RESUMO
The prime objective of this study was to develop and test a method of modelling the dental root canal system using a vinyl resin, type UCAR-VYHD. It also aimed to verify if the resin models allow a three-dimensional evaluation of those features of the pulpal morphology of human permanent mandibular incisor teeth, which might be associated with periodontal disease. One hundred and eleven freshly extracted teeth were studied. Pre-extraction clinical records and periapical radiographs were used to deduce the presence or absence of periodontal disease. Each extracted tooth was radiographed in two perpendicular planes before being opened by conventional orthograde endodontic technique, and photographed in a scanning electron microscope. The patent pulp space was then obturated with the vinyl resin. Scanning electron photomicrographs of the resin replicas and of the teeth were compared with the earlier radiographic images to correlate the morphological findings. The numbers of root canals and apical foramina were recorded. This study showed that in mandibular incisors with periodontal disease there was a relatively low incidence of lateral canals (7.2%). The modelling technique was found to be reliable, reproducible, and provided sufficient detail to allow three-dimensional analysis of root canal morphology.
Assuntos
Calcificações da Polpa Dentária/patologia , Cavidade Pulpar/patologia , Incisivo/patologia , Modelos Dentários , Doenças Periodontais/complicações , Raiz Dentária/patologia , Adulto , Calcificações da Polpa Dentária/etiologia , Cavidade Pulpar/anatomia & histologia , Feminino , Humanos , Incisivo/anatomia & histologia , Masculino , Mandíbula , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Modelos Anatômicos , Reprodutibilidade dos Testes , Resinas Sintéticas , Raiz Dentária/anatomia & histologiaRESUMO
The purpose of this study was to evaluate and discuss the bactericidal effect of ultrasound when applied in the root canal of teeth with necrotic pulp and periapical lesions. Twenty newly extracted teeth were instrumented with an ultrasonic unit and K-files using 0.5% sodium hypochlorite as irrigating solution. Compacted debris and micro-organisms were frequently observed in the apical region and in dentinal tubules of the root canal wall. Overinstrumentation that sometimes occurred led to contamination of the periapical lesions with micro-organisms and debris from the root canal.
Assuntos
Cavidade Pulpar/microbiologia , Tratamento do Canal Radicular/instrumentação , Terapia por Ultrassom/instrumentação , Cavidade Pulpar/patologia , Desvitalização da Polpa Dentária/métodos , HumanosRESUMO
Hand instrumentation of the root canal was compared with ultrasonic instrumentation in 20 maxillary premolars with 2 root canals. The buccal and lingual canals were alternately instrumented by the 2 techniques until they had reached clinically ideal conditions for filling. After mechanical preparation, an attempt was made to evaluate root shape and the enlarging ability of the 2 techniques. For this purpose, a crosswise cut slice approximately 100 microns thick was cut off at the middle level of the root, which permitted comparative quantification of the instrumented area of the buccal and lingual canals. Crosscut serial sections of the remaining parts of the root were obtained for a systematic study of the entire extension of the root canal. It was concluded that the presence of debris inside the root canal depended more on the anatomical variation of the canal than on the technique used. No statistically significant differences in root canal area were evident at the middle third level of the root.
