A new technique for testing accuracy and sensitivity of digital bite registration: A prospective comparative study

Intraoral scanners (IOS) use certain algorithms to provide articulations of the upper and lower digital models. The study was primarily designed to test the accuracy and sensitivity of these virtual articulations. The secondary objective was to compare virtual occlusal recording to traditional methods.

A total of one hundred and sixty bite registrations (BR) were obtained from forty class I patients using four different methods. Samples were divided into four groups: Group 1: BR from wax, Group 2: BR from C type silicone, Group 3: BR from A type silicone, Group 4: Virtual BR created with Appliance Designer (Copenhagen, Denmark) software from the automatically articulated digital models. Traditional BRs of the first three groups were scanned and digitalized with IOS (3Shape TRIOS). Group 3 BRs were then taken as a reference and each of the BRs in Group 1, Group 2, and Group 4 were separately superimposed using Geomagic Control X. Numeric data such as Mpos (mean of positive deviations), Mneg (Mean of negative deviations), ITA (In total area), OTA (Out total area) were used in the comparison.

The values for OTA were: Group 1:57.0%, Group 2:28.4%, and Group 4:22.3% respectively. That meant a general deviation in thickness on nearly all of the occlusal registration surfaces. The Mpos values representing the discrepancy in thickness were Group 1:185.5μ, Group 2:82.7μ, and Group 4:72.2μ. The surface deviation of Group 1 was significantly different from the other groups (P<0.01).

Virtual bite registrations could safely be used as an alternative to conventional BRs. The performance of wax as a bite registration material was far behind other methods.