II inlay preparation was performed on anatomical models of the maxillary first molar (16) and mandibular first molar (46). Mesioocclusal and disto-occlusal cavities were prepared, such that the axial wall of the proximal box measured 1 mm or 2 mm in height. Thus, four types of inlay cavities were prepared in 16 and 46, respectively. Ten digital impressions of each cavity were obtained using Cerec Primescan (Sirona). Reference scans were obtained with a laboratory scanner (E3, 3Shape). All scan data were exported for comparative analysis of the three-dimensional models. Mean absolute deviation values were calculated to evaluate the trueness and precision of the digital models. Color-coded maps were used for the qualitative analysis of deviations. Results: The overall results showed that the trueness for 16 (10.43 ± 0.39 μm) was higher than that for 46 (12.42 ± 0.59 μm) (p < 0.05), while the precision was similar between 16 (3.08 ± 0.92 μm) and 46 (3.08 ± 0.76 μm). The cavity type affected the accuracy of the digital impressions. The highest deviation was observed in positive directions at the margins of the proximal boxes regardless of the cavity type. Conclusions: Tooth location and cavity type affected the accuracy of intraoral digital impressions. Positive deviations were observed at the margins of the proximal boxes.

Effect of Different Preparation Depths for an Inlay‐Retained Fixed Partial Denture on the Accuracy of Different Intraoral Scanners: An In Vitro Study

“…9 However, that study was concerned with the taper between opposing walls, while the present study was concerned with preparation depth. This was also not in agreement with a study by Kim et al, 41 who concluded that cavity width affects both trueness and precision of intraoral scans. In another study by Son et al, 42 they concluded that an increase in the distance between the inlay cavity and adjacent teeth had a favorable effect on precision and trueness of intraoral scans.…”

Effect of preparation type on the accuracy of different intraoral scanners: An in vitro study at different levels of accuracy evaluation

“…Today, IOS systems have the advantages of ease of use, ergonomic handling, quick scanning, and reliability. Several studies have confirmed the accuracy of IOS systems for multiple applications 1–8 . However, despite the abundance of studies on the accuracy of IOS systems, there is considerable disparity in their designs 9–12 .…”

“…The variations can be related to the scanning span, the number of units, scanned substrate material and design, and the condition of the scanned teeth 10 . One of the features that have not been fully investigated is the implication of tooth preparation type on the accuracy of IOS 1–3,9,13–15 . Variations in preparation types and designs, such as crown, onlay, and inlay, may interfere with the scanning process and the capturing of the preparation surface details 16–21 .…”

Effect of Scanned Area and Operator on the Accuracy of Dentate Arch Scans with a Single Implant

“…The use of a laboratory scanner to obtain the reference scans is a limitation. However, the accuracy of the applied laboratory scanner is high, and the application of laboratory scanners to obtain reference datasets has been recommended [ 38 , 39 , 40 , 41 ]. Future studies should be performed by using an industrial grade scanner for high-accuracy reference scans.…”