Effect of the carbon dioxide 10,600-nm laser and topical fluoride gel application on enamel microstructure and microhardness after acid challenge: an in vitro study.

The aim of this in-vitro study was to evaluate positive effects of the carbon dioxide laser (CO2, 10,600 nm) with acidulated phosphate fluoride (APF) gel on enamel acid resistance. Twenty extracted human third molars (40 surfaces) were randomly assigned into four groups: group C, untreated control; group L, CO2 laser alone group; group F, APF 1.23% fluoride gel; and group FL, APF 1.23% gel and laser. Samples from group L were irradiated with a CO2 laser for 30s. The parameter settings used were average power, 0.73 W; time on, 100 µs; time off, 40 ms; tip-to-tissue distance, 20 mm; tip diameter 700 µm; and energy density with movements, 5 J/cm2. Samples from group F were treated with the APF gel for 4 min, and the gel was washed off with distilled water. The enamel samples from group FL were treated with APF gel for 4 min and then irradiated with the CO2 laser for 30s without removing the gel. Each enamel sample was placed in 50 ml soft drink (pH = 2.75) for 10 min then rinsed with deionized water and stored in artificial saliva at 37 °C for 1 h. Samples were assessed for Vickers hardness number (VHN) before and after treatments and subjected to SEM analysis. Data were analyzed using a one-way analysis of variance (ANOVA) and Tukey's test (α < 0.05). After the acid challenge, the untreated C group was demineralized to a great extent and the enamel surface was with the lowest mean score of microhardness. The observed VHN in the control (C group) had a mean value of 176.13, the scores in the CO2 laser group (L group) were with mean value of 238.40, the F group with a mean value of 218.45, and the fluoride-treated and laser-irradiated FL group-with a mean of 268.28 VHN. Paired t test performed to compare groups C, L, F, and FL has shown that group FL has greater resistance to decrease in microhardness of dental enamel (P ≤ 0.05) on exposure to acidic protocol. After the acid challenge, the fluoride-treated and laser-irradiated samples (group FL) showed the least diminution in enamel surface microhardness. The sub-ablative carbon dioxide laser irradiation in combination with fluoride treatment is more effective in protecting enamel surface and resisting demineralization than CO2 laser irradiation or fluoride alone.

Ageing and blood pressure modulate the relationship between metabolic syndrome and aortic stiffness in never-treated essential hypertensive patients. A comparative study.

OBJECTIVE: The aim of this study was to evaluate the impact of the metabolic syndrome (MS) and its components as defined by the National Cholesterol Education Program Adult Treatment Panel III on arterial stiffness in untreated hypertensive patients. METHODS: This was a cross sectional multi-center study performed in 46 healthcare centers, from 14 countries involved in the Complior study. Four hundred and forty patients (55% male) aged 18-73 years, with untreated essential hypertension were selected at inclusion. All patients underwent a full evaluation for all the risk factors representing the MS and an assessment of arterial stiffness using automatic measurement of carotid-femoral pulse wave velocity (PWV). RESULTS: In the overall population significant correlations were found, respectively, between PWV, MS (R=0.2, P<0.001) and gender (R=0.11, P=0.023) where PWV was higher in women. After adjustment for age and systolic blood pressure (SBP), analysis of covariance showed an independent effect of the MS on PWV, this effect increased with ageing and SBP especially after 47 years (age median, P=0.0047). Moreover, increase of mean PWV was highly associated with the number of MS factors in global population (P<0.001). These findings suggest that MS leads to early arterial wall ageing. CONCLUSIONS: Presence of MS induces an increase of arterial stiffness in untreated hypertensive patients independently from age and SBP. The increase of PWV is proportional to number of risk factors and affects principally patients after mid-age of 47 years where MS has ageing effects on arterial stiffness.

[Efficacy of candesartan cilexetil in hypertensive patients with or without diabetes]. / Efficacité du candesartan cilexetil chez les hypertendus diabétiques ou non diabétiques.

OBJECTIVE: To assess the effect of an ARB, candesartan cilexetil (CC), on blood pressure (BP) from 5 double-blind, randomised, studies in hypertensive patients. METHODS: Similar design was used in the 5 selected studies. Following 2-4 weeks run-in period with placebo, patients were randomised to receive the double-blind treatment. BP were assessed at inclusion, after 4-6 weeks and at the end (8-12 weeks). Depending on the BP response, dosage of CC 8 mg was doubled at the follow-up visit if BP >or=140/90 mmHg. RESULTS: 702 patients were randomised in CC group of whom 22% (153) were diabetic. Mean BP was 160 +/- 13/94 +/- 10/65 +/- 14 mmHg for SBP/DBP/PP at inclusion and were significantly reduced to 141 +/- 15/83 +/- 10/58 +/- 13 mmHg (p<0.001) after 8-12 weeks. The results according to the diabetes status are presented in the table below: [table: see text] CONCLUSION: Results of this meta analysis analysis performed on individual data show that CC reduces significantly BP in hypertensive population with a significant decrease in the diabetic patients.