S1 Data -

Background
There is an intersection between oral and mental health though the studies on these intersections are few. This study investigated associations between self-reported oral health problems, quality of oral health, and depression and general anxiety among adolescents and adults in Nigeria; and analysed the moderating effects of resilience and self-esteem on these associations.
Methods
In this secondary analysis, data were extracted from the database of an online survey conducted among participants 13 years and older and living in Nigeria about their self-reported psychological wellbeing. The data was collected between September and October 2020. Dependent variables were self-reported presence of oral health problems (yes/no) and self-reported quality of oral health (using a five-item scale ranging from “very good” to “very poor”). Independent variables were depressive and anxiety symptoms. Moderating factors evaluated were resilience and self-esteem. Multivariable logistic regression analysis was used to determine the associations between the dependent and independent variables after adjusting for confounders (age, sex, employment status and educational status). A path analysis was conducted to determine the moderating effects of self-esteem and resilience on associations between dependent and independent variables.
Results
We extracted data for 2,757 adolescents and adults aged 13 to 62 years, of which 2,062 (74.8%) reported having oral health problems and 925 (33.6%) reported poor quality of oral health. Higher levels of depressive symptoms were significantly associated with higher odds of oral health problems (AOR: 1.07; 95% CI: 1.04–1.10; p<0.001). Higher levels of depressive symptoms (AOR: 1.05; 95% CI: 1.03–1.07; p<0.001), and higher levels of anxiety symptoms (AOR: 1.07; 95% CI: 1.04–1.11; p<0.001) were significantly associated with poor quality of oral health. Resilience significantly moderated the association between anxiety symptoms and oral health problems (AOR = -0.004; 95% CI: -0.006 –-0.001; p = 0.002).
Conclusion
Depression may be a risk indicator for self-reported oral health problems, while depression and anxiety appear to be risk indicators for self-reported poor quality of oral health. These factors could be included as confounders in future studies on oral health problems and quality of oral health among adolescents and adults in Nigeria.