Interrelationships between sociodemographic factors, oral health knowledge, behaviours, and caries experience among adults with visual impairment: A cross-sectional study

Background: Adults with visual impairment (AVI) face distinct challenges in maintaining oral health, yet evidence from Malaysia is limited. This study examined the sociodemographic factors associated with oral health knowledge, behaviours, and caries experience, and explored the interrelationships among these outcomes. Methods: A cross-sectional study was conducted at the Malaysian Association for the Blind during two outreach programmes (14 January 2023; 27 January 2024). Oral health knowledge was assessed using the 11-item Malay Health Promotion Questionnaire Index (HPQI). Oral health behaviours and sociodemographic data were self-reported. Caries experience was recorded using the Decayed, Missing, and Filled Teeth (DMFT) index. Descriptive analyses, non-parametric tests, and χ²/Fisher's tests examined associations. Logistic regression was used to model factors associated with oral health knowledge and DMFT. Results: Seventy-five unique participants (mean age 29.6 ± 10.5 years; 64% male) were included. The mean knowledge score was 8.9 ± 2.4, with 74.5% categorised as having good knowledge. Most participants brushed twice or more daily (85.3%) and used toothpaste at least twice daily (86.7%), though one-third reported never flossing. The mean DMFT was 3.48 ± 3.91, driven primarily by missing teeth (40.2%). In bivariate analyses, higher knowledge scores were associated with recent dental attendance, toothpaste use, and flossing frequency (p < 0.05). DMFT correlated strongly with age (p < 0.001). In adjusted models, age (OR = 1.06, p = 0.006), race (OR = 0.14, p < 0.05), and recent dental attendance (OR = 9.64, p = 0.01) were significantly associated with higher knowledge scores. For caries experience, age remained significantly associated with higher DMFT (OR = 1.056, p = 0.001). Conclusion: Despite moderate-to-good oral health knowledge and self-reported behaviours, caries experience remained high among Malaysian AVI. The disconnect between awareness, behaviour, and clinical outcomes underscores that education alone is insufficient. Interventions should integrate accessible, skill-based oral hygiene support and improved preventive and restorative care access.