Accuracy of various imaging methods for detecting misfit at the tooth-restoration interface in posterior teeth.

PURPOSE: The present study aimed to evaluate which of the following imaging methods best assessed misfit at the tooth-restoration interface: (1) bitewing radiographs, both conventional and digital, performed using a photostimulable phosphor plate (PSP) and a charge-coupled device (CCD) system; (2) panoramic radiographs, both conventional and digital; and (3) cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Forty healthy human molars with class I cavities were selected and divided into 4 groups according to the restoration that was applied: composite resin, composite resin with liner material to simulate misfit, dental amalgam, and dental amalgam with liner material to simulate misfit. Radiography and tomography were performed using the various imaging methods, and the resulting images were analyzed by 2 calibrated radiologists. The true presence or absence of misfit corresponding to an area of radiolucency in regions subjacent to the esthetic and metal restorations was validated with microscopy. The data were analyzed using a receiver operating characteristic (ROC) curve, and the scores were compared using the Cohen kappa coefficient. RESULTS: For bitewing images, the digital systems (CCD and PSP) showed a higher area under the ROC curve (AUROC) for the evaluation of resin restorations, while the conventional images exhibited a larger AUROC for the evaluation of amalgam restorations. Conventional and digital panoramic radiographs did not yield good results for the evaluation of resin and amalgam restorations (P<.05). CBCT images exhibited good results for resin restorations (P>.05), but showed no discriminatory ability for amalgam restorations (P<.05). CONCLUSION: Bitewing radiographs (conventional or digital) should be the method of choice when assessing dental restoration misfit.

Complicações em coronectomia: estudo retrospectivo de 19 casos / Complications in coronectomy: retrospective study of 19 cases

Introdução: A Coronectomia ou Odontectomia parcial intencional é uma técnica cirúrgica, na qual se remove a coroa do dente, deixando a raiz in situ. É indicada quando há o risco de lesão ao nervo alveolar inferior ou fratura de mandíbula durante a remoção de dentes posteriores inferiores inclusos, particularmente os terceiros molares. Objetivo: Analisar as complicações trans e pós-operatórias e o índice de migração das raízes em 19 casos de coronectomia. Metodologia: Realizou-se um estudo retrospectivo através das informações contidas em prontuários e análise dos exames de imagem pré e pós-operatórios, com um período de acompanhamento que variou entre 6 meses e 4 anos e um mês de pós-operatório. Resultados: Foi observada uma queixa álgica e um caso de fragmento de esmalte dental residual. A migração radicular ocorreu em 89,5% dos casos e a movimentação média das raízes retidas foi de 3,21 milímetros, em um intervalo médio de 11 meses. Não foi necessária a reoperação de nenhum paciente. Conclusão: No presente estudo, a coronectomia mostrou-se ser uma boa opção à remoção completa do dente, com baixo índice de complicações... (AU)

Introduction: Coronectomy or Intentional Partial Odontoctomy is a surgical technique in which the crown is removed from the tooth that leaves the root in situ. It's indicated when there is a risk of injury to the inferior alveolar nerve or mandible fracture during the removal of included lower posterior teeth, particularly third molars. Objective: To analyze the trans and postoperative complications and the root migration index in 19 cases of coronectomy. Methodology: A retrospective study by the information contained in the medical records and analysis of the pre and post-operative imaging examinations was carried out, with a follow-up period ranging from 6 months to 4 years, and one month postoperatively. Results: Was observed a distress complaint and a case of residual dental enamel fragment were observed. The root migration occurred in 89.5% of the cases and the mean root movement was 3.21 millimeters, in an average interval of 11 months. No patient reoperation was required. Conclusion: In the present study coronectomy proved to be a good option for complete tooth removal, with a low rate of complications... (AU)

Avaliação dos níveis de pressão sonora emitidos pelo aparelho de ressonância magnética / Study about the consequences of different sound pressure levels emitted by magnetic resonance imaging equipment

RESUMO Objetivo: mensurar o nível de pressão sonora emitido pelo aparelho de ressonância magnética em funcionamento e verificar as sensações auditivas descritas pelos indivíduos submetidos a este exame após a realização do mesmo. Métodos: foi realizada a mensuração do ruído produzido, durante a aquisição das imagens, por meio de um medidor de nível de pressão sonora (decibelímetro) e a aplicação de um questionário com a finalidade de verificar as sensações auditivas apresentadas por estes indivíduos após a realização do exame. Tal procedimento foi aplicado a 60 indivíduos submetidos ao exame de ressonância magnética do crânio. Resultados: o nível de pressão sonora média apresentada durante a realização do exame foi inferior ao nível de intensidade considerado como risco para lesões auditivas. No entanto, sensações como zumbido, ansiedade, plenitude auricular e alívio após o término do exame foram citados pelos indivíduos após a execução do mesmo. Conclusão: é pertinente o uso de protetores auriculares como medida preventiva para o controle do nível de ruído que atinge a cóclea do indivíduo, minimizando desta forma os efeitos físicos e psicossociais decorrentes da exposição ao ruído.

ABSTRACT Purpose: to measure the sound pressure level emitted by the magnetic resonance imaging in operation and check the auditory sensations described by individuals submitted to this examination after it has been carried out. Methods: the measurement of the deep noise was conducted during image formation in this examination, by means of sound pressure level meter (decibel meter) and the application of a questionnaire for the purpose of checking the hearing sensations presented by those individuals after the exam has been carried out. This procedure was applied to sixty individuals submitted to a magnetic resonance imaging of the skull. Results: it was found that the average of sound pressure level presented while the examination was carried out was lower than the level of intensity considered being a risk for auditory damages. However sensations like tinnitus, anxiety, auricular plenitude and relief after the end of the examination were mentioned by the individuals after it had been carried out. Conclusion: the use of hearing protectors is relevant as a preventive measure for controlling the level of noise that affects the individual's cochlea, thus minimizing the physical and psycho-social effects resulting from noise exposure.