Adjustable selective maxillary expansion combined with one-stage maxillomandibular surgery: A prospective study of osseous widening in fifty-five consecutive patients

Objective

SARME is often considered to be the only available treatment for significant or severe maxillary transverse palatal deficiencies (MTD) in skeletally-mature patients. Despite this observation, the aim of our study was to assess a new type of maxilla distraction osteogenesis. Using two innovative tools, we performed selective expansion: the site to be widened and the amount of increase were both pre-selected. Patients were treated in a single maxillomandibular procedure. Our study focuses primarily on the extent of osseous widening.

Study design

Post-expansion computed tomography data from 55 non-syndromic patients were included in a prospective study and analyzed in two planes for transverse skeletal widening. Of the 55 patients, 16 underwent isolated posterior distraction for severe posterior endognathia (group I), and 39 were treated in both segments (group II). Diastemas and anterior spaces permitted resolution of crowding and patients with a small, narrow, tapering arch were given a more rounded form. All patients underwent a complete Le Fort I with down fracture. Two novel devices were used: first, an adjustable distractor to achieve an angular opening; and secondly, in group II, new modular plates interlocked for osteosynthesis to provide stability and anterior expansion.

Results

In group I, analysis of the width of the gain showed significant posterior values decreasing from back to front, a result never achieved with the SARME procedure. The mean osseous gain at first molars was 7.1 mm. When anterior space was required in group II, it was created as wide as needed (mean 4.2 mm, at canine level) with good preservation of the 1st molar space gain (mean 6.8 mm).

Conclusion

Total Le Fort I osteotomy associated with two innovative devices provides a new, segmental and adaptable approach for transverse distraction osteogenesis. We demonstrate a good match with the dental enlargement required. All patients were managed in a single orthognathic procedure for all the anomalies to be treated. Long-term results show good stability.