3D palatal superimposition in adolescent orthodontic patients treated without extractions: method validation.

OBJECTIVES

This study investigated the morphological stability, trueness and precision of four palatal areas (A: medial 2/3 of third ruga and 5 mm posteriorly; B: A + additional 5 mm posteriorly; C: A + additional 6 mm wide stripe on midpalatal suture; D: almost whole palate) used for 3D superimposition of serial maxillary dental models in growing orthodontic patients treated without extractions.

MATERIALS AND METHODS

A retrospective sample of 25 growing patients with pre- (T0) and post- (T1) treatment 3D dental models was used. Morphological stability was assessed using color-coded distance maps generated from superimposed T0 and T1 models. Trueness was determined by measuring the Mean Absolute Distances (MAD) within Area A between T0 and T1 models after superimposition. Precision was evaluated through the assessment of T0-T1 changes in three preselected teeth.

RESULTS

Treatment and growth modified the palatal surface morphology at the 0.5 mm level. Trueness remained below 0.3 mm in most cases for Areas A, B, and C, with a reduced level observed for Area D. The precision outcome was significantly affected with respect to tooth torque and rotations. Area D showed the best precision, followed by B, C, and A. Area B showed the best agreement to Area C. The overall assessment favored Area B.

CONCLUSION

Considering overall performance, area B is recommended as the area of choice for superimposing pre-to post-orthodontic treatment maxillary dental models of growing individuals treated without extractions.

CLINICAL RELEVANCE

The suggested palatal superimposition method is broadly applicable and ensures reliable assessment of morphological changes through the superimposition of serial maxillary dental models.