12 August 2022

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The combined use of computer-guided piezocision and clear aligners: a prospective clinical study

Authors: M. Cassetta, F. Altieri

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The use of piezoelectric bone surgery has led to the development of minimally invasive corticotomy protocols. The peculiar characteristics of piezoelectric surgery is represented by an extremely precise and selective micrometric cutting on hard tissues that has simplified and made corticotomic procedures more safety.

The aim of this prospective study was to evaluate the efficacy in the daily clinical practice of minimally invasive computer-guided piezo surgery associated with orthodontic treatment with transparent aligners. It has been hypothesized that this method reduces the duration of orthodontic treatment time (primary outcome), does not cause periodontal damage and does not adversely affect the quality of li- fe of the patient (secondary outcome).

MATERIALS AND METHODS
10 patients were selected for the study. The surgery was performed with piezoelectric handpiece and guided by a CAD/ CAM surgical template with 3D control of the piezoelectric surgery micro-saw. Corticotomic engravings were designed and performed for all patients in correspondence of the interdental spaces where it was possible to engrave without risk of damage to the limiting anatomical structures. The orthodontic treatment started immediately after the surgery with the insertion of thermoplastic aligners. Evaluation of primary and secondary outcomes were performed and statistically analyzed.

RESULTS
The orthodontic treatment was completed in a third of the scheduled time. There was not a statistically significant difference between the pre- and post-operative periodontal indexes, or deterioration in oral health-related quality of life (OHRQoL).

DISCUSSION
The hypotheses of the study were confirmed. Minimally invasive corticotomy (computer-guided piezocision), performed with a piezoelectric handpiece and guided by a CAD/CAM surgical design using the 3D printing process, allowed the correction in one third of the therapeutic time, without damaging the periodontal tissues or by adversely affecting the quality of life of the patient. The described technique is safe, effective and predictable with low impact on OHRQoL.

CLINICAL SIGNIFICANCE
The combined treatment of corticotomy and transparent aligners has been shown to be applicable in different clinical condi- tions. The underlying mechanism of dental-alveolar corticotomy is to induce, through a bone incision, a state of transitory focal osteopenia, capable of accelerating dental displacement through the application of orthodontic mechanics.