Antegonial Notch Depth and Mandibular Growth: A Longitudinal Multilevel Modelling Approach

Introduction: The antegonial notch has been proposed as a morphological indicator of mandibular growth, yet its developmental trajectory and predictive value remain insufficiently explored. This study examined how the antegonial notch changes across growth and whether craniofacial morphology can predict its depth. Methods A longitudinal sample of 250 untreated individuals (42% female) was analysed at three ages: 7/8, 13/14, and 17/18. Antegonial notch depth was measured from lateral cephalograms. A mixed repeated-measures ANOVA tested the effects of age, sex, and Angle molar classification, while multilevel general linear regression evaluated whether skeletal morphology predicted antegonial notch depth. Results Antegonial notch depth changed significantly over time ( P  < 0.001). Males consistently had deeper notches than females. Shallowing of the antegonial notch was generally seen in both sexes between ages 7 and 14 but deepened thereafter in males. Angle molar classification showed no significant influence on notch depth. Multilevel modelling revealed only the gonial angle as a significant predictor (B=–0.014, P  = 0.044) to notch depth. Conclusion Antegonial notch depth undergoes modest sex-specific changes during adolescence and is minimally associated with craniofacial morphology, with only the neighbouring gonial process being a significant predictor possibly reflecting the view that antegonial notch depth primarily reflects localized bone remodelling.