[Three-dimensional gingival morphology in the aesthetic zone of maxillary anterior teeth: a cone-beam CT analysis].

PURPOSE: To measure and investigate the relationship of three-dimensional gingival morphology on the labial side of the maxillary anterior teeth by using cone-beam CT(CBCT) in conjunction with a novel radiocontrast agent. METHODS: Thirty periodontal healthy subjects were enrolled. The composition of light-cured gingival barrier resin and iohexol injection was applied to the measurement area, then a positioning wire was set up, and CBCT was used to assess supracrestal gingiva tissue (SGT), gingiva thickness (GT) and width of keratinized gingiva (KGW). The differences in each parameter between different gingival biotypes were compared. SPSS 25.0 software package was used for data analysis. RESULTS: The mean distance of SGT was greater for central incisors than canines (P＜0.05). The central incisors had the thickest GT in the maxillary anterior region, while the canines had the thinnest(P＜0.01). The GT of male central and lateral incisors was significantly thicker than that of females(P＜0.05), and the KGW was significantly wider than that of canines (P＜0.05). GT-SGT, KGW-SGT and GT-KGW all had a positive correlation (r=0.315, 0.287,0.406, P＜0.01). The thick gingival type was greater than the thin gingival type in the KGW of lateral incisors and canines and the SGT height of canines (P＜0.05). CONCLUSIONS: There were significant differences in the measuring results of GT, KGW, and SGT in the maxillary anterior region under different gingival biotypes, and individualized treatment strategies can be formulated based on gingival biotypes.