Evaluation of midpalatal suture maturation in young adults using cone-beam computed tomography

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.