ĐỘ DÀY XƯƠNG Ổ RĂNG HÀM DƯỚI Ở VÙNG RĂNG NANH VÀ RĂNG HÀM NHỎ CỦA NGƯỜI BỆNH CÓ TƯƠNG QUAN XƯƠNG LOẠI I TRÊN PHIM CT CONEBEAM

Abstract

Objectives: To describe craniofacial indices in patients with skeletal Class I and varying facial types based on standard lateral cephalometric radiographs, and to assess the thickness of the mandibular alveolar bone in the canine and premolar regions using cone-beam computed tomography (CBCT), as well as its correlation with facial types. Subjects and methods: This case series study was conducted on patients aged 18-47 years who underwent both lateral cephalometric radiography and CBCT at the Center for Advanced Dentistry, Hanoi Medical University, from July 2024 to June 2025. Results: On lateral cephalometric radiographs, the SNA and SNB angles increased progressively across high–average–low facial types (81.1°–83.2°–84.8° and 77.8°–80.6°–82.6°, respectively). In CBCT analysis, the greatest buccal bone thickness was found at the second premolar region, 6 mm apical to the cementoenamel junction (CEJ) (1.58–1.74–1.98 mm for high–average–low facial types, respectively), while the smallest was observed at the canine region, 2 mm apical to the CEJ (0.59–0.58–0.70 mm for high–average–low facial types, respectively). The greatest lingual bone thickness was also at the second premolar region, 6 mm from the CEJ (3.98–4.00–4.58 mm for high–average–low facial types, respectively), whereas the smallest was recorded at the first premolar region, 2 mm from the CEJ (0.59–0.52–0.92 mm for high–average–low facial types, respectively). The variation pattern of bone thickness was consistent across different facial types. Conclusion: Alveolar bone width increased in the apical direction across all three studied teeth and among all three facial types. Facial morphology had a significant influence on alveolar bone thickness: buccal bone thickness was inversely related to facial angle, while lingual bone thickness showed a direct correlation.