Relationship between alveolar bone thickness, tooth root morphology, and sagittal skeletal pattern : A cone beam computed tomography study.

PURPOSE: The goal of this work was to examine the relationship between sagittal facial pattern and thickness of alveolar bone in conjunction with root morphology of teeth by using cone beam computed tomography (CBCT). METHODS: The study was carried out on the CBCT scans from 3 group of patients (n = 20 in each group). The first group involved skeletal class 1, the second group involved skeletal class 2, and the third group involved skeletal class 3 patients. In all, 14 permanent teeth and interdental regions in the maxilla and mandible were evaluated. Root length and root width were measured on each tooth. Buccal cortical bone thickness, cancellous bone thickness, and lingual cortical bone thicknesses were measured in each interdental region. Analysis of variance, Kruskall-Wallis H and Mann-Whitney U tests were used for statistical comparisons. RESULTS: No significant difference was found between the groups for root length, root width, buccal cortical bone and lingual cortical bone thickness. A significant difference was observed between the groups for cancellous bone thickness as it was thicker in skeletal class 2 group. Cortical bone was thicker in the mandible compared to maxilla on both buccal and lingual sides and it was thicker in the posterior region compared to the anterior region on the buccal side. CONCLUSIONS: Differences in cancellous bone thickness between different sagittal facial patterns and differences in cortical bone thickness between different alveolar regions should be taken into consideration when planning orthodontic tooth movements and anchorage mechanics.

Appraisal of the relationship between tooth inclination, dehiscence, fenestration, and sagittal skeletal pattern with cone beam computed tomography.

OBJECTIVES: To examine the relationship between sagittal facial pattern and dehiscence/fenestration presence in conjunction with buccolingual tooth inclination by using cone beam computed tomography. MATERIALS AND METHODS: The study was carried out on the cone beam computed tomography scans of the following three groups of patients (n = 20 in each group): Class I, Class II, Class III. Buccolingual tooth inclination, buccal dehiscence/fenestration presence, and lingual dehiscence/fenestration presence were evaluated on each tooth. Analysis of variance, Kruskall-Wallis H, Scheffe, and chi-square tests were used for statistical comparisons. RESULTS: Differences (P < .05) were observed between the groups for inclination of upper incisors and all lower teeth except for second molars. Dehiscence prevalence in the upper buccal and posterior buccal regions was higher (P < .05) in the Class I group when compared with the other groups. Lower buccal and anterior buccal regions showed higher (P = .0001) dehiscence prevalence in all groups. No difference was observed in fenestration prevalence between the groups. The upper buccal and anterior buccal regions showed higher (P = .0001) fenestration prevalence in all groups. CONCLUSIONS: Orthodontists must consider concealed alveolar defects in treatment planning to avoid gingival recession or tooth mobility.

Cone Beam Computed Tomography in Orthodontics.

Orthodontists treat malocclusions by applying three-dimensional forces. For years, the diagnosis of this three-dimensional condition and the related treatment plan has been based on two-dimensional imaging. Lateral and anteroposterior cephalometric, panoramic, and periapical radiographs are some of the two-dimensional radiographs routinely used in orthodontics. Despite being highly beneficial in evaluating skeletal and dental relations, these radiographs fail to provide sufficient two-dimensional information in certain cases. The purpose of this compilation is to review the use of cone-beam computed tomography in orthodontics.