Fusao Nishikawara

Evaluation of risk factors for dental caries from 6 to 8 years old children

The aim of this study is to evaluate the risk factors for dental caries in young children in Japan. We studied 645 children attending 13 of 30 elementary schools in two areas in Japan. Total salivary level of mutans streptococci and lactobacilli were evaluated at pre-school medical check-ups. Other factors we evaluated included use of fluoride containing dentifrices, administration of fluoride varnish in a private dental office, having regular check-ups, use of mouthwash with fluoride, and daily intake of sweet juice or snacks. Oral examinations were carried out at annual medical check-ups with 2.5 years follow-up and finally 585 children were analyzed. By multivariate logistic regression analysis, only three factors; gender, salivary levels of mutans streptococci and the presence or absence of dental caries in deciduous teeth had a statistically significant correlation with the incidence of dental caries after 2.5 years of follow-up. At age 8, odds ratios were 1.821 for female gender, 1.259 for mutans streptococci (log10 cfu/ml) and 2.262 for dental caries in deciduous teeth. Although the prevalence of dental caries has declined in Japan, mutans streptococci remain a risk factor.

A randomized controlled trial by the 3DS for dental caries

Abstract The aim of this study is to evaluate the povidone-iodine for the suppression of oral cariogenic bacteria and compare its effects to that of fluoride in children. We carried out a randomized controlled trial to compare the effects of povidone-iodine to those for sodium fluoride. Pre-school children (n=210) with more than 10 5 cfu/m l mutans streptococci in their stimulated saliva were randomly sampled and randomly allocated into three groups. We planned the preventive program by 3DS (Dental Drag Delivery System). The groups that provided preventive programs were the povidone-iodine group (n=70) and the sodium fluoride group (n=70). A control group (n=70) received no intervention. Povidone-iodine or sodium fluoride was applied to the tooth surface using custom made trays. Subsequent home care was obligatory for one month. After one month, the salivary levels of mutans streptococci were low level when compared to the based data. However the difference in salivary levels of mutans streptococci among groups was not statistically significant when comparing the povidone-iodine group with the sodium fluoride group ( P =0.625). After 2.5 years follow up, differences in incidence of new dental caries among the three groups were not statistically significant ( P =0.583). Clinical application of anti-microbial drugs may be effective, but only a single intervention is not sufficient to reduce the incidence of new dental caries.

Fluoride-containing mouthrinses in three European countries

The caries-preventive effect of fluoride is well known. The widespread use of fluoride-containing toothpastes and mouthrinses has been recommended to reduce dental caries. Many kinds of fluoride containing toothpastes are available in Japan. However, only two kinds of mouthrinses which contain fluoride are comically available. The aim of this study was to investigate the current status of fluoride-containing mouthrinses on the market in three European countries. Fluoride-containing mouthrinses were purchased from retail outlets in Athens, Amsterdam and Geneva. The labels of ingredients were studied to determine the type and concentration of fluoride. Most of the mouthrinses contained sodium fluoride (90%); some contained stannous fluoride (5%) or potassium fluoride (7%). The concentrations of fluoride ranged from 100 ppm to 500 ppm.

Fluoride-containing toothpastes available in two European countries

The caries-preventive effect of fluoride is well known. The widespread use of fluoride-containing toothpastes and mouthrinses has been recommended to reduce dental caries. Many kinds of fluoride-containing toothpastes are available in Japan. The aim of this study was to investigate the current status of fluoride-containing toothpastes on the market in two European countries. Fluoride-containing toothpastes were purchased from retail outlets in Cardiff, United Kingdom, and Frankfurt, Germany. The ingredients labels were studied to determine the type and concentration of fluoride. Most of the toothpastes contained sodium fluoride (56.4%); some contained monofluoroacetic sodium (31.7%), stearyl trihydroxyethyl propylenediamine dihydrofluoride (1.0%), aluminium fluoride (1.0%), stannous fluoride (2.0%), or amine fluoride (5.0%). The concentration of fluoride in these products ranged from 800 to 1,500 ppm.

Controlling cariogenic bacteria by the regular check-up system

Abstract Regular check-ups are important for reducing the risk factors of dental caries. Through regular check-ups, clinicians empirically know that the incidence of the new dental caries was suppressed. However, the effects of the regular check-up system have not been thoroughly evaluated. Our primary concern was to evaluate the efficacy of the regular check-up system with professional preventive care for preventing dental caries. In this study, we evaluated attitudes toward regular check-ups. Five hundred and thirteen patients who visited one dental office in Japan from 1981 to 2000 and who were under 12 on the first visit were examined for dental caries, salivary mutans streptococci, and Lactobacilli to obtain baseline values and the values for the more recent visit analyzed in this study. Salivary mutans streptococci and Lactobacilli were counted using Dentocult SM and Dentocult LB. Most of the risk factors, particularly the salivary levels of the mutans streptococci, were reduced by regular check-ups in this study. There was a greater risk reduction in particular for the salivary levels of mutans streptococci in patients undertaking regular check-ups. Reduced salivary levels of Lactobacilli were also observed. However, the changes between the groups in the attitude toward regular check-ups were not statistically significant. This result indicates that most of the risk factors investigated in this study could be reduced by regular check-ups, particularly the levels of mutans streptococci, which has been suggested to be a strong etiology of dental caries.