The Alveolar Bone Defect Of Periodontitis Patients With History Of Orthodontic Treatment:A Cone-beam Computed Tomography Evaluation

Objective: This study used CBCT to observe the degree of alveolar bone defects in periodontitis patients with history of orthodontic treatment,and compared with periodontitis patients in non-orthodontic treatment history to find the special teeth types and sites of alveolar bone defects in patients with history of orthodontic treatment,making a preliminary study on the development of alveolar bone defects in periodontitis patients with history of orthodontic treatment,in this way,we can provide guidance for the subsequent periodontal treatment and reference for the fragile site of the alveolar bone during orthodontic treatment.Methods: According to the inclusion and exclusion criteria,the patients were randomly selected from the Department of Periodontology,Affiliated Stomatology Hospital of China Medical University from 2009 to 2019,whose clinical and imaging examinations were consistent with the diagnostic criteria for periodontitis.30 periodontitis patients who had undergone fixed orthodontic treatment and was diagnosed as Angle Ⅱ as orthodontic group.Paired according to age and gender,randomly selected 60 cases of non-orthodontic treatment patients as control group,who have the similar degree of periodontal inflammation with orthodontic group.CBCT was used to measure the degree of alveolar bone defects in the two groups.Statistical analysis the difference of the degree of bone defect,teeth type and sites between the two groups.In orthodontic group,the difference in the degree of alveolar bone defects between the different orthodontic start age was analyzed,both of the orthodontic ending period,and statistical analysis of the distribution of the above indicators.Results: 1.Analysis of the difference of alveolar bone defects in maxillary and mandible position,teeth type,sites,different periodontitis stages in orthodontic group: The degree of alveolar bone defects differed in maxillary and mandible position,teeth type,sites,different periodontitis stages.(1)Difference between maxillary and mandible: In the orthodontic group,the degree of incisor area alveolar bone defect in the mandible was greater than that in the maxillary incisor.The degree of molar area alveolar bone defect in the maxillary was greater than that in the mandible.There was no statistical difference between maxillary and mandible position in the canine and premolar area alveolar bone defect.(2)Differences in the teeth type: In the orthodontic group,the most severe teeth type of the maxillary and mandible alveolar bone was canine area.(3)Differences in the sits: In the orthodontic group,in the incisor side of maxillary,the degree of alveolar bone defect in the mesial and distal side was severer than the buccal and lingual side,in other teeth types,the degree of alveolar bone defect in the buccal and lingual side was severer than the mesial and distal side.Except for the molar area of maxillary and mandible,in the other teeth type,the most serious point of alveolar bone defect in mesial and distal side is buccal measurement point.(4)Difference of periodontitis stages: In orthodontic group,at the stage I periodontitis,the most severe teeth type of the maxillary alveolar bone defect was the molar area,the mandibular heavier teeth type was the incisor area.Along with the periodontal stage became more serious,the most severe part of the maxillary and mandibular alveolar bone defects became the canine area.2.Comparison of the teeth type and sites of the alveolar bone defect degree in the orthodontic group and the non-orthodontic group.(1)Comparison of the teeth type: The contrast between the two groups of patients,in the maxillary canine area and molar area,the mandibular incisor area,canine area and premolar area,the degree of alveolar bone defect in the orthodontic group was severer than that in the non-orthodontic group.There was no statistical difference in the degree of alveolar bone defect between the maxillary incisor area,the premolar area,and the mandibular molar area(P> 0.05).(2)Comparison of the sites: The degree of alveolar bone defect in the buccal side and lingual side of the orthodontic group was greater than that in the non-orthodontic group both in maxillary and mandible.There was no statistical difference between the two groups in the mesial and distal alveolar bone defects.3.Specific analysis of the degree of alveolar bone defect in the first molar in the orthodontic group and the non-orthodontic group: The degree of maxillary and mandible alveolar bone defects in the orthodontic group was greater than that in the non-orthodontic group.The degree of alveolar bone defects in the buccal side,lingual side and distal side of the first molar in the orthodontic group were severer than those in the non-orthodontic group.There was no significant difference in the degree of mesial side alveolar bone defect between the two groups.4.Analysis of the difference of the degree of alveolar bone defects in the orthodontic group with different orthodontic start age and ending period:(1)Within 5 years after the end of orthodontics,patients who started orthodontics before the age of 15 had the most severe alveolar bone defects in all the teeth types compared with those who started orthodontics after the age of 15.(2)For patients with periodontitis within 5 years after the end of orthodontic treatment and 6-10 years after the end of orthodontics,the most severe teeth type of the upper and lower jaw alveolar bone defects area the canine area.In patients with more than 11 years after orthodontic termination,the most severe teeth type of the maxillary alveolar bone defect was the molar area,and there was no significant difference in the degree of alveolar bone defects in the mandible.Conclusions: 1.The most severe teeth in the maxillary alveolar bone defect in periodontitis patients with orthodontic history were the canine area.The degree of incisor area alveolar bone defect in the mandible was greater than that in the maxillary incisor.The degree of molar area alveolar bone defect in the maxillary was greater than that in the mandible.Alveolar bone defects in the buccal and lingual side were mostly larger than the mesial and distal sides both in maxillary and mandible position.2.The degree of alveolar bone defect in patients with periodontitis in orthodontic history was severer than that in patients with non-orthodontic history.The degree of buccal-alveolar alveolar bone defect was significantly different between the two groups.3.Among alveolar bone defects in patients with periodontitis who had different orthodontic termination years,there was differences in the degree of the teeth type,suggesting that there may be alveolar bone remodeling as the number of years of orthodontic termination increases.4.CBCT as a measurement of alveolar bone defects can effectively evaluate the degree and progress of alveolar bone defects in periodontitis patients with orthodontic history,suggesting that the evaluation of the health status of periodontal tissue and the amount of periodontal bone and soft tissue before orthodontics was also very important.Attention should be paid to periodontal maintenance during orthodontic treatment and after the end of orthodontic treatment.