Nasal septal deviation (NSD) is a common anatomical variation influencing nasal function and maxillary development. This study aims to evaluate the correlation between NSD and maxillary dimensions in a South Indian population using cone-beam computed tomography (CBCT). Additionally, it examines NSD severity and its effect on maxillary dimensions and malocclusion.

The retrospective cross-sectional study analysed CBCT data from patients with NSD aged above 18 years and of South Indian descent, collected between 2022 and 2024, who satisfied the inclusion and exclusion criteria. NSD severity was classified based on the Septal Deviation Angle (SDA) as mild (0–9°), moderate (10–15°), and severe (> 15°). Maxillary parameters such as: palatal width (MPW), length (ML), palatal arch depth (PAD), intermolar width (MIMW), interpremolar width (MPMW) were measured. The association between NSD and maxillary parameters was analysed using the Pearson correlation coefficient. The analysis of variance (ANOVA) was employed to examine the transverse maxillary parameters among three groups with different severity levels.

A total of 140 CBCTs scans were analysed based on the inclusion and exclusion criteria. A weak positive correlation was observed between SDA and PAD (P=0.038), DSW-PAD (P=0.040) and DSW-MPW (P=0.030). MPW was significantly reduced in moderate NSD patients compared to mild NSD (P=0.048). Class II malocclusion was most prevalent across all NSD severities (mild: 20%, moderate: 25%, severe: 15%).

The nasal septal deviation is associated with increased palatal depth and reduced palatal width, particularly in moderate NSD cases.