Longitudinal assessment of age-related changes in antegonial notch depth in untreated individuals

The role of the antegonial notch as an indicator of growth remains controversial in the literature. This study examined how antegonial notch depth changes during growth and whether craniofacial morphology is associated with its depth.

A longitudinal sample of 250 untreated healthy individuals (42% female) from the American Association of Orthodontists Foundation Craniofacial Growth Legacy Collection was analysed at three time points: ages 7-8, 13-14, and 17-18 years. Antegonial notch depth was measured from standardized lateral cephalograms. Multilevel general linear regression was applied to evaluate whether skeletal morphology could predict antegonial notch depth.

Antegonial notch depth changed significantly over time (p < 0.001) with a medium effect size. Males consistently had deeper notches than females. Sagittal molar relationships showed no significant influence on notch depth. Multilevel modelling revealed that only the gonial angle was a statistically significant predictor of notch depth (B = - 0.014, p = 0.044), with deeper antegonial notches being measured in individuals with smaller gonial angles, while the intermaxillary angle showed no significant association (p = 0.064). Neither ANB nor the mandibular plane angle had any significant predictive value on antegonial notch depth.

Antegonial notch depth undergoes modest sex-specific changes during adolescence and is minimally associated with craniofacial morphology. Only the gonial angle was a significant predictor (deeper notches in mandibles with smaller gonial angles), suggesting that notch depth primarily reflects localized bone remodelling.