Objectives: To assess the treatment outcome of patients who completed their orthodontic treatment by using Andrews' six elements and the American Board of Orthodontic (ABO) objective grading system (OGS); to determine whether Andrews' six elements can be used as a new assessment system for patients who completed their orthodontic treatment.
Methods: A total of 160 patients who completed their orthodontic treatment were included in the study. The participants were randomly selected from patients who completed their orthodontic procedures in Kunming Medical University Affiliated Stomatological Hospital during the period of 2015 to 2019. The retrospective completed cases were examined in accordance with the Andrews' six elements and ABO measuring scales. Scores were assigned to each tooth in each category. All the measurement items in both evaluation criteria, the composite category score, and the total score were calculated. The passing and potential passing rates of the completed cases were compared with two measuring scales via the Chi-square test.
Results: The passing rate for the evaluation of cases by using the Andrews' six elements measuring scale was 83.8%, and that for the evaluation of cases by using the ABO measuring scale was 86.3%. The differences in achieving the standard between the cases of Andrews' six elements and ABO-OGS via the Chi-square test were statistically insignificant (P>0.05). The mean Andrews' six elements score for the completed cases: the category of the anteroposterior change in position of the incisors contributed the most, whereas the core discrepancy presented the least percentage in total scores. In ABO-OGS, alignment and marginal ridges contributed the most, whereas interproximal contacts exhibited the least percentage in total scores.
Conclusions: The performance of Andrews' six elements was comparable with that of ABO-OGS in assessing the treatment outcome of patients who completed their orthodontic treatment. Andrews' six elements can be used as a new system for assessing the treatment outcome of patients who completed their orthodontic treatment. It demonstrated particular advantage in controlling facial profile, and had just completed material of patients who completed their orthodontic treatment it can measure. The Andrews' six elements measuring scale is convenient to disseminate and use.
目的: 使用Andrews六要素与美国正畸学会客观评分系统（ABO-OGS）对正畸结束病例进行评价，探讨Andrews六要素能否作为矫治结束病例新的评价体系。方法: 在2015—2019年经昆明医科大学附属口腔医院正畸科医生采用直丝弓矫治技术治疗完成的错畸形病例中，随机选择完成错治疗的160例患者作为研究对象，参考Andrews六要素与ABO-OGS测量标准，使用Andrews 六要素测量尺及美国正畸学会（ABO）测量尺对研究对象的模型和X线片进行测量与计分，测量这2种评价标准中的所有测量项目，记录每个病例的各单项计分及总计分，分析比较经2种测量尺测量后病例测量计分情况，并进行统计学检验。结果: 经Andrews六要素测量尺测量后病例通过率为83.8%，ABO测量尺测量后病例通过率为86.3%，2种测量尺测量后病例通过情况的差异无统计学意义。在Andrews六要素的各单项评价标准中：切牙前后位差异的计分均值占总计分的比例最高，而牙弓核心线计分在所有单项中最低。在ABO-OGS的各单项评价标准中：牙齿排列与边缘嵴高度占总计分的比例最高，邻接关系计分在所有单项中最低。结论: Andrews六要素与ABO-OGS对正畸结束病例的评价具有较好的一致性，Andrews六要素可以作为一种新的评价体系进行矫治结束病例的评价，而且其对矫治病例的面部软组织侧貌的把控存在一定的优势，在进行结束病例的评价时只需要病例资料完整，可进行临床推广应用。.
Keywords: American Board Orthodontic Objective Grading System; Andrews six elements; finished orthodontic treatment; treatment efficiency.