36 research outputs found
A comparison of microhardness of indirect composite restorative materials Estudo comparativo da microdureza de materiais resinosos indiretos
The purpose of this study was to compare the microhardness of four indirect composite resins. Forty cylindrical samples were prepared according to the manufacturer’s recommendations using a Teflon mold. Ten specimens were produced from each tested material, constituting four groups (n=10) as follows: G1 - Artglass; G2 - Sinfony; G3 - Solidex; G4 - Targis. Microhardness was determined by the Vickers indentation technique with a load of 300g for 10 seconds. Four indentations were made on each sample, determining the mean microhardness values for each specimen. Descriptive statistics data for the experimental conditions were: G1 - Artglass (mean ±standard deviation: 55.26 ± 1.15HVN; median: 52.6); G2 - Sinfony (31.22 ± 0.65HVN; 31.30); G3 - Solidex (52.25 ± 1.55HVN; 52.60); G4 - Targis (72.14 ± 2.82HVN; 73.30). An exploratory data analysis was performed to determine the most appropriate statistical test through: (I) Levene's for homogeneity of variances; (II) ANOVA on ranks (Kruskal-Wallis); (III) Dunn's multiple comparison test (0.05). Targis presented the highest microhardness values while Sinfony presented the lowest. Artglass and Solidex were found as intermediate materials. These results indicate that distinct mechanical properties may be observed at specific materials. The composition of each material as well as variations on polymerization methods are possibly responsibles for the difference found in microhardness. Therefore, indirect composite resin materials that guarantee both good esthetics and adequate mechanical properties may be considered as substitutes of natural teeth.<br>O objetivo deste estudo foi comparar a microdureza de 4 resinas compostas indiretas. Quarenta amostras cilĂndricas foram obtidas com o auxĂlio de uma matriz de teflon, seguindo-se as recomendações dos fabricantes. Foram obtidas 10 amostras para cada material testado, contituindo-se 4 grupos (n=10) como se segue: G1-Artglass; G2-Sinfony; G3-Solidex; G4-Targis. A microdureza foi determinada pela tĂ©cnica da indentação Vickers com uma carga de 300g por 10 segundos. Quatro indentações foram realizadas em cada amostra, obtendo-se um valor mĂ©dio. Os dados da análise estatĂstica descritiva para cada condição experimental foram: G1-Artglass (mĂ©dia ± desvio padrĂŁo:55,26 ± 1,15HVN; mediana: 52,6); G2- Sinfony (31,22 ± 0,65HVN; 31,30); G3- Solidex (52,25 ± 1,55HVN; 52,60); G4- Targis (72,14 ± 2,82HVN; 73,30). Uma análise exploratĂłria dos dados foi realizada para determinar o teste estatĂstico mais apropriado: (I) Teste de Levene para variâncias homogĂŞneas; (II) Teste de ANOVA (Kruskal-Wallis); (III) Teste de comparação mĂşltipla de Dunn. O Targis apresentou os maiores valores de microdureza, enquanto que o Sinfony apresentou os menores valores. O Artglass e o Solidex se comportaram como materiais intermediários. Estes resultados indicaram que propriedades mecânicas distintas podem ser observadas nos materiais. A composição de cada material, bem como as variações nos mĂ©todos de polimerização sĂŁo possivelmente responsáveis pelas diferenças observadas na microdureza. Portanto, materiais resinosos indiretos que garantam estĂ©tica e propriedades mecânicas satisfatĂłrias podem ser considerados como substitutos dos dentes naturais
Gender reassignment surgery - a 13 year review of surgical outcomes
PURPOSE: The aim of this study is to thoroughly report on surgical outcomes from 332 patients who underwent male to female gender reassignment surgery (GRS). MATERIAL AND METHODS: Records from 332 patients who underwent GRS from 1995 to 2008 were reviewed. All patients were submitted to penile inversion vaginoplasty with glans-derived sensate clitoroplasty. Mean age was 36.7 years (range 19-68 years). Surgical complications were stratified in 6 main groups: genital region, urinary tract, gastrointestinal events, wound healing disorders and unspecific events. RESULTS: Progressive obstructive voiding disorder due to meatal stenosis was the main complication observed in 40% of the patients, feasibly corrected during the second setting. Stricture recurrence was found in 15%. Stricture of vaginal introitus was observed in 15% of the cases followed by 12% and 8% of vaginal stenosis and lost of vaginal depth, respectively. Rectal injury was seen in 3% and minor wound healing disorders in 33% of the subjects. CONCLUSION: Regarding male to female GRS, a review of the current literature demonstrated scarce description of complications and their treatment options. These findings motivated a review of our surgical outcomes. Results showed a great number of adverse events, although functionality preserved. Comparision of our outcomes with recent publications additionally showed that treatment options provide satisfying results. Moreover, outcomes reaffirm penile inversion vaginoplasty in combination with glans-derived sensate clitoroplasty as a safe technique. Nevertheless, discussing and improving surgical techniques in order to reduce complications and their influence on patient's quality of life is still strongly necessary and theme of our future reports