Dental Fluorosis, Dental Caries and Fluoride Exposure among 7-Year-Olds

Abstract

Mild dental fluorosis is frequently linked to fluoridated water, but discretionary fluoride sources may also be important. The aim of this study was to record age of weaning and fluoride exposure from water, toothpaste and supplements, and to relate these to the presence of caries and fluorosis in children born in 1983. In Perth (Western Australia) 14 school classes were selected. The 350 children (mean age 7.5 years) ultimately included gave fluoride exposure data for the period birth to 4 years of age. Caries (DMFT, WHO criteria, no radiographs) and dental fluorosis (TF index, dry permanent incisors) were registered clinically. Most (89%) children had lived at least 2.5 years in a fluoridated area. Supplement use was minimal and unrelated to caries or fluorosis. Mean age of weaning of those who had been breast-fed was 7.7 months; by 9 months, 74% had been weaned. Eighty-five percent liked toothpaste, 60.7% had swallowed it, and the mean age of starting to use it was 1.5 (SD 0.96) years. Caries prevalence was 0.1 and mean DMFT was 0.13. The prevalence of fluorosis was 0.48; 63% of fluorosis was TF score 1. Residence in a fluoridated area for ≥2.5 of the first 4 years of life had an odds ratio (OR) of 4.9 for fluorosis. Weaning before 9 months of age, swallowing toothpaste and liking toothpaste were also statistically significant risk factors. Major risk factors for more severe fluorosis (TF ≥2) were early weaning and swallowing toothpaste (ORs 2.77 and 2.64, respectively). Residence in a fluoridated area (OR 2.2) was not a statistically significant risk factor. These findings confirm a high prevalence of mild fluorosis among children who have been exposed to fluoride in their earliest years. High attributable proportions associated with age of weaning and toothpaste use suggest that elimination of fluoride from formula and a reduced fluoride concentration in toothpaste would contribute significantly to reducing the prevalence of more visible fluorosis.

Prevalence of caries and developmental defects of enamel in 9-10 year old children living in areas in Brazil with differing water fluoride histories

“…That these are the defects associated with fluoride may be suggested by findings that a higher prevalence of diffuse defects is associated with the use of fluoride supplements, 5,25 the use of fluoride toothpaste 25 and the use of fluoride dentifrices at an early age in optimally fluoridated areas. 20,23,41,42 Fluoride supplements are not used in Brazil but since 1988 about 90% of commercially available dentifrices in Brazil has been fluoridated 43 with most containing standard (1000 ppm) fluoride ion concentrations as directed by the Ministry of Health.…”

Developmental Enamel Defects in Children with Different Fluoride Supplementation – a Follow–Up Study

“…During the past decade numerous studies [Burt, 1992;Pendrys and Stamm, 1990;Burt, 1987, 1992;Riordan, 1993] reported on an increasing frequency of developmental enamel defects, both in fluoridated and nonfluoridated areas. However, large differences in the prevalence of developmental enamel defects may be recorded depending on the examiner and the type of index used [Pendrys and Katz, 1989;Ellwood et al, 1994;Rozier, 1994].…”

Socio-Demographic Features and Fluoride Technologies Contributing to Higher Fluorosis Scores in Permanent Teeth of Canadian Children

“…Various studies have shown that increased frequency and/or severity of dental fluorosis are associated with residence in a location with fluoridated water supplies, increased use of dietary fluoride supplements and other fluoride modalities, use of baby formula (in particular when formula was not ready to use and was reconstituted with fluoridated water), an early age of initiating tooth brushing (in particular when the child could be presumed to lack supervision to spit toothpaste rather than swallow it), and higher family SES [Osuji et al, 1988;Szpunar and Burt, 1988;Pendrys and Katz, 1998;Riordan, 1993;Pendrys et al, 1994;Clark et al, 1994;Lalumandier and Rozier, 1995]. With various modifying roles and magnitudes for specific factors, these trends suggest that increased fluoride availability to the maturing enamel during certain critical windows has led to more prevalent dental fluorosis in North America [Rozier, 1999].…”