Dental Scaling and Long-Term Care Insurance Entry among Older Adults: A Nationwide Retrospective Cohort Study in South Korea

Abstract Background Preventive dental care is essential for maintaining oral health in later life. Dental scaling is a common preventive periodontal procedure; however, evidence linking it to later-life functional dependency or long-term care needs remains limited. Using nationwide claims and long-term care insurance (LTCI) records, we examined whether dental scaling is associated with subsequent LTCI entry among older adults in South Korea. Methods This retrospective cohort study used data from the Korean National Health Insurance Service Senior Cohort Database 2.0. Adults aged ≥ 65 years were classified based on the presence of at least one dental scaling claim during 2013–2014 and were followed up from 2015 to 2019. LTCI entry was defined as the first certification of grades 1–5. Fine–Gray models treat death before LTCI entry as a competing event. Sensitivity analyses included propensity score matching, inverse probability of treatment weighting, and a 1-year lag. The cumulative incidence and 5-year restricted mean time lost were estimated. Results Among the 99,218 participants, 6,987 entered the LTCI. In the fully adjusted model, dental scaling was associated with a lower sub-distribution hazard of LTCI entry (sub-distribution hazard ratio 0.69, 95% confidence interval 0.63–0.76). This trend was consistent across sensitivity analyses. The 5-year restricted mean time lost was 24.93 and 54.49 days in the scaling and no-scaling groups, respectively, indicating a lower cumulative LTCI burden of entry. Conclusions Dental scaling was consistently associated with a lower risk of subsequent LTCI. Dental scaling claims may serve as a population-level marker of preventive dental care use and the subsequent risk of LTCI entry. These findings support the clear role of preventive oral healthcare in healthy aging and long-term care strategies.