Evulation Of Bone Morphology And Three Dimensional Position Of Teeth In Lower Incisor's Region In Adult With Skeletal Class ? Malocclusion

ObjectiveTo evaluate the relationship between lower incisor position and lower alveolar bone morphology of adult skeletal class ? malocclusion subjects with different vertical skeletal types by using Cone Beam Computed Tomography(CBCT).Materials and MethodsCBCT records of 60 adult class ? skeletal patients(18-36 years old)who were taken treatment in Affiliated Stomatology Hospital of Guangxi Medical University,Department of Orthodontics from May 2015 to February 2018 were divided according to facial types,hyperdivergent,normodivergent and hypo divergent subgroups.Each group 20 people(10 male and 10 female).The DICOM data was imported into the Mimics software for secondary reconstruction that generates three-dimensional(3D)projections of images withmaximum intensity to obtain the sagittal cross section.Lower right central incisor was selected for measurement.The measurement of the labial and lingual alveolar bone thickness,lower incisor inclination,labial and lingual alveolar bone angle of lower incisor was done.By using SPSS 18.0 software,Univariate general linear model analysis,One way ANOVA test and Pearson correlation analysis were performed for statistical analysis to investigate the relationship between gender,incisal inclination,vertical skeletal pattern,alveolar bone angle and bone morphology of the lower incisors.Results1.The labial and lingual alveolar bone thickness of hyperdivergent groups was lesser than the normodivergent and hypodivergent groups.No statistically significant difference was detected between normodivergent and hypodivergent groups.The labial and lingual alveolar bone thickness was lesser in female than male.2.There was a statistically significant difference between the lower incisor inclination in different vertical facial patterns.Hypodivergent groups>normodivergent group >hyperdivergent group.3.There was a positive correlation between lower incisor inclination and labio-lingual alveolar bone angle.4.The labial and lingual alveolar angle of hyperdivergent groups was smaller than normodivergent and hypodivergent groups.ConclusionThe lower incisor alveolar bone morphology of adult skeletal class ? malocclusion was significantly correlated with the gender and vertical facial pattern.The movement of the tooth is limited by the morphology of the alveolar bone.The alveolar bone thickness of high angle patient is thinner than the others so it can be at increased risk of resorption of alveolar bone and bone dehiscence can occur.In clinical practice,it is necessary to consider the alveolar bone morphology and the lower incisor position when determining the treatment plan in order to avoid the iatrogenic sequelae.