Independent and Additive Effects of Different Sources of Fluoride and Dental Fluorosis.
OBJECTIVE
To investigate the contribution of different sources of fluoride related to dental fluorosis.


METHODS
This population-based, matched, case-control study (67 pairs) used a representative sample of 271 schoolchildren. Dental fluorosis was measured using Dean's index. Children's caregivers were interviewed about nine risk factors. Data were analyzed using conditional logistic regression.


RESULTS
The prevalence of questionable cases was 18.8 percent, and the prevalence of very mild, mild, or moderate cases of dental fluorosis was 11.5 percent, with no severe case. Age of start of toothbrushing, drinking water from wells, frequency of toothbrushing, type of tooth-paste, standard/ children's mouthrinse usage, and fluoride supplements were not significant (P>0.15). Drinking water from wells and using supplements were underpowered (N less than six). Children who frequently ate toothpaste had an odds ratio of 5.56 (95% confidence interval (CI) 1.75 to 17.73) times more fluorosis; those applying toothpaste to cover the bristles had 5.55 times more fluorosis (95% CI 1.44 to 21.42); and those using an adult size toothbrush had 3.17 times more flurosis (95% CI 1.15 to 8.71). There was a significant additive interaction (P<0.01).


CONCLUSIONS
In a community with water fluoridation, the factors associated with dental fluorosis are intentional toothpaste ingestion and tooth-paste applied on the whole toothbrush.
Department of Preventive and Social Dentistry, Faculty of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil. roger.keller@ufrgs.br.
Roger Keller
RK
Celeste
Department of Preventive and Social Dentistry, Faculty of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
Patricia Blaya
PB
Luz
D001938:Brazil / Q000453:epidemiology; D002327:Cariostatic Agents / Q000008:administration & dosage / Q000009:adverse effects; D016022:Case-Control Studies; D002648:Child; D003731:Dental Caries / Q000453:epidemiology* / Q000209:etiology; D003753:Dental Health Surveys; D005260:Female; D005457:Fluoridation / Q000009:adverse effects; D005459:Fluorides / Q000008:administration & dosage / Q000009:adverse effects; D009050:Fluorosis, Dental / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D016015:Logistic Models; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D014099:Toothbrushing; D014100:Toothpastes / Q000009:adverse effects
D002327:Cariostatic Agents; D014100:Toothpastes; D005459:Fluorides