Development of a conceptual model of oral health for malocclusion patients

OBJECTIVES: To provide an empirical test of the applicability of Locker's conceptual model of oral health for malocclusion patients, and to suggest alternative models of the effect of malocclusion on well-being.
MATERIALS AND METHODS: Data from a survey of 323 adolescents attending for orthodontic treatment were analyzed to develop a new oral health model for malocclusion patients. Oral health-related quality of life (OHRQoL) was measured using the 14-item Oral Health Impact Profile; malocclusion was measured using the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN). Using structural equation modeling, the relationship between conceptual domains in Locker's model was explored and three models of their interrelationship tested for goodness of fit.
RESULTS: Fit indexes for Locker's model indicated that it did not fit the data well. Therefore, a modified model was developed to incorporate additional paths between other levels to better fit the data. The best fit was provided by a model in which the direct effects of malocclusion on pain, discomfort, and handicapping-and the direct effect of pain on disability-were removed. A direct effect of functional limitation on disability was allowed. The modified Oral Health Impact Profile model proved to be a good fit to the data (root mean square error of approximation  =  0.069).
CONCLUSION: The pathways identified in Locker's (1988) conceptual model of oral health may not be appropriate for describing the relationships between OHRQoL constructs in individuals with malocclusion. An alternative model is proposed.
KEYWORDS: Malocclusion; Oral Health Impact Profile; Oral health–related quality of life