The aim of this study was to evaluate the factors affecting intra-oral scanner accuracy by analyzing variation in measurements of a dental model according to scanning distance. A dental cast, including a prepared left mandibular first molar, was used. Rectangular frames measuring 20 × 30 mm with heights of 2.5, 5.0, and 7.5 mm were made. The model was scanned 10 times with a reference scanner to obtain the true value. Scanning was performed 10 times at four distances of 0, 2.5, 5.0, and 7.5 mm with the frame of each height using the following intra-oral scanners: TRIOS; CS 3500; and PlanScan. In the linear distance measurement method (2D), measurements were taken at five parameters using the Rapidform software. In the best-fit alignment method (3D), using the Geomagic Control X, the root mean square values of the two scan images were calculated. In the 2D comparison, the different from the reference value was the smallest at 2.5 and 5.0 mm. In the 3D comparison, 2.5 and 5.0 mm were the most accurate, and 0 mm was the least accurate among the four distances. To the best of our knowledge, this study was the first to evaluate the accuracy of scanning distances, and found a difference between the accuracy of the scanning distance and the accuracy of the scanner. Moreover, the results of this study indicated that the scanning distance was a variable affecting accuracy. Clin. Anat. 32:430-438, 2019.
Tooth wear is an unavoidable process associated with aging. Currently, virtual three-dimensional dental models are widely used and provide an advantage for studying tooth wear. However, there are no wear assessment parameters using virtual tooth models for the quantitative analysis of wear. Therefore, the aim of this study is to develop and evaluate quantitative wear measurement parameters. Ninety maxillary and mandibular dental casts were prepared and rendered as virtual three-dimensional models. For qualitative wear scoring, Hooper's new tooth wear index (NTWI) was used. For quantitative wear measurement, virtual vectors and occlusal planes were generated with reference points. Angles, height, and distance parameters were measured from reference points, vectors or planes. Intra- and interobserver reproducibility was determined for NTWI scoring and quantitative measurements. Quantitatively measurements for all parameters were subgrouped according to age groups and NTWI score groups. The mean and standard deviation were calculated for each group. One-way analysis of variance (ANOVA) test and the coefficients test were performed on the groups. Overall, intra- and interobserver reproducibility was good for both qualitative and quantitative measurement. In the ANOVA test, angle and height parameters showed significant differences between groups, whereas distance parameters did not. Similar results were observed in the coefficients test. However, plane heights and lingual side measurement parameters of the mandible are not recommended. In conclusion, this study indicates that all angle or height parameters of the maxilla and angle or vector height parameters of the buccal side of the mandible can be used as meaningful parameters in a quantitative wear study.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.