title: Orthodontic treatment complexity and need in a group of Nigerian patients: the relationship between the Dental Aesthetic Index (DAI) and the Index of Complexity, Outcome, and Need (ICON).
abstract: OBJECTIVE
  The aim of this retrospective analytical study was to assess the relationship between the Dental Aesthetic Index (DAI) and the Index of Complexity, Outcome, and Need (ICON) on the orthodontic treatment need and complexity in a group of Nigerian patients.
  
  
  METHODS
  Fifty-six cases were randomly selected from the model storage of the orthodontic unit of the University College Hospital in Ibadan, Nigeria. The ICON was used to assess the pre-treatment study models for orthodontic treatment need and complexity of the cases while the DAI was also used to assess the same cases for treatment need. Descriptive statistics as well as the non-parametric (Spearman Rank-Order and Pearson's Product Moment) correlations were used to analyze the data.
  
  
  RESULTS
  The mean ICON and DAI scores were 67.38+/-19.63 (SD) and 42.27+/-12 .66 (SD), respectively. Both the ICON and DAI agreed that one (1.8%) case did not need treatment while 46 (82.1%) needed treatment. All the difficult and very difficult cases according to the ICON were assessed as needing treatment by the DAI with 18 (13.1%) out of 22 (39.3%) in the very difficult category belonging to the handicapping group where treatment was mandatory. In all positive significant correlations were recorded for the ICON and DAI scores.
  
  
  CONCLUSIONS
  The ICON and DAI showed favorable agreement when used to assess treatment needs through the use of study casts. The ICON could be a good substitute for the DAI in assessing pre-treatment needs of Nigerian patients.
authors.affiliation: Department of Child Oral Health, Faculty of Dentistry, College of Medicine/University College Hospital, University of Ibadan, Ibadan, Nigeria. coonyeaso@yahoo.com
authors.forename: Chukwudi Ochi
authors.initials: CO
authors.lastname: Onyeaso
mesh_terms: D003753:Dental Health Surveys; D004955:Esthetics, Dental; D005260:Female; D006301:Health Services Needs and Demand / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000175:diagnosis / Q000453:epidemiology*; D009549:Nigeria; D009971:Orthodontics, Corrective / Q000706:statistics & numerical data*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018709:Statistics, Nonparametric