Analysis Of Cone Beam CT In Maxillary And Mandibular Anterior Alveolar Bone Defect Before Orthodontic Treatment

Abjective: Cone Beam computed tomography(CBCT)was used to measure the occurrence of fenestration and dehiscence in the maxillary and mandibular anterior and the relationship between gender,age,different sagittal facial type,different vertical plane shape,alveolar bone thickness of 3,6,and 9mm below the enamel-dentinal junction and the occurrence of fenestration and dehiscence.Methods and Materials: 161 cases of pre-treatment CBCT were randomly selected from patients who were treated at the First Orthodontics Department of the Affiliated Stomatological Hospital of China Medical University from 2014 to 2018,and the data were imported into Proplan 1.5 software for measurement,and the Generalized Estimation Equation(GEE)was applied to make a statistical analysis of the relationship between the incidence of fenestration and dehiscence of the 1932 teeth in the maxillary and mandibular anterior and the gender,age,sagittal facial type,vertical facial type,and the thickness of the alveolar bone at 3、6、9mm below the enamel-dentinal junction.Results: In the maxillary and mandibular anterior,the total incidence of fenestration was 18.47%,and the total incidence of dehiscence was 13.30%;wherein,the incidence of maxillary fenestration was 21.22%,and the incidence of maxillary dehiscence was 7.76%,while the incidence of mandibular fenestration was 15.73%,and the incidence of mandibular dehiscence was 18.85%.Fenestration tends to occur in the maxilla,and dehiscence tends to occur in the mandible.Age has significant statistical significance on the occurrence of fenestration and dehiscence in the maxillary anterior(P<0.01);the thickness of the alveolar bone at 3mm and 6mm below the enamel-dentinal junction is statistically significant for the occurrence of mandibular fenestration(P<0.05);the vertical facial type is statistically significant for the occurrence of dehiscence in the mandibular anterior(P<0.05).Conclusions: The alveolar bone in the maxillary and mandibular anterior of patients before orthodontic treatment has a high degree of fenestration and dehiscence,with fenestration more likely to occur in the maxilla,and dehiscence more likely to occur in the mandible.The greater the alveolar bone thickness at 3mm below the enamel-dentinal junction is,the higher the incidence of fenestration.The greater the alveolar bone thickness at 9mm below enamel-dentinal junction is,the smaller the incidence of fenestration.With the increase of age,the risk of maxillary fenestration and dehiscence is on the rise.