Evaluation of transverse maxillary growth on cone-beam computed tomography images

This study aimed at quantifying the annual transverse growth of the maxilla using skeletal landmarks in three different regions on cone-beam computed tomography (CBCT) scans. CBCT scans taken before and after orthodontic treatment of 100 child and adolescent patients (50 male, 50 female) without maxillary transverse deficiencies were used to determine the transverse linear distances between the greater palatine foramina (GPFd), the lateral walls of the nasal cavity (NCd), and the infraorbital foramina (IOFd). We found that all distances increased significantly with growth in both genders (p < 0.001). The overall average annual change was 0.5 mm for GPFd, 0.3 mm for NCd, and 0.7 mm for IOFd. Males generally had greater annual changes than females for GPFd and IOFd, but not NCd. There were weak, statistically not significant (p > 0.05) correlations between patient age and the annual changes in GPFd, NCd, and IOFd. These results suggest that the positions of the greater palatine foramina, the lateral walls of the nasal cavity, and the infraorbital foramina change consistently with maxillary transverse growth. Clinicians can use the growth rates as population averages to more confidently estimate the amount of skeletal transverse deficiency or evaluate the long-term effects of maxillary expansion treatment.