Retrospective investigation of the 3D effects of the Carriere Motion 3D appliance using model and cephalometric superimposition

Objectives: Carriere Motion 3D™ appliance (CMA) represents a method for molar distalization and correction of class II malocclusion. The aim was to investigate the 3D effects of the CMA by superimposing digital models and cephalometric X-rays.

Materials and methods: We retrospectively examined 16 patients treated with CMA in combination with class II elastics. We compared digitized models and cephalometric X-rays of records taken before therapy and after the removal of CMA. The records were superimposed to assess the skeletal and dentoalveolar changes. The results of the cephalometric X-ray analysis were compared to an untreated age- and gender-matched sample.

Results: Class II occlusion was corrected after 11.85 ± 4.70 months by 3.45 ± 2.33 mm. The average distalization of the upper first molars was 0.96 ± 0.80 mm. The analysis of the cephalometric X-rays confirmed a distalization of the upper first molars with distal tipping and revealed a mesialization of the lower first molars of 1.91 ± 1.72 mm. Importantly, CMA resulted in a mild correction of the skeletal class II relationship (ANB: - 0.71 ± 0.77°; Wits: - 1.99 ± 1.74 mm) and a protrusion of the lower incisors (2.94 ± 2.52°). Compared to the untreated control group, there was significant distalization of the upper first molars and canines with mesialization and extrusion of the lower first molars.

Conclusion and clinical relevance: CMA is an efficient method for treating class II malocclusions. However, the class II correction is only partially caused by a distalization of the upper molars.