Malocclusion traits and oral health-related quality of life in Finnish adults.

AIM: The aim of this study was to examine the association of increased overjet, cross-bite/scissor-bite and increased overbite/open bite with oral health-related quality of life (OHRQoL) among Finnish adults using nationally representative data.

METHODS

Part of the data from the Health 2000 Survey, Finland, was used in this study. A total of 4711 people were included, representing adults aged ≥30 years. The outcome variable was OHRQoL severity which was measured using the 14-item Oral Health Impact Profile (OHIP-14). Three malocclusion traits (increased overjet, cross-bite/scissor-bite and increased overbite/open bite) were used as explanatory variables. Age group, marital status, education level, income, employment status, having at least one decayed tooth or periodontal pocket ≥6 mm, the number of contacting pairs of teeth, denture status and self-reported general health status were controlled for. A series of multivariable zero-Inflated Poisson (ZIP) models were used to calculate incidence rate ratios (IRR) for the nonzero scores and odds ratios (OR) of having no event.

RESULTS

The weighted prevalence of increased overjet was 8.4%, while it was 23.6% for cross-bite/scissor-bite and 6.7% for increased overbite/open bite. The mean (SE) OHIP-14 (OHRQoL severity) was 2.8 (0.92); the mean score was highest in the pain domain and lowest in the physical and social disability domains. The mean OHIP-14 score was higher in people with increased overjet but not significantly different in people with cross-bite/scissor-bite or with increased overbite/open bite. In multivariate ZIP models, people with increased overjet had a 10% higher OHIP-14 score than people with normal overjet. Increased overjet was associated only with the physical disability domain. Cross-bite/scissor-bite was associated only with the social disability domain, and psychological disability was associated with increased overbite/open bite.

CONCLUSION

People with increased overjet had significantly poorer OHRQoL than people with normal overjet in a nationally representative population of Finnish adults ≥30 years. Other malocclusion traits were not associated with OHRQoL. However, all three malocclusion traits were associated with either physical or psychological or social disability domains of the OHRQoL.