Surgically assisted, rapid maxillary expansion in adults. A retrospective long-term follow-up study.

This study presents a technique for surgically assisted, rapid maxillary expansion performed on 20 patients and the results after orthodontic treatment. The mean age of the patients was 36.3 years and on average they had been followed-up for 3 years and 6 months. The results seemed to be reliable long-term. The definitive expansion in the first molar region was 7.1 mm +/- 2.4 and in the canine region 4.8 mm +/- 2.7. The relapse measured after the observation period, was in the corresponding regions 1.2 mm +/- 1.3 and 0.2 mm +/- 2.1. The study also seemed to support the theory that the suture, anterior to the incisive canal, never ossifies until very late in life.