Inequalities in orthodontic outcomes in England: Treatment utilisation, subjective and normative need

Objective: To investigate inequalities in three aspects of access to orthodontic care: uptake of orthodontic treatment, normative need and subjective need in England. Methods: We used data from two surveys in England: 12 and 15-year-olds from the 2013 Child Dental Health Survey (CDHS 2013) and 12-year-olds from the 2008/2009 NHS Dental Epidemiology Programme for England (NDEP 2008/2009). Summary variables representing orthodontic status were calculated. Two regression-based summary measures of inequalities were used to investigate the relationship between deprivation level and orthodontic outcomes: Slope and Relative indices of Inequality. Results: There were significant absolute and relative inequalities in uptake of orthodontic treatment. The least deprived were 1.9 times more likely to have received orthodontic treatment compared to the most deprived in both surveys. Normative need was not associated with deprivation in either the analyses of CDHS 2013 (SII= 0.03, 95% CI:-0.04, 0.1; RII=1.06, 95% CI: 0.91, 1.24) or the NDEP 2007/2008 (SII= 0.03, 95% CI:-0.02, 0.07; RII=1.06, 95% CI: 0.96, 1.18). There was greater willingness to have teeth straightened in more deprived children from CDHS 2013 (SII=-0.09, 95% CI:-0.16,-0.03; RII=0.85, 95% CI: 0.75, 0.96) but not in NDEP 2007/2008 (SII=0.03, 95% CI: 0, 0.06; RII=1.07, 95% CI: 0.99, 1.15). Conclusions: Being deprived was associated with lower uptake of orthodontic treatment. Normative need was not related to deprivation. The association between deprivation and subjective need was only partly established, with poorer children showing a greater desire to have their teeth straightened in one survey.