ABSTRACT
Fractured ceramic crowns can sometimes be repaired with composite resin. The aim of the current study was to determine the shear bond strength of composite to Feld spathic porcelain after CO[2] and Er:YAG laser porcelain surface preparation. In this in-vitro study, 36 Feldspathic porcelain blocksmeasuring 1*10*10 mm were divided into 3 groups of 12. Porcelain surfaces in the first and second groups were treated with 1.8W CO[2] laser and 5W Er:YAG laser irradiation, respectively. Third group specimens were subjected to 9.5% hydrofluoric acid surface conditioning. All groups received application of silane and adhesive after wards. A composite cylinder with 3.5 mm diameter and 5 mm height was bonded to specimens. In order to evaluate the shear bond strength, a Universal Testing Machine with crosshead speed of 1 mm/min was used. Statistical analysis was performed using one-way ANOVA and Tukey's HSD test and P<0.05 was considered statistically significant. The mean shear bond strength values [MPa] were 13.03 +/- 2.57%, 12.02 +/- 3.4 and 19.23 +/- 4.62, for the first, second and third groups respectively. One-way ANOVA revealed a statistically significant difference in this respect between the three groups [P< 0.001]. Tukey's HSD test demonstrated significant differences between the first and third groups [P= 0.000] as well as the second and third groups [P=0.000]. However, no significant difference was detected between the first and second groups [P =0.778]. Considering the study results, CO[2] or Er:YAG laser irradiation is not suggested as an appropriate alternative to hydrofluoric acid for surface preparation of Feld spathic porcelain
ABSTRACT
Chronic sinusitis is one of the most common medical problems and affected annually 30 million people in USA. This study the efficacy and safety of clarithromycin XL and Co-amoxiclove on clinical and CT scan finding in patients suffering from chronic sinusitis were compared. In this clinical trial a total of 59 subjects [62.7% male, 37.3% female, mean age 28 years] with clinical symptoms and CT scan findings of chronic sinusitis were divided into two groups and treated with clarithromycin XL or Co-amoxiclav. Clinical success rates at the end of therapy similar in two groups, but in subjects treated with clarithromycin XL, CT scan findings had a better results than Co-amoxiclav group [53% versus 29%]. Gastrointestinal discomfort was the most frequent treatment-related adverse effects, but no significant difference in two groups. Results demonstrated that clinical success rate of clarithromycin XL and Co-amoxiclav, was similar for treatment of chronic sinusitis, but clarithromycin XL was more effective in improvement of CT scan findings
Subject(s)
Humans , Male , Female , Clarithromycin , Amoxicillin-Potassium Clavulanate Combination , Chronic Disease , Tomography, X-Ray ComputedABSTRACT
One of the most important problems in dentistry is to produce a suitable bond between tooth and all ceramic restoration, but there is little information on the use of resin cements and the importance of different surface treatments on their adhesion to high alumina containing ceramics. The aim of this study was to find the optimal choice of surface treatments and luting cement for bonding to In-Ceram, an aluminum oxide reinforced glass ceramic material. The bond strength of two different luting cement to the ceramic material was evaluated. The effect of surface treatment, etching, sandblasting, and silanizing was also investigated. Thirty In-ceram discs were fabricated and assigned to 3 groups. Group 1 specimens were treated with HF and Silane, Group 2 were sandblasted and then silane was applied, Group 3 were treated only with silane. Rely X cement was placed on all specimens and shear bond strength test was done. After the test, the discs were polished again and treated as previously mentioned in 3 groups. Then they received Panavia F cement and shear bond strength was evaluated using Instron testing machine. Using Tukey HSD test, it was shown the Panavia F provided higher bond strength values than Rely X cement. One way ANOVA determined that the use of sandblast provided higher bond strength values than other groups. Surface etching with 9.5% HF also increased bond strength in comparison with silanization alone. Based on the results of this study, the use of Panaiva F was better for In-Ceram restorations. Sandbalsting is preferred to etching for the increase of bond strength of resin cements to alumina ceramic