RESUMEN
PURPOSE: The aim of this study was to evaluate the effect of low-thickness ceramic laminate translucency on water sorption and solubility in resin luting agents. METHODS AND MATERIALS: Ceramic slides (15×0.7 mm) were generated using lithium disilicate (IPS e.max Press, Ivoclar-Vivadent, Schaan, Liechtenstein) that were A1 in color and had decreasing degrees of translucency (high, medium, and low). A slide of transparent glass of similar size was used as the control. Under each slide, 15 specimens (8×0.5 mm) of differing composite materials from the same manufacturer (3M ESPE Dental Products, St Paul, MN, USA) were prepared (n=5): light-cured resin cement (RelyX Veneer); dual-cured resin cement (RelyX ARC); and flowable composite (Z350XT Flow). To evaluate the loss or gain of mass, the specimens were dried until a constant mass was reached. Then, they were immersed in water for seven days and weighed immediately following removal from water. Subsequently, the specimens were dried again until a constant mass was obtained. The mass measurements were used to calculate the water sorption and solubility. Statistical analyses were carried out using a two-way analysis of variance and the Tukey test. RESULTS: Under the high-translucency ceramic slides, all of the luting agents showed similar performance regarding water sorption; the flowable composite resin and the light-cured resin cement had the lowest solubility values. Under the medium- and low-translucency surfaces, the dual-cured resin cement and the flowable composite resin showed better performance with respect to water sorption and solubility. CONCLUSIONS: In the case of high-translucency laminates, luting agents with different activation methods might be used. However, even in thin sections, decreasing the translucency of the laminate led to significant loss of light penetration, indicating a decreased likelihood of the physical activation of the resin cement.
RESUMEN
The influence of vitamin D on the severity of systemic lupus erythematosus (SLE) has been studied. Our objectives were to determine the prevalence of vitamin D insufficiency in Brazilian lupus patients and its relationship with demographic, clinical, and laboratory variables and to study the relationship between vitamin D insufficiency and disease activity. This is a cross-sectional study of 159 SLE patients. Levels of serum 25-hydroxyvitamin D (25(OH)D) <30 ng/ml were defined as vitamin D insufficiency and <20 ng/ml as deficiency. Data collected included sex, age, ethnicity, postmenopausal status, disease duration, cumulative amount of oral glucocorticoids (GC) in the last six months, duration of GC usage, calcium and vitamin D supplements, photosensitivity, sunscreen usage, sun exposure, diabetes mellitus, creatinine clearance, lifestyle habits, and smoking. Disease activity was measured by the SLE Disease Activity Index 2000 (SLEDAI-2K). Bivariate statistical analysis was performed using the Mann-Whitney test, Spearman's correlation coefficient, Chi-square test, and Fisher's exact test. Multivariate analysis was performed with multiple linear regression. The prevalence of vitamin D insufficiency and deficiency were 37.7% and 8.2%, respectively. Levels of 25(OH) D were not associated with lupus activity score, disease duration, sun exposure, vitamin D supplementation, or use of corticosteroids.