Emergence Profile Angle as a Determinant of Periodontal Supracrestal Tissue Dimensions in Maxillary Anterior Teeth

This study evaluated the association between the emergence profile angle (EPA) and the phenotypic characteristics of maxillary anterior teeth. Cone-beam computed tomography (CBCT) scans of adult subjects were analyzed to measure EPA, buccal gingival thickness (GT) at different levels, supracrestal tissue height (STH), cementoenamel junction-bone crest distance (CEJ-BC), and bucco-lingual tooth dimensions. Standardized intraoral photographs were used to assess the gingival architecture (GA) and tooth shape. Statistical analyses were performed to explore the correlations between the recorded variables. A total of 100 subjects and 600 maxillary non-molar teeth were included. The overall mean EPA was 14.4° ± 3.06, with significant variation across tooth types (ANOVA, p < 0.001). Sites with a thick gingiva exhibited significantly lower EPA values than those with a thin gingiva. Triangular teeth (15.02°) and teeth with a pronounced scalloped GA (15.9°) had higher EPA than square teeth (13.92°) and those with a flat GA (14.6°) (p < 0.05). EPA revealed a significant negative correlation with GT and STH (Pearson's p < 0.05). Linear regression analysis confirmed that EPA was a predictor of supracrestal soft tissue height (p < 0.001). Therefore, this study concluded that EPA varies according to tooth type, shape, gingival thickness, and architecture, and is inversely correlated with GT and STH.