Quantitative Evaluation of Buccal Cortical Bone in Maxillary Posterior Region on Cleft and Non-cleft Side in Cleft Lip and Palate Patients; A Three-Dimensional Cone Beam Computed Tomography Study

Objective: The study aimed to evaluate the buccal cortical bone thickness in the maxillary posterior region on both cleft and non-cleft sides of patients with unilateral cleft lip and palate (CLP) and to identify the optimal site for mini-implant placement, which is critical for the success of orthodontic treatments in these patients. Methods: This cross-sectional study was conducted on 30 CLP patients (aged 8–25 years) using Cone Beam Computed Tomography (CBCT) scans to measure cortical bone thickness at four vertical levels (2mm, 4mm, 6mm, and 8mm) in three interradicular regions: between the first and second premolar (P-P), second premolar and first molar (P-M), and first and second molar (M-M). Data were analyzed using descriptive statistics, One-Way ANOVA, and independent t-tests, and intraobserver reliability was assessed. Results: The study found that the P-M region had the highest mean cortical bone thickness, followed by P-P and M-M. Bone thickness increased with vertical height from the cementoenamel junction (CEJ), with the thickest bone observed at 8mm. The non-cleft side exhibited a slightly higher mean cortical bone thickness than the cleft side, though this difference was not statistically significant overall. However, significant differences were observed at specific heights (2mm, 4mm, and 6mm), with the non-cleft side showing thicker cortical bone. Conclusion: The study suggests that mini-implant placement at greater vertical heights (6mm or 8mm) in the maxillary posterior region is recommended due to increased cortical bone thickness. Although the non-cleft side generally showed thicker cortical bone at lower heights, the cleft side may still be viable for mini-implant placement at more apical regions. These findings provide valuable guidance for clinicians in selecting optimal mini-implant sites in CLP patients, which can enhance the success of orthodontic treatment and anchorage stability.