A carregar...
Publicação
Influência da pressão pulpar positiva na difusão de peróxido de hidrogénio de um produto de branqueamento através dos tecidos dentários in vitro: ensaio piloto
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 1.09 MB | Adobe PDF |
Resumo(s)
Objetivos: Verificar se a pressão pulpar positiva (PPP) altera a difusão de peróxido de hidrogénio (PH) para a câmara pulpar através dos tecidos dentários, após aplicação de um produto de branqueamento. Desenho do estudo: Ensaio piloto in vitro. Materiais e Métodos: 20 dentes pré-molares e caninos foram divididos em quatro grupos (n=5). Todos foram seccionados horizontalmente 2-3mm abaixo da junção amelo-cementária; o tecido pulpar foi removido e as coroas foram montadas em placas de policarbonato de forma a simular PPP em dentes inferiores e superiores (grupos A e B) e pressão pulpar 0 (grupos C e D), respetivamente. Registou-se, para cada amostra, a espessura vestibular, volume da câmara pulpar, áreas de aplicação e exposição. A câmara pulpar foi preenchida com solução tampão acetato 2M. Foram recolhidas amostras antes e após o protocolo de branqueamento com 40% de PH, 6x20 minutos, e subsequentemente analisadas através do método de Leucocristal Violeta. Previamente foi realizada a titulação do gel de branqueamento para determinar a concentração de PH presente no lote utilizado. Os dados foram analisados estatisticamente através dos testes U de Mann-Whitney, teste de Wilcoxon e correlação de Spearman, e a significância considerada foi de p < 0,05. Resultados: Nos grupos A e B houve menores quantidade e percentagem de PH recuperado do interior da câmara pulpar, embora não estatisticamente diferentes entre eles (p > 0,05). Verificaram-se diferenças significativas entre quantidade de PH aplicado, recuperado, e controlo para todos os grupos (p < 0,05). Não foi possível estabelecer correlações entre espessura, volume da câmara pulpar e áreas de aplicação e exposição face à quantidade de PH recuperado. Conclusão: A pressão pulpar positiva leva a uma diminuição, embora não estatisticamente significativa, da quantidade de PH que atingiu a câmara pulpar através dos tecidos dentários após aplicação de PH a 40%.
Objectives: Determine if positive pulpal pressure (PPP) changes the hydrogen peroxide (HP) diffusion through tooth’s hard tissues into the pulpal chamber, after applying a bleaching agent. Study design: In vitro pilot study. Materials and Methods: 20 sound canines and premolars were divided into four groups (n=5). All of the samples were horizontally sectioned 2-3mm below the enamel-cementum junction; pulp tissue was removed and the crowns were fixed to polycarbonate simulating PPP in lower and upper teeth (groups A and B) and no pulpal pressure (groups C and D). For each sample was measured the vestibular thickness, pulp chamber volume and areas of application and exposure. The pulp chambers were filled with acetate buffer solution 2M. This solution was collected, from each sample, before and after the application of a bleaching gel containing 40% HP, and subjected to spectrophotometric analysis through the leuco-crystal violet method. Previously, the bleaching gel was titrated to determine the HP concentration in the used lot. Data was analyzed statistically through Mann-Whitney U test, Wilcoxon test and Spearman’s correlation, with a p-value under 0.05. Results: Groups A and B had less amounts and percentage of HP recovered from the pulp chamber, although not statistically different (p > 0.05). There were statistical differences between the amounts of HP applied on tooth surface, recovered, and control intervention (p < 0.05). No correlations were statistically relevant when analyzing tooth thickness, pulp chamber volume and areas of application and exposure versus the amount of HP recovered. Conclusion: PPP reduces the amount of HP recovered from the pulp chamber after applying a tooth bleaching gel of 40% HP.
Objectives: Determine if positive pulpal pressure (PPP) changes the hydrogen peroxide (HP) diffusion through tooth’s hard tissues into the pulpal chamber, after applying a bleaching agent. Study design: In vitro pilot study. Materials and Methods: 20 sound canines and premolars were divided into four groups (n=5). All of the samples were horizontally sectioned 2-3mm below the enamel-cementum junction; pulp tissue was removed and the crowns were fixed to polycarbonate simulating PPP in lower and upper teeth (groups A and B) and no pulpal pressure (groups C and D). For each sample was measured the vestibular thickness, pulp chamber volume and areas of application and exposure. The pulp chambers were filled with acetate buffer solution 2M. This solution was collected, from each sample, before and after the application of a bleaching gel containing 40% HP, and subjected to spectrophotometric analysis through the leuco-crystal violet method. Previously, the bleaching gel was titrated to determine the HP concentration in the used lot. Data was analyzed statistically through Mann-Whitney U test, Wilcoxon test and Spearman’s correlation, with a p-value under 0.05. Results: Groups A and B had less amounts and percentage of HP recovered from the pulp chamber, although not statistically different (p > 0.05). There were statistical differences between the amounts of HP applied on tooth surface, recovered, and control intervention (p < 0.05). No correlations were statistically relevant when analyzing tooth thickness, pulp chamber volume and areas of application and exposure versus the amount of HP recovered. Conclusion: PPP reduces the amount of HP recovered from the pulp chamber after applying a tooth bleaching gel of 40% HP.
Descrição
Tese de mestrado, Medicina Dentária, Universidade de Lisboa, Faculdade de Medicina Dentária, 2015
Palavras-chave
Branqueamento dentário Peróxido de hidrogénio Teses de mestrado - 2015