Buccolingual inclination of the mandibular second molars with different anteroposterior skeletal patterns in cone-beam computed tomography

Abstract

PurposeThe purpose of this study was to evaluate the buccolingual inclination of second mandibular molars between groups with varying sagittal skeletal relationship of maxilla and mandible using cone-beam computed tomography (CBCT). Materials and methodsThe sample consisted of 90 adult non-orthodontic treatment patients' CBCT images. They were divided into 3 groups according to sagittal skeletal pattern using Wits appraisal, which were skeletal Class I (13 men and 17 women), skeletal Class II (17 men and 13 women) and skeletal Class III (13 men and 17 women) with an average age of 37.6 years. All subjects had a normal vertical skeletal pattern and had mandibular deviation less than 3mm. Buccolingual inclination was measured in a radiographic software as the angle between the long axis of lower second molars and a reference line tangent to the lower border of the mandibular body. ResultsThere was a statistically significant difference of second mandibular molar buccolingual inclination between the three groups (p=0.000), with a decreasing trend of the inclination angle from skeletal Class II to skeletal Class III. Wits appraisal had a moderate positive correlation with mandibular second molar buccolingual inclination (R=0.648). ConclusionPretreatment patients with different sagittal skeletal patterns have different buccolingual inclination of mandibular molars. These results might affect the preparation of orthodontic appliances or treatment technique.