Antimicrobial effect of endodontic solutions used as final irrigants on a dentine biofilm model.

AIM: To evaluate the residual biovolume of live bacterial cells, the mean biofilm thickness and the substratum coverage found in mixed biofilms treated with different endodontic irrigant solutions. METHODOLOGY: Twenty-five bovine dentine specimens were infected intraorally using a removable orthodontic device. Five samples were used for each irrigant solution: 2% chlorhexidine, 1% sodium hypochlorite (NaOCl), 10% citric acid, 17% EDTA and distilled water. The solutions were used for 5 min. The samples were stained using the Live/Dead technique and evaluated using a confocal microscope. Differences in the amount of total biovolume (µm(3)), number of surviving cells (µm(3)), mean biofilm thickness (µm) and substratum coverage (%) of the treated biofilms were determined using nonparametric statistical tests (P < 0.05). RESULTS: Similar values of biovolume total, biovolume of live subpopulations and substratum coverage were found in 2% chlorhexidine, 10% citric acid, 17% EDTA and distilled water-treated biofilms (P > 0.05). The lower values of the studied parameters were found in 1% NaOCl-treated dentine (P < 0.05) with the exception of the mean biofilm height criteria that did not reveal significant differences amongst the irrigant solutions (P > 0.05). CONCLUSIONS: One per cent sodium hypochlorite was the only irrigant that had a significant effect on biofilm viability and architecture.

Técnica para realizar perforaciones radiculares cervicales en dientes de perros empleada para trabajos de investigación / Technique to accomplish root cervical perforations in dog´s teeth employed for investigation projects

El propósito del presente trabajo es proporcionar a investigadores, especialistas y alumnos de postgrado una técnica estandarizada que facilite la realización de perforaciones radiculares en dientes de perros, limitando errores y estableciendo una técnica base para llevar a cabo estos defectos dentarios. En este tipo de estudios el objetivo principal es evaluar la respuesta de los tejidos periodontales radiculares que ocasionan los materiales odontológicos para el sellado de las perforaciones. Para su realización es importante considerar factores como el tamaño y nivel de la perforación, la irrigación abundante, el tiempo de exposición y si el sellado se realizó inmediatamente o pasado algún tiempo, si están contaminadas o no. Asimismo se pretende limitar variables como la edad de los animales, enfermedad periodontal y el nivel de desarrollo radicular con la finalidad de establecer un patrón y que los factores ya mencionados no condicionen los resultados o resulten en falsos positivos

The purpose of the present work is provide to investigating, specialists and alumnis a standardized methodology that facilitate the root perforations accomplishment in dogs´ teeth, limiting mistakes and establishing a technical base to carry out these dental defects. In this type of studies the principal objective is to evaluate response of the root tissue periodontal that cause the dental materials for the sealed of the perforations. For your accomplishment is important to consider factors as the size and level of the perforation, the abundant irrigation, the exposition time and if the sealed was accomplished immediately or past some time, if they are contaminated or not. Also it es intended to limit variable as the age of the animals, periodontal disease and the root development level in order to establish a standard and that the already mentioned factors do not condition the results or result in untruthful positive

Evaluación de la limpieza del sistema de conductos radiculares con gel de clorhexidina y gel de EDTA utilizando microscopía electrónica de barrido / SEM evaluation of root canal cleaning with clorhexidine and EDTA gel

Se evaluó por medio de microscopia electrónica de barrido la capacidad de limpieza del sistema de conductos radiculares, utilizando gel de clorhexidina, gel de EDTA y suero fisiológico. Se utilizaron 30 caninos superiores extraídos, a los cuales se les realizó abertura coronaria, utilizando durante la preparación gel de clorhexidina a 2%, gel de EDTA a 24% y suero fisiológico. Se evaluaron las paredes de los conductos con el microscopio electrónico de barrido y los resultados mostraron que los conductos tratados con gel de EDTA a 24%, se encontraron más limpios, con diferencia estadística en relación con los tratados con gel de clorhexidina a 2% y suero fisiológico

It was evaluated by means microscope scanning electron a capacity of cleaning of the root system, using chlorhexidine gel, EDT A gel and physiologic serum. 30 extracted superior canines were used, to which were carried out coronary opening, during their preparation were used chlorhexidine 2% gel, EDT A 24% gel and physiologic serum. Evaluation with scanning electron microscope showed that the root system tried with EDT A 24% gel were cleaner with statistically difference to tried with chlorhexidine 2% gel and physiologic serum

Tratamiento de perforaciones radiculares en dientes de perros con dos marcas comerciales de agregado trióxido mineral (MTA) / Root perforations treatment in dog´s teeth with two agregate mineral trioxide (MTA)

El propósito de este trabajo fue evaluar la respuesta de los tejidos periodontales interradiculares de dientes de perros, perforados y sellados inmediatamente con ProRoot MTA y MTA-Angelus. Concluido el tratamiento de conductos radiculares, se realizaron en cada diente perforaciones en la raíz mesial, a nivel de la entrada del conducto radicular, en dirección de la furca. 90 días después los perros fueron sacrificados por perfusión y las muestras procesadas para estudio microscópico. Los resultados mostraron neoformación de tejido mineralizado, sellando totalmente la perforación en todos los casos y mínima inflamación de tipo crónico, consecuente del extravasamiento de material sellador. La prueba no paramétrica de Kruskal-Wallis demostró no existir diferencia estadísticamente significante entre ambos materiales. El ProRoot MTA y el MTA-Angelusson materiales con adecuadas propiedades biológicas y crean las condiciones ideales para que ocurra la reparación de los tejidos periodontales interradiculares en dientes de perros

The purpose of this work was to evaluate tbe response of the periodontal tissue of dogs' teeth which was perforated and sealed immediately witb ProRootMTA and MTA-Angelus. Concluded the treatment of root canals, they were carried out in each tooth perforations in the root mesial, at level of the entrance of the root canal, in direction of the furca. 90 days later the dogs were sacrificed by perfusionand processed for microscopic study. The results showed neoformation of tissue mineralized sealing the perforation totally in all the cases and mínimum inflammation of chronic type, consequent of the extravasation of sealer material. The non parametric test of Kruskal Wallis demonstrated not to exist differs statistically significant between both materials. The ProRoot MTA and tbe MTA-Angelus are material with appropriate biological properties and believe the ideal conditions so that it happens the repair of the periodontal tissue in dogs'teeth

Conventional and digital radiographic methods in the detection of simulated external root resorptions: a comparative study.

OBJECTIVES: The purpose of this study was to evaluate and to compare the efficacy of a conventional and a digital radiographic method in diagnosing simulated external root resorption cavities. METHODS: Human dry mandibles containing teeth were covered with bovine muscle slices in order to simulate the soft tissues. Nine teeth from each dental group were investigated. Three periapical radiographs of each tooth were taken in an orthoradial, mesioradial and distoradial aspect using conventional film (Insight Kodak F-speed; Eastman Kodak, Rochester, NY) and a digital sensor (DRS Gnatus System; Gnatus, Ribeirao Preto, Brasil). The teeth were extracted using a forceps and had 0.7 mm and 1.0 mm deep cavities prepared on their vestibular, mesial and distal surfaces at the cervical, middle and apical thirds. Following preparation, each tooth was replaced in its alveolus and new radiographs were taken. Three dental professionals, an endodontist, a radiologist and a general practioner, evaluated the images. RESULTS: A larger number of cavities (P<0.05) were detected by the digital method when compared with the conventional method, for all depths of lesions. CONCLUSIONS: The results of this study suggest that the digital radiographic method is more sensitive than conventional radiography to detect simulated external root resorption cavities.