potassium-fluoride and Fluorosis--Dental

Although a 40 per cent solution of silver fluoride would be expected to contain 6 per cent fluoride (60,000 ppm), F-levels of 100,000 ppm and 120,000 ppm were found in 14 commercial samples analysed at The University of Western Australia in 1993 and 1994. To determine whether F-levels in 40 per cent AgF preparations have remained high, the present investigation was aimed at analysing different batches of commercial preparations obtained more recently. Fluoride ion analysis was carried out on 24 AgF samples using the Ion-Selective Electrode technique. Independent analyses of the same samples were carried out by a private chemical testing laboratory (Genalysis). Ten samples supplied by Agson Chemical Export were found to contain between 75,000 and 100,000 ppm F-: Genalysis reported 80,000 to 120,000 ppm. Fourteen samples supplied by Southern Dental Industries were found to contain between 70,000 and 120,000 ppm F-; Genalysis reported 88,000 to 108,000 ppm F-. These results confirm significantly higher than expected F-levels (ANOVA p < 0.05) in commercial preparations of 40 per cent AgF. The solutions tested were found to contain a mixture of ammonium fluoride, sodium or potassium fluoride, and silver fluoride. The additional presence of silver difluoride and hydrofluoric acid resulting from the manufacturing process has been suggested as an explanation for the much higher than expected levels of fluoride ion. In view of possible toxicity of 40 per cent AgF in young children, it is concluded that such a highly concentrated solution should not be used clinically; instead, lower strength AgF solutions should be investigated for their efficacy in caries treatment.

Topics: Ammonium Compounds; Analysis of Variance; Cariostatic Agents; Child; Contraindications; Fluorides; Fluorides, Topical; Fluorosis, Dental; Humans; Hydrofluoric Acid; Ion-Selective Electrodes; Potassium Compounds; Quaternary Ammonium Compounds; Silver Compounds; Sodium Fluoride; Spectrum Analysis

The caries prevalence in a multi-stage probability sample of 18,786 children representative of all French children 6-15 years of age was studied in 1991 and compared with the results of a similar survey made in 1987. A significant decline in dental caries in France became evident. This decline, observed in primary as well as in permanent teeth, was of variable magnitude among the different age groups. At the age of 6, 48.6% of the children were totally caries-free in 1991. At the age of 12, the DMFT and DMFS indices were 2.59 and 4.72, respectively, representing a corresponding decrease of 38% and 37%. In 1991, more caries-affected teeth or surfaces were filled, whereas fewer caries-affected teeth or surfaces were untreated. Females and children living in rural areas had a higher caries prevalence in both surveys. Pit-and-fissure lesions were the predominant caries types. Dental fluorosis was very uncommon; 96.1% of the 18,786 children examined in 1991 were totally free of any such lesions. Average plaque and calculus indices were similar in 1987 and in 1991, but a decrease of 25% was observed in the average gingival indices. Although the relative contributions of various preventive factors leading to this caries reduction are not clear, it should be noted that use of fluoridated salt (250 mg/kg KF) started in January, 1987. The sale of fluoridated dentifrices and the use of fluoride tablets and sugar substitutes increased during the period from 1987 to 1991.

Topics: Adolescent; Age Distribution; Analysis of Variance; Child; Dental Caries; Dental Fissures; Dental Plaque Index; DMF Index; Female; Fluorides; Fluorosis, Dental; France; Humans; Male; Oral Hygiene Index; Periodontal Index; Potassium Compounds; Prevalence; Sodium Chloride; Tooth, Deciduous