Prevalence of gingival recession after orthodontic tooth movements.

INTRODUCTION: This study was designed to evaluate the long-term prevalence of gingival recession after orthodontic tooth movements, focusing on the effects of mandibular incisor proclination and expansion of maxillary posterior teeth.

METHODS: Records of 205 patients (162 female, 43 male) were obtained from 2 private practice orthodontists. Using pretreatment (age, 14.0 ± 5.9 years) and posttreatment (age, 16.5 ± 6.0 years) lateral cephalograms and dental models, mandibular incisor proclination and maxillary arch widths were measured. Gingival recession was measured based on posttreatment and postretention (age, 32.3 ± 8.5 years) intraoral photographs and models. Associations between tooth movements and gingival recession were evaluated statistically.

RESULTS: Only 5.8% of teeth exhibited recession at the end of orthodontic treatment (only 0.6% had recession >1 mm). After retention, 41.7% of the teeth showed recession, but the severity was limited (only 7.0% >1 mm). There was no relationship between mandibular incisor proclination during treatment and posttreatment gingival recession. Incisors that finished treatment angulated (IMPA) at 95° or greater did not show significantly more recession than did those that finished less than 95°. There were weak positive correlations (r = 0.17-0.41) between maxillary arch width increases during treatment and posttreatment recession.

CONCLUSIONS: Orthodontic treatment is not a major risk factor for the development of gingival recession. Although greater amounts of maxillary expansion during treatment increase the risks of posttreatment recession, the effects are minimal.