Dental Benefits of Limited Exposure to Fluoridated Water in Childhood

The effect of limited exposure to fluoridated water in childhood is of potential importance in highly-mobile modern society, but the subject has not been well-studied. This longitudinal study assessed caries experience and S. mutans proportions from fissure plaque in school-children who lived for at least the three years of the study in a non-fluoridated community (0.2 mg/L). Residence histories permitted division of the cohort into those who had lived all their lives in non-fluoridated communities, and those who had lived for some time previously in a fluoridated community. The children were aged 6-7 years at the beginning of the three-year study. Children with previous residence in the fluoridated communities developed 26.8% less caries in their permanent teeth during the study than did the children who had lived in non-fluoridated communities all their lives (p = 0.04), and had 29.8% less caries after three years (p = 0.02). Differences between the groups in S. mutans proportions from fissure plaque, sampled at six-monthly intervals throughout the study, could not be demonstrated. The dental benefits observed could not be attributed to socio-economic differences between the groups. Despite evidence that the benefits of limited ingestion of fluoridated water are topical in nature, the fact that many of the affected teeth in this study were unerupted at the time of the fluoride exposure means that pre-eruptive benefits cannot be ruled out.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66708/2/10.1177_00220345860650110801.pd

Long-term effect of xylitol chewing gum on dental caries

– About 85% ( n = 269) of the subjects who participated in the Ylivieska follow-up studies on the effect of xylitol chewing gum on dental caries during 1982–84 or 1982–85 were re-examined in 1987 for the analysis of possible long-term preventive effects. Further caries reduction was found 2 or 3 yr after the discontinuation of the use of xylitol. The effect was especially marked in girls; the reduction in caries increment in the post-use years was 60% for the 2-yr users, suggesting that more pronounced caries reduction was associated with the most regular use of xylitol. In teeth erupting during the first year of the use of xylitol gum the long-term preventive effect was greater than in other teeth. Several explanations are suggested: lasting effect of the microbiological changes in the mouth, bacterial colonization on newly erupted teeth by organisms other than S. mutatis , and/or thorough maturation of the teeth under favorable physico-chemical circumstances. The results suggest that the value of xylitol in caries prevention depends on the timing of the treatment in relation to the development of the dentitionPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75700/1/j.1600-0528.1989.tb00611.x.pd

The identification of bacteria associated with periodontal disease and dental caries by enzymatic methods

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73856/1/j.1399-302X.1986.tb00322.x.pd

A new method for chlorhexidine (CHX) determination: CHX release after application of differently concentrated CHX-containing preparations on artificial fissures

Aims of the study were (1) to establish a method for quantification of chlorhexidine (CHX) in small volumes and (2) to determine CHX release from differently concentrated CHX-containing preparations, varnishes, and a CHX gel applied on artificial fissures. CHX determination was conducted in a microplate reader using polystyrene wells. The reduced intensity of fluorescence of the microplates was used for CHX quantification. For verification of the technique, intra- and inter-assay coefficients of variation were calculated for graded series of CHX concentrations, and the lower limit of quantification (LLOQ) was determined. Additionally, artificial fissures were prepared in 50 bovine enamel samples, divided into five groups (A–E, n = 10) and stored in distilled water (7 days); A: CHX-varnish EC40; B: CHX-varnish Cervitec; C: CHX-gel Chlorhexamed; D: negative control, no CHX application; and E: CXH-diacetate standard (E1, n = 5) or CHX-digluconate (E2, n = 5) in the solution. The specimens were brushed daily, and CHX in the solution was measured. The method showed intra- and inter-assay coefficients of variation of <10 and <20%, respectively; LLOQ was 0.91–1.22 nmol/well. The cumulative CHX release (mean ± SD) during the 7 days was: EC40 (217.2 ± 41.8 nmol), CHX-gel (31.3 ± 8.5 nmol), Cervitec (18.6 ± 1.7 nmol). Groups A–C revealed a significantly higher CHX release than group D and a continuous CHX-release with the highest increase from day 0 to 7 for EC40 and the lowest for Chlorhexamed. The new method is a reliable tool to quantify CHX in small volumes. Both tested varnishes demonstrate prolonged and higher CHX release from artificial fissures than the CHX-gel tested

What is damaging the kidney in lupus nephritis?

Despite marked improvements in the survival of patients with severe lupus nephritis over the past 50 years, the rate of complete clinical remission after immune suppression therapy i