The relationship of 2 professional occlusal indexes with patients' perceptions of aesthetics, function, speech, and orthodontic treatment need.

The aim of this study was to determine the relationship between patients' perceptions of orthodontic treatment need and need as determined with professionally derived indexes, namely the dental aesthetic index and the index of orthodontic treatment need. This study was undertaken at orthodontic offices in San Francisco, Calif. The pretreatment study casts of 50 consecutive patients, presenting for orthodontic treatment, were objectively assessed with these indexes by 2 examiners trained and calibrated in their use. Patients were asked to complete a questionnaire consisting of 4 questions addressing appearance, function, speech, and treatment need, using either a 5-point Likert scale or a yes/no response. The professionally derived indexes showed that statistically significant correlations existed between the aesthetic component and dental health component (r = 0.46; P <.01), the aesthetic component and dental aesthetic index (r = 0.54; P <.01), and the dental health component and dental aesthetic index (r = 0.46; P <.01). Statistically significant correlations were also found for subjective assessments between biting/chewing and speech (r = 0.31; P <.05), between speech and the aesthetic component (r = -0.39; P <. 01) and the dental aesthetic index (r = 0.34; P <.05), and between the aesthetic component and appearance (r = -0.28; P <.05). Logistic regression analysis after dichotomization (treatment/no treatment need) confirmed that the aesthetic component was the only statistically significant factor (odds ratio, 0.57; 95% confidence limits 0.34 to 0.97).