No technique or material, when individually considered, was capable of achieving the mechanical strength of the sound teeth; however, the association of reattachment technique Circumferential chamfer with bonding system Single Bond could approximate the immediate impact strength of the restored teeth to that observed in the sound teeth.
Objectives-This study evaluated the kinetics of water uptake and percent conversion in neat versus ethanol-solvated resins that were formulated to be used as dental bonding agents.Methods-Five methacrylate-based resins of known and increasing hydrophilicities (R1, R2, R3, R4 and R5) were used as reference materials. Resins were evaluated as neat bonding agents (100% resin) or they were solvated with absolute ethanol (95% resin/5% ethanol or 85% resin/15% ethanol). Specimens were prepared by dispensing the uncured resin into a circular mold (5.8 mm × 0.8 mm). Photo-activation was performed for 80 s. The water sorption/diffusion/solubility were gravimetrically evaluated, while the degree of conversion (DC) was calculated by Fouriertransform infrared spectroscopy.Results-Water sorption increased with the hydrophilicity of the resin blends. In general, the solvated resins exhibited significantly higher water sorption, solubility and water diffusion coefficients when compared to their corresponding neat versions (p<0.05). The only exception was resin R1, the least hydrophilic resin, in which neat and solvated versions exhibited similar water sorptions (p>0.05). Addition of ethanol increased the DC of all tested resins, especially of the least hydrophilic, R1 and R2 (p<0.05). Despite the increased DC of ethanol-solvated methacrylate-based resins, it occurs at the expense of an increasing in their water sorption/ diffusion and solubility values. Significance-Negative effects of residual ethanol on water sorption/solubility appeared to be greater as the hydrophilicity of the resin blends increased. That is, the use of less hydrophilic resins in dental adhesives may create more reliable and durable bonds to dentin.
NIH Public Access
ObjectivesThe aim of the present study was to assess the effect of the exposure to
food-simulating liquids prior to brushing simulation on the surface roughness of
five composite materials (Quixfil, Filtek Supreme, Esthet-X, Filtek Z250, Tetric
Ceram). Material and methodsTwenty cylinders (5 mm diameter and 4 mm height) of each composite were randomly
allocated to 4 groups (n=5), according to the food-simulating liquid in which they
were immersed for 7 days at 37ºC: artificial saliva, heptane, citric acid, and
ethanol. After this period, the top surface of composite cylinders was submitted
to 7,500 brushing cycles (200 g load). Measurements of the surface roughness (Ra,
µm) were carried out before and after the exposure to the chemicals/brushing
simulation. Changes on the morphology of composite surfaces were observed through
scanning electron microscopy (SEM). ResultsThe statistical analysis (ANOVA with cofactor / Tukey's test, α=5%) detected a
significant interaction between solutions and composite resins. Esthet-X, Filtek
Z250 and Tetric Ceram were not affected by the food-simulating
liquids/toothbrushing. Citric acid and ethanol increased the surface roughness of
Quixfil and Filtek Supreme, respectively. SEM images corroborate the surface
roughness findings, demonstrating the negative effect from chemical solutions and
mechanical abrasion. ConclusionsThe surface roughness of composite resin materials are differently affected by the
food-simulating solutions, depending on the immersion media.
In this study, the effects of acupuncture in comparison with flat occlusal plane appliance were evaluated in patient with myogenic temporomandibular dysfunction (TMD). The sample consisted of 40 women with TMD and unbalanced energy predominance of Yang Liver Ascension, selected using the Renying and Cunkou pulses, randomly divided into two groups: acupuncture and splint. The effect of treatments on the masseter and anterior temporal muscles was evaluated after 4 weeks of treatment, by means of electromyographic activity (root mean square) and pain pressure threshold. Pain intensity was measured using the visual analog scale, and range of mouth opening was evaluated using a millimeter ruler. All evaluations were performed at the beginning and end of the treatment. Visual analog scale score was reduced equally in the two groups (p < 0001), and the increase in range of mouth opening was significant in both groups. A significant difference was detected only in pain pressure threshold of the left masseter in the acupuncture group (p < 0.05). Only root mean square in the at rest position of the right temporal muscle diminished in the final stage of the splint group (p < 0.05). Both treatments reduced the pain intensity of myogenic TMD in the short term and may be considered strategies for control of chronic pain related to TMD.
Signs and symptoms were correlated with microorganisms. Endodontic treatment was effective in reducing bacteria and endotoxins but was not capable of completely removing them from the root canal.
AH Plus/gutta-percha provided superior root canal sealing at both immediate and 180-day time periods. The presence of a coronal seal reduced leakage significantly. Storage of root filled specimens did not disturb the sealing ability of the tested materials.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.