Effects of Fluoridated Drinking Water on Dental Caries in Australian Adults

• Published in: Journal of dental research Vol. 92; no. 4; pp. 376 - 382
• Main Authors: Slade, G.D., Sanders, A.E., Do, L., Roberts-Thomson, K., Spencer, A.J.
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA SAGE Publications 01.04.2013; SAGE PUBLICATIONS, INC
• Subjects: Adolescent; Adult; Age; Age Factors; Aged; Australia - epidemiology; Cariostatic Agents - administration & dosage; Clinical trials; Cohort Studies; Dental caries; Dental Caries - epidemiology; Dental Caries - prevention & control; Dentistry; Disease prevention; DMF Index; Drinking water; Female; Fluoridation; Fluorides; Fluorides - administration & dosage; Humans; Longitudinal Studies; Male; Middle Aged; Oral hygiene; Population; Public health; Questionnaires; Regression analysis; Sensitivity analysis; Studies; Teeth; Young Adult; Australia; New Zealand; United States > US; DMF Index; community water fluoridation; health surveys; adult; cohort effect
• ISSN: 0022-0345; 1544-0591
• DOI: 10.1177/0022034513481190

Systematic reviews produce conflicting conclusions regarding dental caries-preventive effects of water fluoridation in adults. The authors investigated the relationship using data from the nationally representative 2004−2006 Australian National Survey of Adult Oral Health. Effects were compared between the pre-fluoridation cohort born before 1960 (n = 2,270) and the cohort born between 1960 and 1990 (n = 1,509), when widespread implementation of fluoridation increased population coverage from < 1% to 67%. Residential history questionnaires determined the percentage of each person’s lifetime exposed to fluoridated water. Examiners recorded decayed, missing, and filled teeth (DMF-Teeth) and decayed and filled tooth surfaces (DF-Surfaces). Socio-demographic and preventive dental behaviors were included in multivariable least-squares regression models adjusted for potential confounding. In fully adjusted models, > 75% of lifetime exposure to fluoridation relative to < 25% of lifetime exposure was associated with 11% and 10% fewer DMF-Teeth in the pre-1960 (p < .0001) and 1960–1990 cohorts (p = .018), respectively. Corresponding reductions in DF-Surfaces were 30% (p < .001) and 21% (p < .001). Findings for intermediate fluoridation exposure suggested a dose-response relationship. Results were consistent in sensitivity analyses accounting for missing data. In this nationally representative sample of Australian adults, caries-preventive effects of water fluoridation were at least as great in adults born before widespread implementation of fluoridation as after widespread implementation of fluoridation.