Postretention stability after mandibular incisor extractions assessed by cast and radiograph - The American Board of Orthodontics cast and radiographic evaluation

모형과 방사선 사진을 이용한 하악 전치 발치 치료의 안정성 평가 - 미국교정학회에서 제시한 방법

  • Lee, Jin-Woo (Department of Orthodontics, College of Dentistry, Dankook University)
  • 이진우 (단국대학교 치과대학 치과교정학교실)
  • Received : 2014.06.20
  • Accepted : 2014.08.15
  • Published : 2014.09.30


Purpose: The purpose of this study was to evaluate the improvement and posttreatment stability of patients treated with extraction of lower incisors. Materials and Methods: The total of 20 patients with extracted lower incisors were analyzed by means of diagnostic models and panoramic x-rays at the time of initial, final and after 2 years of retention period of the treatment. Irregularity index, overjet, overbite, tooth size-arch length discrepancy (TSALD), intercanine width, intermolar width and American Board of Orthodontics cast/radiographic evaluation (ABO-CRE) were analyzed. Statistical analysis was performed using Wilcoxon signed-rank test. Results: After treatment, irregularity index showed significant decrease (P = 0.000). TSALD showed significant increase (P = 0.028). During retention period, irregularity index showed significant increase (P = 0.001). For ABO-CRE, total score showed significant decrease after treatment (P = 0.000) and showed average decreased which was not significant result (P = 0.053). Conclusion: Through evaluation of stability of extraction of lower incisors by means of diagnostic models and panoramic x-rays, it can be concluded that lower incisor extraction treatment had been stable for 2 years after treatment.


Supported by : 단국대학교


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