Three-dimensional digital planning of class III decompensation with clear aligners: Hard and soft tissue augmentation with concomitant corticotomy to stretch the limits of safe orthodontic treatment.

Purpose: Three-dimensional diagnosis has shown that orthodontic therapy could potentially move the roots of the teeth outside the original bone structure. The purpose of these case studies was to test the possibility of obtaining correct three-dimensional tooth positioning with clear aligners, thereby modifying the periodontal structure accordingly, at the same time.

Methods: Regenerative Corticotomy (RC) was performed with clear aligners on ten adult patients (40 anterior teeth) with skeletal Class III malocclusion, for dental decompensation, prior to the orthognathic surgery. The CBCT examinations were performed before treatment (T0) and 1 year after orthognathic surgery (T1). The vertical and the horizontal hard tissue changes, the width of keratinized gingiva, the incisors proclination (IMPA) and the percentage of inclination compared to the planning were analyzed.

Results: The distance between the Cemento-Enamel Junction (CEJ) and the Bone Marginal Level (BML) decreased in average from 5.5 ​± ​3.2 ​mm to 1.39 ​± ​0.53 ​mm. The horizontal changes were at the 3 ​mm level 1.42 ​± ​0.5 ​mm, at the 5 ​mm level 1.98 ​± ​0.66 ​mm and at the 7 ​mm level 2.70 ​± ​0.87 ​mm. The width of Keratinized gingiva changes were on average 1.42 ​± ​0.36 ​at T0 and 4.16 ​± ​2.25 ​at T1. All the changes were statistically significant with p ​< ​0,05. The mean proclination based on IMPA values was +9.16 +-1.19°. The mean difference of the incisor's proclination compared to the digitally planned was -1 +-0.6° (89.87 +- 6.46%).

Conclusion: Clear Aligners with three-dimensional digital planning seems to be reliable in controlling teeth movements in the pre-orthognathic decompensation phase. Regenerative Corticotomy seems to have the ability to improve the periodontal tissues despite proclination.