Diagnostic value of 3D reconstruction of CBCT and nine zone method of alveolar bone for ambush teeth of anterior maxilla / 中国医学装备

ABSTRACT

Objective:To explore the diagnostic value of three-dimensional(3D)reconstruction of cone beam computed tomography(CBCT)and nine zone method of alveolar bone for ambush teeth of anterior maxilla.Methods:From January 2022 to January 2023,a total of 80 patients with ambush teeth of anterior maxilla were selected from the Stomatology Department of the Third Medical Center of Chinese PLA General Hospital.All patients sought medical attention due to uneven or missing dental alignment.A total of 88 ambush teeth of anterior maxilla were treated.After alveolar bone was conducted by nine zone method,the ambush teeth were found by nine zone method combined with temporomandibular bone CBCT.The number of ambush teeth of anterior maxilla at the outer-upper,outer-middle,outer-lower,middle-upper,middle-middle,middle-lower,inner-upper,inner-middle and inner-lower at the second tooth root of dental crown,as well as the position of the ambush teeth,dental crown positioning and root curvature,were counted by using statistical method.The diagnostic accuracies of two examination methods for the position of ambush teeth,dental crown positioning and root curvature were compared.The comparison of the rates between the nine zone method of alveolar bone and the research results of CBCT was analyzed by using chi square test and other methods.Results:In the 88 ambush teeth,the dental crowns and roots of 50 teeth were at the same side of adjacent teeth,and these of 5 teeth were at between adjacent teeth,and these of 33 teeth were at the different side of adjacent teeth.The most of dental crowns and roots of ambush teeth located in two regions,which were respectively inner-middle and outer-upper regions(23.86%and 19.32%)of maxilla.The diagnostic results of 88 ambush teeth were consistent with the results of intraoperative findings,with a diagnostic accuracy of 100%.The accuracies of the nine zone classification method of alveolar bone in the positions of ambush teeth and dental crown were significantly higher than those of CBCT,and the differences were statistically significant(x2=4.020,1.340,4.460,4.570,0.900,0.930,0.030,0.040,0.200,P<0.05),respectively.Conclusion:CBCT has the advantages of clearness,intuitiveness,accuracy and convenience in the localization of ambush teeth of the anterior maxilla.The nine zone method of alveolar bone has a significance of precise localization for the treatment of complex ambush teeth in the anterior maxilla,and also has a certain guidance value of diagnosis and treatment.