Intérêt du laser CO2 pour l’adhésion des résines composites sur la dentine

CO2 laser irradiation brings about structural modifications at the dentin surface. The aim of this study was to compare the tensile strength of composite resin bonded to unlased dentin and lased dentin. Dentin specimens were prepared by vestibular surface sectionning, exposing a plane dentinal surface. 40 specimens received 20 individual laser impacts with a power of 4 W and a duration of 0.1 s. 20 specimens received no laser irradiation. Half of the 60 specimens was treated with Scotchbond 2™ and the other one with Schotchbond Multipurpose™. Composite cylinders were polymerised for 40 seconds to these specimens. Tensile bond strengths were determined at a crosshead speed of 5 mm/min and fractured surfaces were examined at SEM after the test. Unlased dentin had significantly higher bond strength that the lased dentin.Le but de notre étude a été de vérifier si les modifications subies par la dentine, consécutivement au rayonnement d’un laser CO2, amélioraient le collage de certains systèmes adhésifs dentinaires. Après avoir choisi un tir de 4 watts et de 0,1 seconde, nous avons réalisé 20 impacts laser sur des surfaces dentinaires.La moitié des échantillons a été ensuite traitée avec le système adhésif Scotchbond 2™, l’autre moitié avec le système Scotchbond Multipurpose™. Puis des cylindres de composite ont été photopolymérisés sur ces surfaces. Un test de traction a été appliqué sur les échantillons ainsi préparés et sur un groupe témoin n’ayant pas subi de tirs laser. Les surfaces fracturées après le test ont été observées au M.E.B. côté dentine et côté composite. Nous n’avons pas obtenu une amélioration de l’adhésion après le traitement laser avec les deux systèmes adhésifs testés

Severity of cardiovascular disease outcomes among patients with HIV is related to markers of inflammation and coagulation

BACKGROUND: In the general population, raised levels of inflammatory markers are stronger predictors of fatal than nonfatal cardiovascular disease (CVD) events. People with HIV have elevated levels of interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP), and D-dimer; HIV-induced activation of inflammatory and coagulation pathways may be responsible for their greater risk of CVD. Whether the enhanced inflammation and coagulation associated with HIV is associated with more fatal CVD events has not been investigated. METHODS AND RESULTS: Biomarkers were measured at baseline for 9764 patients with HIV and no history of CVD. Of these patients, we focus on the 288 that experienced either a fatal (n=74) or nonfatal (n=214) CVD event over a median of 5 years. Odds ratios (ORs) (fatal versus nonfatal CVD) (95% confidence intervals [CIs]) associated with a doubling of IL-6, D-dimer, hsCRP, and a 1-unit increase in an IL-6 and D-dimer score, measured a median of 2.6 years before the event, were 1.39 (1.07 to 1.79), 1.40 (1.10 to 1.78), 1.09 (0.93 to 1.28), and 1.51 (1.15 to 1.97), respectively. Of the 214 patients with nonfatal CVD, 23 died during follow-up. Hazard ratios (95% CI) for all-cause mortality were 1.72 (1.28 to 2.31), 1.73 (1.27 to 2.36), 1.44 (1.15 to 1.80), and 1.88 (1.39 to 2.55), respectively, for IL-6, D-dimer, hsCRP, and the IL-6 and D-dimer score. CONCLUSIONS: Higher IL-6 and D-dimer levels reflecting enhanced inflammation and coagulation associated with HIV are associated with a greater risk of fatal CVD and a greater risk of death after a nonfatal CVD event. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrial.gov Unique identifier: SMART: NCT00027352, ESPRIT: NCT00004978, SILCAAT: NCT00013611

