Abstract
BACKGROUND: The clinical success of maxillary expansion depends largely on the degree of maturation of the midpalatal suture (MPS). Although cone-beam computed tomography (CBCT) allows direct visualisation of the MPS, most previous studies have relied on conventional orthogonal image planes, which may not fully reflect the complex three-dimensional course of the suture. This study introduces a novel oblique-slice CBCT evaluation protocol and investigates the relationship between MPS maturation, cervical vertebral maturation (CVM), and chronological age. METHODS: This retrospective study evaluated MPS maturation in 100 young adults (53 females, 47 males; median age: 24 years; range: 17–32 years) using full-field-of-view CBCT. MPS maturation was classified into five stages (A–E) using the proposed oblique-slice reconstruction protocol, implemented with Horos software. CVM stages were determined from CBCT-derived cephalometric images using a widely accepted method. The relationships between MPS maturation stage, CVM stage, and chronological age were analysed. RESULTS: MPS fusion (stages D + E) was observed in 74% of participants, with a prevalence of 79.2% in female and 68.1% in male patients. Chronological age showed a weak positive correlation with MPS maturation (r = 0.205, p = 0.040), but no significant correlation was found between CVM stage and MPS maturation (p > 0.05) in the overall sample. Among male patients, advanced MPS stages were associated with older age (p = 0.044) and a greater distribution of CVM stages (p = 0.023). No significant associations were observed in female patients. CONCLUSION: In young adults, chronological age and CVM stage alone are unreliable indicators of MPS maturation. The proposed oblique-slice CBCT evaluation protocol may provide a more anatomically accurate assessment of the MPS. This may support more reliable clinical decision-making, particularly in borderline cases where nonsurgical maxillary expansion is being considered.