Relationship Between Root Angulation and Buccal Bone Wall of the Alveolar Bone in the Maxillary Esthetic Zone Using Cone Beam Computed Tomography (CBCT) in Patients referred to Tabriz Dental School in Years 2020 & 2021

Abstract

Introduction: In implant surgeries, CBCT imaging is usually the most non-invasive method of assessing the morphological features of the alveolar process. Since the presence or absence of thin buccal bone is an aesthetic risk factor, it is crucial for clinicians to have sufficient information about the thickness of the buccal wall before tooth extraction to select the best treatment plan to achieve satisfactory results. The aim of the present study was to measure the angle of the teeth axis in the aesthetic zone and its relationship with the buccal wall thickness in CBCT images. Methods & Materials: 90 CBCT images selected from patients aged 20 to 60 years that were referred to the Oral and Maxillofacial Radiology Department of Tabriz Dental School in 2020 and 2021 Esthetic zone In this study, will be considered as the first right premolars to the first left premolars of the patient's maxilla. The thickness of the buccal bone in sagittal axis measured perpendicular to the longitudinal tooth axis at three different points. With the angle measuring tool, the angle of the longitudinal axis of the tooth and the axis of the basal bone were measured. The images were examined by an observer (maxillofacial radiologist) and the data were recorded in a prepared checklist. To investigate the relationship between wall thickness and root angle, regression models with control of confounding variables (age-gender) were used. Results: The angles of the central teeth were 14.36 + 5.79, lateral 12.02 + 4.54, canine 15.41 + 4.5, and first premolars 15.71 + 4.8. Buccal bone thickness was measured in the area of central tooth 0.38 + 1.05, lateral tooth 0.36 + 1.04, canine tooth 0.31 + 0.91, first premolars 0.31 + 0.83. As the angle of the tooth increases, the thickness of the buccal bone decreases in all areas of the tooth. This relationship is statistically significant in lateral, canine and first premolars regardless of gender and age of patients. (P-value <0.001, p-value <0.001, p-value = 0.003, respectively) but this relationship is not statistically significant in central teeth. (p-value = 0.128) Conclusion: The high incidence of a buccal wall thickness of less than 2 mm in over 80% of the assessed sites indicates the need for additional regeneration procedures, and several locations may also require custom abutments to solve the angulation problems for screw-retained crowns.