Original Paper Caries Res 2001;35:95–105 Received: July 4, 2000 Accepted after revision: November 13, 2000 Tooth-Surface Progression and Reversal Changes in Fluoridated and No-Longer- Fluoridated Communities over a 3-Year Period Fax +41 61 306 12 34 E-Mail karger@karger.ch www.karger.com  2001 S. Karger AG, Basel 0008–6568/01/0352–0095 $17.50/0 Accessible online at: www.karger.com/journals/cre Dr. Gerardo Maupomé Center for Health Research 3800 N. Interstate Avenue, Portland, OR 97227-1110 (USA) Tel. +1 503 335 6625, Fax +1 503 335 2428 E-Mail gerardo.maupome@kpchr.org Gerardo Maupomé a, d , Jay D. Shulman b , D. Christopher Clark d , Steven M. Levy c , Jonathan Berkowitz e a Center For Health Research, Portland, Oreg., USA; b Baylor College of Dentistry, Dallas, Tex., USA; c College of Dentistry, University of Iowa, Iowa City, Iowa, USA; d Faculty of Dentistry and e Faculty of Commerce and Business Administration, University of British Columbia, Vancouver, B.C., Canada Abstract Objective: To compare permanent tooth surface-specific progression/reversal changes between fluoridation-end- ed (F-E) and still-fluoridated (S-F) communities in British Columbia, Canada, over a 3-year period. Methods: D1D2MFS examinations were contrasted for 2,964 schoolchildren in 1993/94 (grades 2, 3, 8 and 9) and 1996/97 (grades 5, 6, 11 and 12). Generalized Estimating Equation (GEE) models explored the relation between progression/reversal changes and fluoridation status, age, gender, socioeconomic status, and dietary/fluoride histories. Results: Within a scenario of low levels of caries overall, few children had multiple surfaces pro- gressing. At least one smooth surface progressed in 31.4% of subjects; at least one pit-and-fissure (PF) sur- face progressed in 43.1% of subjects. At least one smooth surface reverted in 89% of subjects who had re- versible stages; at least one PF surface reverted in 23.8% of subjects who had reversible stages. GEE (smooth) in- dicated that odds ratios of progression were twice as Key Words Canada · Caries progression/reversal · Children · Epidemiologic survey · Fluoridation cessation · Water fluoridation Copyright © 2001 S. Karger AG, Basel The current decline in caries prevalence for many popu- lations in industrialized countries is associated with a slow- er rate of carious lesion progression in general. This has made accurate appraisal of the progression rate more im- portant from clinical and financial points of view. From a treatment needs perspective, the Canadian public is becom- ing more heterogeneous [Abramson and Heimann, 1997]. large in the F-E site compared to the S-F site, and slight- ly increased in older participants and in participants ex- posed to more fluoride technologies. GEE (PF) also indi- cated that progression was slightly more common in the F-E site; more frequent snacking and lower parental ed- ucational attainment had modest associations with in- creased progression in PF surfaces. For the two types of surfaces, GEE models demonstrated that unerupted sur- faces were less likely to progress than sound surfaces. No associations were found between reversals and inde- pendent variables. Conclusion: Progressions were found to be weakly linked to socio-demographic factors; base- line surface statuses were better predictors of progres- sion. Using the current definitions for disease transi- tions, F-E communities had more frequent progressions than a S-F community.