Previous studies have indicated that married people are generally healthier than unmarried people, with lower mortality rates. Most work in this area has employed cross-sectional data, and few studies have examined change in marital status from married to unmarried as a potential social ecological determinant of dental health behavior. Here we used longitudinal data to examine change in dental behavior over time following marital status change, and to explore whether self-reported gender may play a modifying role in any behavioral change. Employing panel data from the Healthy Retirement Study (1996-2018) to follow all individuals who entered the study in married/partnered status, and using both two-way fixed effects and group-time average difference-in-difference models, we analyzed the association between any change in marital status and dental care use, compared to individuals who remained married. All analyses were stratified by gender. Both types of difference-in-difference analyses indicated that both widowhood and divorce were associated with a decrease in dental care use in both genders. Divorced men saw the greatest decrease in dental care use. We found gender had a moderating effect on strength of association in all analyses. This research suggests that any change in marital status from married to unmarried has a detrimental effect on dental health behavior for both genders. Future research might investigate other potential barriers to dental care access these populations might face, in order to develop effective interventions.