Rehardening of acid-softened enamel and prevention of enamel softening through CO(2) laser irradiation

Objectives: The aims of the present study were to investigate whether irradiation with a CO(2) laser could prevent surface softening (i) in sound and (ii) in already softened enamel in vitro. Methods: 130 human enamel samples were obtained and polished with silicon carbide papers. They were divided into 10 groups (n = 13) receiving 5 different surface treatments: laser irradiation (L), fluoride (AmF/NaF gel) application (F), laser prior to fluoride (LF), fluoride prior to laser (FL), non-treated control (C); and submitted to 2 different procedures: half of the groups was acid-softened before surface treatment and the other half after. Immersion in 1% citric acid was the acid challenge. Surface microhardness (SMH) was measured at baseline, after softening and after treatment. Additionally, fluoride uptake in the enamel was quantified. The data were statistically analysed by two-way repeated measurements ANOVA and post hoc comparisons at 5% significance level. Results: When softening was performed either before or after laser treatment, the L group presented at the end of the experiments SMH means that were not significantly different from baseline (p = 0.8432, p = 0.4620). Treatment after softening resulted for all laser groups in statistically significant increase in SMH means as compared to values after softening (p < 0.0001). Enamel fluoride uptake was significantly higher for combined laser-fluoride treatment than in control (p < 0.0001). Conclusion: Irradiation of dental enamel with a CO(2) laser at 0.3J/cm(2) (5 mu s, 226 Hz) not only significantly decreased erosive mineral loss (97%) but also rehardened previously softened enamel in vitro. (C) 2011 Elsevier Ltd. All rights reserved.

Outcomes and indicators, measurement tools, and databases for the National Action Plan for Promotion, Prevention and Early Intervention for Mental Health 2000

This publication is a support and resource document for the "National Action Plan for Promotion, Prevention and Early Intervention for Mental Health 2000". It includes indicators, measurement tools and databases relevant to assessing the implementation of the outcomes and strategies identified in the action plan.

Effect of Iron on Matrix Metalloproteinase Inhibition and on the Prevention of Dentine Erosion

It is known that some metal salts can inhibit matrix metalloproteinase (MMP) activity, but the effect of iron has not been tested yet. On the other hand, it has recently been suggested that MMP inhibition might influence dentine erosion. Based on this, the aims of this study were: (1) to test in vitro the effect of FeSO(4) on MMP-2 and -9 activity, and (2) to evaluate in situ the effect of FeSO(4) gel on dentine erosion. MMP-2 and -9 activities were analysed zymographically in buffers containing FeSO(4) in concentrations ranging between 0.05 and 1.5 mmol/l or not. Volunteers (n = 10) wore devices containing bovine dentine blocks (n = 60) previously treated with the following gel treatments: FeSO(4) (1 mmol/l FeSO(4)), F (NaF 1.23%; positive control) and placebo (negative control). The gels were applied once and removed after 1 min. Erosion was performed extraorally with Coca-Cola 4 times per day for 5 min over 5 days. Dentine wear was evaluated by profilometry. The data were analysed by Kruskal-Wallis and Dunn`s tests (p < 0.05). FeSO(4) inhibited both MMP-2 (IC(50) = 0.75 mmol/l) and MMP-9 (IC(50) = 0.50 mmol/l) activities. In the in situ experiment, the mean wear (+/- SD) found for the F gel (0.79 8 +/- 0.08 mu m) was significantly reduced in more than 50% when compared to the placebo gel (1.77 +/- 0.33 mu m), but the FeSO(4) gel completely inhibited the wear (0.05 +/- 0.02 mu m). Since FeSO(4) was able to inhibit MMP in vitro, it is possible that the prevention of dentine wear by the FeSO(4) gel in situ might be due to MMP inhibition, which should be investigated in further studies. Copyright (C) 2010 S. Karger AG, Basel

Emerging technologies for the prevention of dental caries. Are current methods of prevention sufficient for the high risk patient?

Fluorides and chlorhexidine are technologies that are 65 and 40 years old, respectively. This overview argues that current methods of caries prevention are not effective for the high caries risk patient. In this review examples, arguments and recommendations are provided to address the high caries risk patient that include: failure of comprehensive chemical modalities treatments to address the high caries risk patient; ecological alteration - would this be an effective approach?; and biomaterials and oral microbiome research to address the high caries risk patient.

The future of cognitive and behavioral therapies in the prevention and early management of psychosis: Opportunities and risks

Behavioral and cognitive interventions for people with psychosis have a long and distinguished history, although the evidence for their application to young people remains limited. We anticipate that the next decades will show substantial research into psychological intervention for this population. Important targets will include the management of environmental stressors, reduction of substance misuse, and promotion of early treatment. Psychological management of positive symptoms, depression, and suicidal behavior will continue to be critical objectives. Important secondary prevention goals will be the retention of cognitive functioning, vocational options, social skills, and social network support, including appropriate family support. We expect primary prevention to include both universal programs and interventions for adolescents at particularly high risk. Technical innovations will include increasing use of Internet-based intervention and behavior cueing devices. Pressures for intervention brevity will continue, as will problems with the systematic delivery of effective procedures.

Prevention of intraabdominal adhesions in Kasai portoenterostomy

An infant with biliary atresia had the right side of his liver covered with a sodium hyaluronate-based bioresorbable membrane during his initial Kasai portoenterostomy procedure. When his peritoneal cavity was entered 10.6 months (317 days) later for a liver transplant operation there was a remarkable absence of intraabdominal adhesions leading to a smooth operation and an uncomplicated recovery. J Pediatr Surg 36:1613-1614. Copyright (C) 2001 by W.B. Saunders Company.