title: The Improvement and Completion of Outcome index: A new assessment system for quality of orthodontic treatment.
abstract: OBJECTIVE
  Given the considerable disagreement between the Peer Assessment Rating (PAR) index and the American Board of Orthodontics Cast-Radiograph Evaluation, we aimed to develop a novel assessment system-the Improvement and Completion of Outcome (ICO) index-to evaluate the outcome of orthodontic treatment.
  
  
  METHODS
  Sixteen criteria from 4 major categories were established to represent the pretreatment malocclusion status, as well as the degree of improvement and level of completion of outcome during/after treatment: dental relationship (arch length discrepancy, irregularity, U1-SN, and IMPA); anteroposterior relationship (overjet, right and left molar position, ANB); vertical relationship (anterior overbite, anterior open-bite, lateral open-bite, SN-MP); and transverse relationship (dental midline discrepancy, chin point deviation, posterior cross-bite, occlusal plane cant). The score for each criterion was defined from 0 or -1 (worst) to 5 (ideal value or normal occlusion) in gradations of 1. The sum of the scores in each category indicates the area and extent of the problems. Improvement and completion percentages were estimated based on the pre- and post-treatment total scores and the maximum total score. If the completion percentage exceeded 80%, treatment outcome was considered successful.
  
  
  RESULTS
  Two cases, Class I malocclusion and skeletal Class III malocclusion, are presented to represent the assessment procedure using the ICO index. The difference in the level of improvement and completion of treatment outcome can be clearly explained by using 2 percentage values.
  
  
  CONCLUSIONS
  Thus, the ICO index enables the evaluation of the quality of orthodontic treatment objectively and consecutively throughout the entire treatment process.
authors.affiliation: Department of Orthodontics, Uijeongbu St. Mary's Hospital, the Catholic University of Korea, Uijeongbu, Korea.
authors.forename: Mihee
authors.initials: M
authors.lastname: Hong
authors.affiliation: Department of Orthodontics, Seoul St. Mary's Hospital, the Catholic University of Korea, Seoul, Korea.
authors.forename: Yoon-Ah
authors.initials: YA
authors.lastname: Kook
authors.affiliation: Department of Dental Services Management and Informatics, School of Dentistry, Seoul National University, Seoul, Korea.
authors.forename: Myeng-Ki
authors.initials: MK
authors.lastname: Kim
authors.affiliation: Department of Oral Pathology, School of Dentistry, Seoul National University, Seoul, Korea.
authors.forename: Jae-Il
authors.initials: JI
authors.lastname: Lee
authors.affiliation: Department of Dental Services Management and Informatics, School of Dentistry, Seoul National University, Seoul, Korea.
authors.forename: Hong-Gee
authors.initials: HG
authors.lastname: Kim
authors.affiliation: Department of Orthodontics, School of Dentistry, Seoul National University, Seoul, Korea.; Dental Research Institute, Seoul National University, Seoul, Korea.
authors.forename: Seung-Hak
authors.initials: SH
authors.lastname: Baek
keywords: American Board of Orthodontics Cast-Radiographic Evaluation; Improvement and Completion of Outcome; Orthodontic treatment quality; Peer Assessment Rating Index