Correlation between the Sagittal Skeletal Nasal Profile Morphology and Skeletal Class III Malocclusion in a Group of Yemeni Adults

Abstract

This cross-sectional descriptive analytical study aimed to assess the correlation between sagittal skeletal nasal-profile morphology and skeletal Class III malocclusion in a group of Yemeni adults, and to evaluate the influence of cranial base, maxillary and mandibular dimensions, vertical growth pattern, and sex. The study was performed at orthodontic centers in Sana’a, Yemen. The sample comprised 100 Yemeni adults with diagnosed skeletal Class III malocclusion (50 males, 50 females; mean age 20.9 ± 2.98 years). Standardized lateral cephalograms were acquired and landmarked to measure sagittal nasal parameters, cranial base lengths/angle, maxillary dimensions and mandibular metrics, in addition to vertical and angular indices. Statistical analyses included descriptive statistics, Pearson/Spearman correlations, t-tests/Mann–Whitney comparisons, one-way ANOVA/Kruskal–Wallis and Scheffé post-hoc testing; significance was set at p ≤ 0.05. The study results showed that the mean nasal bone length and nasal bone distance were 23.41 ± 3.78 mm and 38.84 ± 5.21 mm, respectively. nasal bone length correlated negatively with Sella Nasion to Point A Angle (SNA) (r = −0.201, p = 0.045), while both nasal bone length and nasal bone distance correlated positively with the W angle. nasal bone distance demonstrated strong positive correlations with anterior cranial base (N–S; r = 0.649, p < 0.01) and with mandibular projection (N–Pog; r = 0.825, p < 0.01). Maxillary measures (Co–A, ANS–PNS) were significantly associated with sagittal nasal metrics (p < 0.01). Hyperdivergent subjects showed greater R–A, N–A and N–ANS than hypodivergent subjects (p < 0.05). Males exhibited larger linear cranial-facial measures and R –A than females, whereas nasal curvature (NIN2R) did not differ by sex. The study concludes that nasal morphology in Yemeni adults with skeletal Class III malocclusion is heterogeneous and significantly influenced by maxillomandibular relationships, cranial base structure, vertical growth pattern, and sex, underscoring the multifactorial nature of nasal and midfacial morphology and the need for individualized assessment.