Microbiological Study of Cast Posts before Cementation.

This study identifies the most common microorganisms present in type III gold cast posts related to pulpal disease and evaluates the sterilization/disinfection method before cementation in the root canal. Forty-five type III gold cast posts were aseptically collected in sterile sealed plastic bags and taken to the microbiology laboratory to carry out the study: fifteen cast posts had no treatment, fifteen were disinfected (immersion in 70% alcohol during 15 minutes), and fifteen were autoclaved at 121°C for 15 minutes by using saturated steam under 15 psi pressure. By using a two-proportion z-test, the difference was statistically significant (p > 0.05) and demonstrates that, in spite of the aseptic pattern used in the cast post collection and laboratory procedures, some cast posts arrive contaminated at the consulting office. The disinfection process worked out in a high percentage and demonstrated that the sterilization by autoclaving eliminated completely the pathogenic microbiota without affecting the cast post shape and integrity that could compromise their final fitting.

Streptococcus mutans y caries dental / Streptococcus mutans and dental caries

Streptococcus mutans es uno de los microorganismos cariogénicos asociados a la caries dental. De acuerdo con la hipótesis de la placa ecológica, la caries dental es la consecuencia de cambios en el balance natural de la microflora de la placa dental causados por la alteración de las condiciones ambientales locales (homeostasis microbiana oral). El estudio de su participación en la colonización de tejidos dentales, implantación e interacción con otros microrganismos es de mucha importancia para la comprensión de la dinámica de las biopelículas dentales. Por medio de técnicas de biología molecular, se ha avanzado en la identificación de los diferentes tipos que habitan la cavidad oral, los productos que generan y que son críticos para su implantación, las interacciones con otras especies y el desarrollo de nuevos procedimientos que ayuden su identificación como uno de los agentes más importantes en la caries dental. Esta revisión examina los últimos avances en la biología de Streptococcus mutans, su papel en la génesis de la caries y las técnicas de identificación y estudio más usadas en los últimos años.

Streptococcus mutans is one of cariogenic microorganisms associated with tooth decay. According with the hypothesis of the ecological plaque, dental caries is the consequence of changes in the natural balance in the dental plaque microflora (oral microbial homeostasis). Its role in the colonization of dental tissues, implantation and interaction with other microorganisms is of paramount importance for the understanding of the dynamics of dental biofilms. By means of molecular biology techniques, there have been advances in the identification of the different types that live in the oral cavity, the products they produce which are critical for its implantation, the interaction with other species and the development of new procedures that help its identification as one of the most important agents in dental caries. This review examines the latest advances in the biology of Streptococcus mutans, its role in the genesis of the caries and the identification and study techniques most used in recent years.