Mesure du hiatus dent-matériau de restauration: Intérêt du MEB

The purpose of this article was to describe a method of measuring the interface between cavity walls and restorative materials and to evaluate it by comparing the interface of amalgam, composite restorations and cavity walls. With the different restorative materials the interface could be measured. Its value was dependent of the type of restoration. This methodology is available for ail restorative biomaterials. It could be of interest in clinical evaluation of restorative materials.Cet article décrit une méthode de mesure du hiatus dent-matériau de reconstitution dentaire. Cette méthode a été évaluée en comparant les valeurs moyennes du hiatus au niveau de restaurations au composite et à l’amalgame. Quel que soit le matériau employé, un hiatus a pu être mis en évidence et mesuré. La valeur de cet hiatus dépend de la nature du matériau de restauration et varie en fonction du temps. Cette méthode, applicable à tous les matériaux d’obturation, pourrait représenter un critère supplémentaire dans l’évaluation d’un matériau d’obturation

Analyse au microscope électronique à balayage et au rugosimètre d’impacts laser CO2 sur la dentine

The aim of the study was to compare the morphology of craters produced on the dentinal surface by CO2 laser beams (LASERSATtmCO2) before and after the removal of the carbonized layer, besides with different seetings of the power and duration of the laser beam.Thirty-three recently extracted non carious young third molar teeth were sectionned from vestibular and lingual surfaces, exposing a planed dentinal surface. Twenty impacts were made on each of dentinal surface producing 20 individual craters. The duration and the power of each laser beam were different on each tooth. The duration varied from 0.1 to 0.4 second (0.1 - 0.2 - 0.3 - 0.4 s). The power varied from 1 to 5 watts (1, 2, 3, 4, 5 w).Specimens obtained for a power of 3 and 4 watts and a duration of 0.1 and 0.2 second were examined with a JEOL 35CF (25 KV, magnification: x 30, x 110, x 200), before and after the removal of the carbonized layer. The carbonized layer of the craters was removed with an air polisher (HEATCO).Craters obtained for ail duration values as well as for ail power values were analyzed with a profilometer. The chosen profilometer was: TALISURF 10; horizontal amplification Vh = 20; vertical amplification Vv = 200.Samples were observed by a SEM and the craters depth and diameter were measured with a profilometer. Then, the carbonized layer of the craters was removed with an airpolisher and the cleaned dentinal surface was observed again with the SEM and the profilometer. Measurements were entered in a computer (using the SIPHAR programm) in order to calculate the mean values of the depth, the diameter and the area, for ail test conditions.It appears that the carbonized layer is not adherent to the dentine and can be easily removed. From the mean values, we can conclude that the diameter is about four times larger than the depth for the nocleaned craters and is about five to six times larger than the depth for the cleaned craters. The profils of the craters cannot be used for retention pins in the composite adhesion but the adhesion area is increased after a laser beam.Cette étude a pour but d’observer et de quantifier les cratères produits par un tir focalisé discontinu au laser CO2 (Lasersattm), avant et après élimination de la couche carbonisée par un aéropolisseur. Trentetrois molaires, extraites et indemnes de caries, sont coupées en deux dans le sens mésio-distal et leurs faces vestibulaires et linguales sont sectionnées pour donner une surface dentinaire plane. Vingt cratères sont réalisés par un tir focalisé discontinu sur chaque surface dentinaire. Les temps d’application et les puissances du rayonnement utilisés sont respectivement: 0.1, 0.2, 0.3, 0.4 seconde et 1, 2, 3, 4, 5 watts. Ces cratères sont analysés au microscope électronique à balayage et au rugosimètre, avant et après élimination de la couche carbonisée. Les résultats obtenus sont traités à l’aide du logiciel SIPHAR sur PC; nous obtenons un profil moyen du cratère pour chaque puissance et temps d’application utilisés. Les résultats sont les suivants: le diamètre est environ quatre fois plus grand que la profondeur avant élimination de la couche carbonisée et est cinq à six fois plus important après élimination de cette couche. Le diamètre et la profondeur des cratères sont plus importants après élimination de la couche carbonisée. La couche carbonisée a une épaisseur régulière sauf au fond du cratère où elle est plus faible que sur les parois. Avant élimination de la couche carbonisée le profil du cratère est un cône, après élimination de la couche, le profil est un cône tronqué. En conclusion, les cratères obtenus ne peuvent être considérés comme des ancrages efficaces pour d’éventuels collages dentinaires avec des composites; toutefois la surface d’adhésion s’en trouve considérablement accrue

