An attempt to explain why Tanzanian children drinking water containing 0.2 or 3.6 mg fluoride per liter exhibit a similar level of dental fluorosis

Abstract

The aim of this study was to identify factors that might explain the similar level of prevalence and severity of dental fluorosis in two neighboring areas in Tanzania: Kibosho; 0.2 mg fluoride/l, n = 96 and Arusha; 3.6 mg fluoride/l in drinking water, n = 80. Subjects aged 8-16 years were examined for dental fluorosis using the Thylstrup and Fejerskov Index (TFI). Based on the score on the upper left central incisor, the prevalence was not significantly different between the communities (TFI > or = 1). The severity, however, was significantly higher in Arusha. The areas had different food habits, e.g., type of weaning food used, and the use of magadi, a fluoride containing salt. In Arusha, 99% of the children had been given lishe, which is a magadi-free weaning food. Conversely in Kibosho, 61% used lishe while 39% used the magadi-containing weaning food kiborou. Magadi was used as food tenderizer in 'adult food' by 98% in Kibosho and 45% in Arusha. Residential area and use of magadi explained 5% of the variance in TFI scores in inter-area analyses. In intra-area analyses, weaning food in Kibosho and use of magadi in Arusha had a significant effect, but the total explained variance was only 5 and 4%, respectively. Apart from fluoride in the drinking water, other sources of fluoride such as use of magadi in weaning food (kiborou) and in the adult food may partly explain the high prevalence and severity of dental fluorosis in the community with 0.2 mg fluoride per liter in the drinking water.

Fluoride: A toxic or therapeutic agent in the treatment of osteoporosis?

“…It might be speculated if the intake of calcium and/or vitamin D has been marginal or deficient in these populations. This would result in insufficient calcification of the osteoid [29,30]. It has been reported that workers with such exposure had better dental status than populations without fluoride exposure, although exposed young children may suffer from mottled teeth [25,30].…”

Caries experience and caries predictors – a study of Tanzanian children consuming drinking water with different fluoride concentrations

“…Children from two areas in the municipality of Arusha (Arusha and Arusha Meru) and from Moshi and Kibosho in the Kilimanjaro region were examined. Arusha town has approximately 135,000 inhabitants and is served by a municipal water supply containing 3.6 mg F/l in the drinking water [1,3,34]. Subjects from Arusha Meru are mostly ethnic Asians, while the inhabitants in Arusha and in both districts of the Kilimanjaro region are of African extraction.…”

“…The corresponding median scores in the high-F area were 5.0 in Arusha and 3.0 in Arusha Meru, i.e., with a significantly different distribution (P<0.001, Mann-Whitney U test). The findings related to dental fluorosis have been reported previously [1,2,3]. Re-examination for carious lesions was carried out on the lower right first molars in 32 children after 1 week.…”

“…As the severity on a maxillary central incisor has been shown not to deviate from the 1 The instruments used were sterilised in autoclaves at 115°C for 60 min (at 10 psi), then wrapped in sterile cloth and packed in sterile drums for transport to the examination sites.…”

“…Trona, an F-contaminated salt (Na 2 CO 3 NaHCO 3 2H 2 O), is frequently used in Tanzania [1,2,15,35,38], especially in rural areas [2]. Trona and fluoridated salt are both used in food preparation, and their F content may have a similar cariostatic effect [37].…”