Comparison and reproducibility of three methods for maxillary digital dental model registration in open bite patients

Abstract

Objective: To compare and assess the reproducibility of 3 methods for registration of maxillary digital dental models in patients with anterior open bite. Settings and sample populationDigital dental models of 16 children with an anterior open bite in the mixed dentition were obtained before (T1) and after 12 months of treatment with bonded spurs (T2).Methods: Landmarks were placed on all T2 models and 3 registration methods (R1, R2 and R3) were independently performed by 2 observers. R1 was based on 10 landmarks placed on posterior teeth. R2 was based on 5 landmarks on the palate (2 anterior, 2 posterior and 1 central). R3 used regions of interest around the 5 palatal landmarks used in R2. The differences between the registration methods were calculated by comparing the mean differences and standard deviations between the corresponding x, y and z coordinates of 6 corresponding landmarks in the T2 registered models. Repeated measures analysis of variance followed by post-hoc Bonferroni tests were used for comparisons (P < .05). The agreement between methods and the intra and interobserver reproducibility were assessed with Bland-Altman tests and intraclass correlation coefficients (ICC).Results: Comparisons of R2 with R3 methods showed greater agreement, mean differences ≤0.50 mm for all landmarks, than comparisons of R1 with R2, and R1 with R3, mean differences >0.50 mm for most of the y and z coordinates (P < .05). The R1 and R3 methods presented excellent intra and interobserver reproducibility and R2 method had moderate interobserver reproducibility. Conclusions:Longitudinal assessments of open bite treatment using digital dental models could consider the posterior teeth and/or the palate as references. The R1 and R3 methods showed adequate reproducibility and yield different quantitative results. The choice will depend on the posterior teeth changes and dental models' characteristics.

Three-dimensional dentoalveolar changes in open bite treatment in mixed dentition, spurs/posterior build-ups versus spurs alone: 1-year follow-up randomized clinical trial

“…Vertical changes could be expected at the first rugae and incisive papilla in growing patients and these changes were related with positional changes of the maxillary incisors 23 , 24 . Therefore, superimposition methods excluding the most anterior region of the palate should be used, even more in open bite patients because the vertical positional changes in this area, with treatment, could affect the superimposition results 23 , 24 , 30 .…”

“…3 E,G). These methods have been previously assessed and showed adequate reproducibility 30 . TR superimposition showed the relative changes of the anterior teeth in relation to the posterior teeth and PR superimposition showed the relative changes of the anterior and posterior teeth in relation to the palate.…”

“…3 F,H). The differences in the amounts of displacements and inclinations of the incisors between the TR and PR methods could be expected because the methods used different structures for superimposition 30 .…”

“…Previously reported registration methods were performed: landmark-based registration on the posterior teeth (TR) and registration on the palate using regions of interest (PR) 30 . Assessment of the medio-lateral, antero-posterior, superior-inferior, and complete 3D displacements were included in this trial.…”