Social Inequities in Access to Dental Care in Australian Adults over Time.

Introduction: Social inequities in dental caries are reflected by both inequities in the social structures that contribute to disease severity and inequities in the provision of dental care. This study aimed to describe social differentials in the dental caries experience among Australian adults across a 13-y period and to examine if the highest magnitude of oral health inequities persisted across dental caries prevalence (decayed teeth [DT]) or its management (missing teeth [MT], filled teeth [FT]).

Methods: Data were from 2 population-based cross-sectional surveys of Australian adult oral health conducted in 2004-2006 (National Survey of Adult Oral Health-1 [NSAOH-1], n = 5,505) and 2017-2018 (NSAOH-2, n = 5,022). In each survey, representative samples of adults were obtained through a 3-stage, stratified sample design within metropolitan and regional areas in each state/territory. Clinical outcomes included the prevalence and mean of DT, MT, FT, and DMFT. Equivalized household income was grouped into approximately quartiles from low to high.

Results: Across all income quartiles, the mean DT and % DT >0 was higher in NSAOH-2 than in NSAOH-1. The increase in prevalence was highest in the third highest income group (prevalence difference [PD] = 8.4, from 24.1 to 32.5). Similarly, % MT >0 was lower in NSAOH-2 than in NSAOH-1 across all income groups, with the decrease most marked for the lowest income group (PD = -6.5, from 74.1 to 67.8). Across all income quartiles, % FT >0 was lower in NSAOH-2 than in NSAOH-1. The decrease was the most marked for the lowest income group (PD = -8.9, from 81.1 to 72.2).

Conclusion: The findings confirm that although oral health inequities decreased for the most extreme management outcome of dental caries (MT), inequities increased for experience of that disease (DT) and the more conservative management of dental caries (FT). For all D, M, and F components (DMFT), inequities between the lowest and highest household income groups increased from 2004-2006 to 2017-2018.

Knowledge transfer statement: This study found that social inequities in oral health (experience of untreated dental caries and missing teeth) increased between the most socially advantaged and disadvantaged groups between 2004-2006 and 2017-2018. This suggests that models of dental service provision in Australia are increasingly benefitting those who can afford and access the care and who arguably need the services less than their less socially advantaged counterparts do.