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No association between gingival labial recession and facial type.

OBJECTIVE
To evaluate if facial type is a predictor of the development of gingival recession.


METHODS
A cohort of 179 orthodontic patients (76 males, 101 females; age before treatment T S = 12.4 years, SD = 0.8) were followed until 5 years post-treatment (T 5 = 20.7 years, SD = 1.2). The presence of recessions was scored ('Yes' or 'No') by two raters on initial (T S), end of treatment (T 0), and post-treatment (T 5) plaster models. A recession was noted (scored 'Yes') if the labial cemento-enamel junction was exposed. The clinical crown heights were measured at T S, T 0, and T 5 as the distances between the incisal edges and the deepest points of the curvature of the vestibulo-gingival margins. Determination of the facial type was based on the inclination of mandibular plane relative to cranial base (Sella-Nasion/Mandibular Plane) and the proportion of posterior to anterior face heights (PFHs; SGo/NMe × 100 per cent) on pre-treatment cephalograms.


RESULTS
From T 0 to T 5, the number of subjects with recessions increased from 2 (1.1 per cent) to 24 (13.6 per cent), and the number of recession sites increased from 2 to 39. However, most patients had either one or two recession sites. The mean clinical crown height of mandibular incisors increased by 0.86mm (SD = 0.82, P < 0.001). Regression analysis showed that mandibular plane inclination had no effect on the development of gingival recession or on the increase of clinical crown heights of mandibular incisors.


CONCLUSIONS
Facial type is not a predictor of the occurrence of gingival recession.