PO-0638: Adaptive dose painting by numbers for head and neck cancer: interim analysis of a randomised trial

International audience1. Recherches sur le Fayuan zayuan yuanshi ji de Sengyou (445-518), première anthologie de rites bouddhiques (suite : le contenu des juan 4 et 5) Notre travail de reconstruction du Fayuan zayuan yuanshi ji 法苑雜緣原始集 (Anthologie [pour comprendre] le commencement et l’origine de diverses [pratiques] dans le jardin des devoirs ; ci-après Fayuan) de Sengyou 僧祐 (445-518) nous a amenés cette année à nous pencher sur les 22 premiers titres de la section sur le saṃgha (Sengbao 僧寶, « Le joyau de la Loi ..

Pulmonary function is associated with distal aortic calcium, not proximal aortic distensibility. MESA lung study

Forced expiratory volume in one second strongly predicts mortality from cardiovascular disease. FEV1 has been associated with aortic stiffness a strong independent predictor of cardiovascular mortality. However, the anatomical site and possible mechanisms linking aortic stiffness and lung function are unknown. We therefore examined if FEV1 and CT percent emphysema were associated with calcification of the abdominal aorta or reduced distensibility of the proximal thoracic aorta.The Multi-Ethnic Study of Atherosclerosis (MESA) measured aortic calcification on cardiac and abdominal CT scans and proximal aortic distensibility using magnetic resonance among participants aged 45–84 years without clinical cardiovascular disease. Spirometry was measured following ATS/ERS guidelines and percent emphysema was measured in the lung fields of cardiac CT scans. Multivariate analyses adjusted for age, sex, race/ethnicity and cardiovascular risk factors. Of 1,917 participants with aortic distensibility measures, 13% were current and 38% were former smokers. Eighteen percent had airflow limitation without asthma. FEV1 was associated with the extent of distal aortic calcification (0.76; 95%CI 0.60–0.97, p = 0.02) but not proximal aortic calcification or proximal aortic distensibility (−0.04 mmHg−1; 95%CI −0.16–0.09 mmHg−1, p = 0.60). Percent emphysema was associated with neither measure. FEV1 was associated with severity of distal aortic calcification where it was present independently of smoking and other cardiovascular risk factors but not with distensibility or calcification of the proximal aorta

Effects of High Flavanol Dark Chocolate on Cardiovascular Function and Platelet Aggregation.

Regular consumption of chocolate and cocoa products has been linked to reduced cardiovascular mortality. This study compared the effects of high flavanol dark chocolate (HFDC; 1064mg flavanols/day for 6 weeks) and low flavanol dark chocolate (LFDC; 88mg flavanols/day for 6 weeks) on blood pressure, heart rate, vascular function and platelet aggregation in men with pre-hypertension or mild hypertension. Vascular function was assessed by pulse wave analysis using radial artery applanation tonometry in combination with inhaled salbutamol (0.4 mg) to assess changes due to endothelium-dependent vasodilatation. HFDC did not significantly reduce blood pressure compared to baseline or LFDC. Heart rate was increased by LFDC compared to baseline, but not by HFDC. Vascular responses to salbutamol tended to be greater after HFDC. Platelet aggregation induced by collagen or the thromboxane analogue U46619 was unchanged after LFDC or HFDC, whereas both chocolates reduced responses to ADP and the thrombin receptor activator peptide, SFLLRNamide (TRAP6), relative to baseline. Pre-incubation of platelets with theobromine also attenuated platelet aggregation induced by ADP or TRAP6. We conclude that consumption of HFDC confers modest improvements in cardiovascular function. Platelet aggregation is modulated by a flavanol-independent mechanism that is likely due to theobromine.This study was supported by a grant (to R. Corder) from Barry Callebaut Belgium N