Time Until Tooth Loss Among Pre-Elderly Southern Thais under Universal Coverage: A Retrospective Cohort Study
Abstract
Objective: This study used dental data to determine the time until tooth loss and its associated factors among pre-elderly individuals aged 45–59 in Southern Thailand.
Material and Methods: A retrospective cohort study was conducted using dental data from 2019 to 2023. The study included individuals under the Universal Health Coverage Scheme who received dental examinations and follow-up care. Tooth loss was defined as permanent tooth extraction (excluding impacted third molars). Data were censored if no extraction occurred by the end of the study or if participants were lost to follow-up. Cox proportional hazards models and Kaplan-Meier analyses were applied with statistical significance at p-value<0.05. Time-varying covariates were also examined.
Results: A total of 4,177 participants were included; 1,582 (37.9%) experienced tooth loss. The overall median time until tooth loss was 40.0 months (95% confidence interval [CI]: 37.9–42.3). Individuals with fewer than 20 teeth, ≥3 decayed teeth, no dental scaling, and aged 55–59 had a shorter median time until tooth loss. Multivariable analysis showed that lack of dental scaling (Hazard rate [HR] 1.53; 95% CI: 1.29–1.81) and ≥3 decayed teeth (HR 1.30; 95% CI: 1.14–1.49) were associated with earlier tooth loss.
Conclusion: Tooth loss among pre-elderly Thais occurred earlier in those with untreated caries and without dental scaling. These findings highlight the critical importance of timely caries treatment and regular scaling in preserving teeth for long-term function.
Keywords
Full Text:
PDFReferences
Kassebaum NJ, Bernabé E, Dahiya M, Bhandari B, Murray CJL, Marcenes W. global burden of severe tooth loss: a systematic review and meta-analysis. J Dent Res 2014;93:20S-8.
Institute for Health Metrics and Evaluation (IHME). Global burden of disease study 2021 (GBD 2021) results. [homepage on the Internet]. Seattle: IHME; 2023 [cited 2025 Jun 16]. Available from: https://vizhub.healthdata.org/gbd-results/
Bureau of Dental Health. Report of the 9th national health examination survey, Thailand 2023. Nonthaburi: Ministry of Public Health; 2024;p.404.
Department of Older Persons. National Agenda Driving Measures for Aging Society (Revised Edition). Bangkok: Ministry of Social Development and Human Security; 2019.
Office of the Permanent Secretary, Ministry of Public Health. Standard health data collection and submission manual, fiscal year 2021 version 2.4. Nonthaburi: Ministry of Public Health; 2021.
National Health Security Office (NHSO). User’s guide to health insurance benefits: dental benefits [homepage on the Internet]. Bangkok: NHSO; 2025. [cited 2025 Aug 22]. Available from: https://www.nhso.go.th/th/2024-08-22-03-33-7
National Health Security Office (NHSO). Population classified by entitlement and age group [homepage on the Internet]. Bangkok: NHSO; 2025. [cited 2025 Aug 22]. Available from: https://ucinfo.nhso.go.th/ucinfo
Rubinstein LV, Gail MH, Santner TJ. Planning the duration of a comparative clinical trial with loss to follow-up and a period of continued observation. J Chronic Dis 1981;34:469-79.
Jirachaiprasit N, Hintao J, Pithpornchaiyakul W. Time until tooth loss among the pre-elderly and related factors: a study from 43-File standard datasets in a community hospital, Surin province. Proceedings of the 5th Science Technology and Innovation Conference 2024 [homepage on the Internet]. Chiang Mai: Maejo University; 2024 [cited 2025 7 July]. Available from: https://sciencebase.mju.ac.th/csti2024/Proceedings2024/Proceedings2024ER.pdf
R Core Team. R: A language and environment for statistical computing. Vienna: R Foundation for Statistical Computing; 2023.
Chen X, Clark JJJ, Naorungroj S. Length of tooth survival in older adults with complex medical, functional and dental backgrounds. J Am Dent Assoc 2012;143:566-78.
National Health Security Office (NHSO). Management of health promotion and disease prevention services for fiscal year 2023 [homepage on the Internet]. Bangkok: NHSO; 2022. [cited 2025 Aug 22]. Available from: http://www.sshos.go.th/wp-content/uploads/2022/09/PP-Fee-shedule_66.pdf
Lee G, Koh S, Kim N. Regular dental scaling associated with decreased tooth loss in the middle-aged and elderly in Korea: A 3-year prospective longitudinal study. Indian J Dent Res 2019;30:231-7.
Refbacks
- There are currently no refbacks.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.