Tooth-size discrepancy: A comparison between manual and digital methods

Abstract

IntroductionTechnological advances in Dentistry have emerged primarily in the area of diagnostic tools. One example is the 3D scanner, which can transform plaster models into three-dimensional digital models.ObjectiveThis study aimed to assess the reliability of tooth size-arch length discrepancy analysis measurements performed on three-dimensional digital models, and compare these measurements with those obtained from plaster models.Material and MethodsTo this end, plaster models of lower dental arches and their corresponding three-dimensional digital models acquired with a 3Shape R700T scanner were used. All of them had lower permanent dentition. Four different tooth size-arch length discrepancy calculations were performed on each model, two of which by manual methods using calipers and brass wire, and two by digital methods using linear measurements and parabolas.ResultsData were statistically assessed using Friedman test and no statistically significant differences were found between the two methods (P > 0.05), except for values found by the linear digital method which revealed a slight, non-significant statistical difference.ConclusionsBased on the results, it is reasonable to assert that any of these resources used by orthodontists to clinically assess tooth size-arch length discrepancy can be considered reliable.

Reliability of measurements made on scanned cast models using the 3Shape R700 scanner

“…Correia et al 31 used the same scanner model as this research and compared the tooth-size discrepancy in birpublications.org/dmfr plaster models and digital models and concluded that there was no statistically significant difference. They carried out interproximal tooth measures and measures covering the curvature of models to obtain tooth-size discrepancy, so we concluded that the scan performed by R700 3Shape scanner is faithful also in interproximal and curvature areas.…”

3D Scanning, Imaging, and Printing in Orthodontics

“…Impressions, models, or bite registrations are positioned inside a chamber platform which is automatically rotated and inclined during scanning, ensuring complete multiple angle coverage of the model's geometry. The laser light is projected onto the object, and the cameras acquire its mirror image from the surface [47]. Upon scanning completion, a rendered stereolithographic model is created and plaster models, impressions, and bite registration can be discarded, eliminating the need for storage.…”

“…Ortho Insight 3D™ (Motion View Software, LLC, Chattanooga TN) was introduced in 2012, offering a high-resolution, robotic scan with an accuracy of 40-200 microns ( Figure 11). The automated laser scanner is designed to capture full arch impressions, plaster models, and bite registrations, and create 3D digital models [47]. A single cast scan and virtual model reconstruction can be completed in approximately 5 to 7 minutes.…”

3D Orthodontics - from Verne to Shaw

“…At first blush, the reliability of CT scans was successfully proved 12 Subsequently, images acquired by means of dental cast scanning proved perfectly feasible for clinical and scientific use 34 Scientific results also confirm the reliability of 3D face scans acquired with scanners or by means of stereophotogrammetry 5…”