Changes in the Gingival Thickness and Keratinized Gingival Width of Maxillary and Mandibular Anterior Teeth After Orthodontic Treatment

Abstract

Objectives: To evaluate changes in the gingival thickness (GT) and keratinized gingival width (KGW) of the maxillary and mandibular central and lateral incisors and canines after fixed orthodontic treatment and their association with sagittal tooth movement (STM). Materials and Methods: In this study of both arches, 60 periodontally healthy subjects who had completed fixed orthodontic treatment were included. Using pretreatment and posttreatment lateral cephalograms, STM of the maxillary (1-NA angle and distance, and 1-SN angle) and mandibular (1-NB angle and distance, and IMPA angle) incisors were evaluated to divide the subjects into protrusion and retrusion groups. Pretreatment and posttreatment GT was identified via transgingival probing, and KGW was calculated from the free gingival margin to the mucogingival junction. Results: The intragroup pretreatment and posttreatment comparison results showed a significant decrease in the GT of the maxillary and mandibular anterior teeth in the protrusion and retrusion groups and a decrease in the KGW of the maxillary lateral incisors in the protrusion group. Pearson correlation coefficient analyses for maxillary and mandibular anterior teeth revealed that the GT changes were not significantly associated with STM. However, a positive correlation existed between the KGW of tooth numbers 13 and 41 and STM. Conclusions: STM was not significantly associated with decreased GT of the maxillary and mandibular anterior teeth, but it was positively correlated with the KGW of tooth numbers 13 and 41.