The Application Of Cone Bean CT In The Evaluation Of Alveolar Bone Morphology In The Anterior Teeth Of Patients With Skeletal Class Ⅱ Malocclusion

Objectives:The thickness of labial alveolar bone in different positions of anterior teeth of skeletal Class Ⅱ malocclusion patients was studied by Cone beam CT(CBCT),to understand the characteristics of labial alveolar bone in anterior region of skeletal Class II malocclusion patients,to provide accurate and reliable reference for the treatment plan design of this kind of patients,to prevent the occurrence of bone initiation and fracture.Methods:CBCT images of 59 cases were collected,including 20 cases in Class Ⅱ i division group,20 cases in Class II ii division group and 19 cases in individual normal occlusion group,the thickness of labial Alveolar bone was measured at the apex,the Middle 1/3 segment and the neck 1/3 segment of the anterior teeth in the case group and the Control Group.Results:1)the thickness of labial alveolar bone in different positions of maxillary and mandibular anterior teeth was the largest in individual normal tooth group,the second in Class Ⅱ and the smallest in Class Ⅱ and Class Ⅱ.The thickness of labial alveolar bone in apical part was the largest,and the thickness of 1/3 segment of cervical part was the smallest.2)the Alveolar bone on the labial side of the left upper cuspid is the thinnest among the different tooth positions,the alveolar bone on the labial side of the right lower cuspid is the thinnest among the right lower cuspid and the alveolar bone on the labial side of the left lower cuspid is the thinnest among the different tooth positions.Conclusion:The labial Alveolar bone is the thinnest in Class Ⅱ bispecific bone,especially in canine labial bone,which should be treated with light force in order to avoid bone fenestration and bone dehiscence.