Daily Archives: May 2, 2015

Nano Silver Fluoride Effective for Preventing Caries

Burns J, Hollands K. Nano Silver Fluoride for preventing caries. Evidence-Based Dentistry. 2015 Apr;16(1):8-9. doi: 10.1038/sj.ebd.6401073.

Design: Randomised controlled trial, double blind, in a community setting.

Intervention: School children with active caries in primary teeth and no pulpal exposure, fistula or decay in permanent teeth were chosen. Caries and unsupported enamel were left as found and cotton wool rolls were used for isolation. Two drops of NSF or one drop of water were applied to the tooth with a microbrush for two minutes, once in a 12-month period.

Outcome measure: At one week, five months and 12 months the presence of active caries, as classified using International Caries Detection and Assessment System (ICDAS II) criteria, was measured. If a blunt probe easily penetrated dentine with light force, active caries was recorded and taken to be a failure.

Results: One hundred and thirty primary teeth in 60 children with a mean age of 6.31 (± 0.60) were randomised. Sixty-three teeth were in the NSF group and 67 in the control group. After one week there were no losses, at the five-month follow up eight teeth were lost from the NSF group due to exfoliation or extraction and five from the control group. At twelve months a further five teeth were lost from the NSF group and 13 from the control group.At the one week follow up there was a 19% failure rate in the NSF group compared to 100% in the control group. At the five month recall this was 27.3% NSF compared to 72.6% water and at the final recall there was a 33.3% NSF failure rate and 65.3% control failure rate. The preventative fraction at this point was 50% and the NNT 3.12. All were statistically significant results (p= <0.05).

Conclusions: The annual application of NSF solution was more effective in hardening and arresting dentine caries in primary teeth than the placebo. The effectiveness of NSF was found to be similar to silver diamine fluoride when applied once a year, but did not stain the dental tissue black and had no metallic taste. The application is simple, does not require a clinical setting and is inexpensive. NSF was demonstrated to be effective in arresting caries in children in poor communities, but further studies are required to investigate alternative protocols and for use in tooth sensitivity and root caries.

Drinking Water Fluoride a Causative Factor of Chronic Kidney Diseases, Sri Lanka

Dharmaratne RW. Fluoride in drinking water and diet: the causative factor of chronic kidney diseases in the North Central Province of Sri Lanka. Environmental Health and Preventive Medicine. 2015 Apr 28.

A significant number of people in the North Central Province of Sri Lanka suffer from chronic kidney diseases (CKD), and the author revisits existing literature related to CKD to find its causative factor. There is a direct connection between high fluoride levels in drinking water and kidney disease, and there are unhealthy levels of fluoride in the groundwater in Sri Lanka’s CKD-affected areas. Based on the following observations, the author believes with confidence that excess fluoride in drinking water and in the locally grown food in the affected areas are the culprits of CKD in Sri Lanka. Fluoride excretion rate is considerably lower in children than adults, leading to renal damage of children living in areas with high fluoride. Adults who had renal damage due to fluoride in childhood are vulnerable to CKD with continued consumption of water from the same source. Patients with chronic renal insufficiency are at an increased risk of chronic fluoride toxicity. High content of fluoride in groundwater paves the way to excess fluoride in local food crops, consequently adding more fluoride to the systems of the consumers. People who work outdoors for prolonged periods consume excess water and tea, and are subjected to additional doses of fluoride in their system. In the mid-1980s, the increase in water table levels of the affected areas due to new irrigation projects paved the way to adding more fluorides to their system through drinking water and locally grown foods.

Click here for paper (Open Access).

Acanthamoeba in Drinking Water Reservoirs, Taiwan

Kao PM; Hsu TK; Liu JH; Chang HY; Ji WT; Tzeng KJ; Huang SW; Huang YL; Seasonal distribution of potentially pathogenic Acanthamoeba species from drinking water reservoirs in Taiwan. Environmental Science And Pollution Research International. 2015 Mar; Vol. 22 (5), pp. 3766-73. 2014 Sep 30.

In order to detect the presence/absence of Acanthamoeba along with geographical variations, water quality variations and seasonal change of Acanthamoeba in Taiwan was investigated by 18S ribosomal RNA (rRNA) gene TaqMan quantitative real-time PCR. Samples were collected quarterly at 19 drinking water reservoir sites from November 2012 to August 2013. Acanthamoeba was detected in 39.5 % (30/76) of the water sample, and the detection rate was 63.2 % (12/19) from samples collected in autumn. The average concentration of Acanthamoeba was 3.59 × 10(4) copies/L. For geographic distribution, the detection rate for Acanthamoeba at the northern region was higher than the central and southern regions in all seasons. Results of Spearman rank test revealed that heterotrophic plate count (HPC) had a negative correlation (R = -0.502), while dissolved oxygen (DO) had a positive correlation (R = 0.463) in summer. Significant differences were found only between the presence/absence of Acanthamoeba and HPC in summer (Mann-Whitney U test, P < 0.05). T2 and T4 genotypes of Acanthamoeba were identified, and T4 was the most commonly identified Acanthamoeba genotypes. The presence of Acanthamoeba in reservoirs presented a potential public health threat and should be further examined.