Abstract:

Objective To investigate the incidence of dehiscence and fenestration in anterior alveolar bone of 52 adolescent patients with skeletal class Ⅱ and high-angle malocclusion assessed with cone-beam computed tomography, to assist clinical orthodontic treatment. Methods Fifty-two patients aged from 13 to 20 with skeletal class Ⅱ high-angle malocclusion were randomly collected from those who take cone-beam computed tomography（CBCT）examination in Hospital of Stomatology Chengde. Images of all patients were imported to SIDEXIS XG 2.56 software to determine the incidence of the dehiscence and fenestration in anterior alveolar bone. The χ² test analysis was used to evaluate the incidence differences between sex and jaw as well as tooth site respectively. Results The incidence of the alveolar bone defect was 86.53% with the fenestration incidence(65.38%)and the dehiscence incidence(67.30%) respectively.Eighty-two teeth fenestration and 107 teeth dehiscence were detected out of 416 teeth. The incidence of the fenestration in both jaws was similar(P>0.05) whereas the incidence of the dehiscence in maxillary was lower than the mandibular(P<0.05).Difference incidence is positively related with tooth site(P<0.05) but negatively with sex.Conclusion Dehiscence and fenestration of the adolescent patients with skeletal classⅡand high-angle malocclusion are widely existed in anterior alveolar bone area before the orthodontic treatment. The orthodontics should pay close attention to the alveolar morphology before and during the treatment.

Key words: Fenestration, Dehiscence, Skeletal classⅡand high-angle malocclusion, SIDEXIS XG 2.56 software measurement, Cone-beam computed tomography, Adolescent 