Dental self-care and visiting behaviour in relation to social inequality in caries experience.

OBJECTIVES: To investigate associations of dental behaviour with social inequality in oral health.
METHODS: A random sample of 45-54 year-olds from Adelaide, South Australia was surveyed by self-complete questionnaire in 2004-05 (n = 879, response rate 43.8%). Oral examinations were performed by calibrated dentists on 709 persons (80.7% of participants).
RESULTS: The mean (SE) number of decayed teeth (D) was 0.4 (0.04), with 5.3 (0.2) missing teeth (M), 11.0 (0.2) filled teeth (F) and 16.6 (0.2) DMFT. The majority brushed their teeth 8 or more times per week (78.8%) and had made a dental visit within the last 12 months (63.7%). Nearly a quarter had a household income of under $30,000 (24.0%). Multivariate analysis showed a three-way interaction (p < 0.05, GLM) between income and brushing and visiting for decayed teeth, showing that the relationship between decayed teeth and dental behaviour varied across levels of income. Among those who had not made a dental visit in the last 12 months, those who brushed their teeth 8 or more times per week in the low income group had D = 0.7 (0.2) while those who brushed less often had D = 2.2 (0.5) compared to D = 0.3 (0.08) and D = 0.3 (0.2) respectively in the high income group.
CONCLUSION: Dental behaviour in terms of brushing and visiting was associated with social gradients in oral health for decayed teeth across income groups, with less favourable dental behaviour having a stronger negative association with oral health among lower income groups.