Traditional methods of assessing orthodontic treatment need using mainly clinical measures are inadequate and would be improved by integrating normative, oral health-related quality of life (OHRQoL), and behavioural propensity measures. This study aimed to develop and test a socio-dental system of orthodontic needs assessment, and to compare normative and socio-dental estimates of orthodontic need. The socio-dental system integrates three types of need: normative need (NN), impact-related need (IRN) and propensity-related need (PRN).
A cross-sectional survey of all 1126 children aged 11–12 years in Suphanburi, Thailand, was carried out to test the new system. The dental health component of the Index of Orthodontic Treatment Need was used to assess NN, and the simplified oral hygiene index for oral hygiene status. Oral impacts were assessed using the child-Oral Impacts on Daily Performances (child-OIDP) index. A self-administered questionnaire recorded information on demographic and oral health-related behaviour. Treatment needs were assessed according to the developed socio-dental system.
The socio-dental approach to assess orthodontic needs was easy to use and readily accepted by the children. The estimates of orthodontic need assessed normatively and socio-dentally differed markedly. The prevalence of NN and IRN was 35.0 and 10.5 per cent, respectively, thus representing a reduction of approximately 70 per cent in the volume of treatment need according to the new method. Children with IRN had different levels of propensity for orthodontic treatment, and therefore required appropriate treatment plans according to their PRN. Of the 10.5 per cent with IRN, 6.9 per cent had high or medium–high PRN, while 3.6 per cent were at medium–low and low levels of propensity.