Comparative study of linear measurements performed in magnetic resonance and computed tomography images with the aid of an image realignment software / Estudo comparativo de medidas realizadas em imagens por ressonância magnética e por tomografia computadorizada com auxílio de um software de realinhamento de imagens

The aim of this study was to compare linear measurements of implant sites performed in magnetic resonance and computed tomography images with the aid of an image alignment software. Four patients from the Dental Implant Research and Teaching Center of Universidade Federal de Santa Catarina, Florianópolis, Brazil, were submitted to both computed tomography and magnetic resonance scans. An image realignment software was used to allow measuring the exact same sites on the images of both modalities. A total of eighty linear measuremensts of the posterior regions and twelve linear measurement of the anterior regions were performed with each modality. Measurements were carried out by one calibrated observer. Observer's reproducibility was higher than 97% (Dalberg's error). Student's t-test was used to compare the results of the height of the alveolar process in the computed tomography and magnetic resonance images. There was no statistically significant differences between the measurements performed in the computed tomography and magnetic resonance images (p = 0.4136). with a strong correlation between them (r = 0.8346). Similarly, there was no statistically significant differences between the measurements produced by the two modalities when the analysis discriminated the anterior and posterior regions (p = 0.7801 and p = 0.4381, respectively), with a strong correlation between the measurements in the posterior region of the jaws (r = 0.8547), and a weak correlation in the anterior region (r = 0.5472). Linear measurements of the alveolar process obtained from magnetic resonance and computed tomography images are comparable.

Avaliação laboratorial de sistemas adesivos de última geração / Laboratory evaluation of new adhesive systems

O presente trabalho teve por intenção avaliar laboratorialmente quatro novos sistemas adesivos dentinários: Optibond Solo, (Kerr); Prime & Bond 2.1, (Dentsply); Solid Bond, (Kulzer) e Syntac Sprint, (Vivadent). Foram realizados testes de resistência de união sob tensões de cisalhamento em dentina humana (n = 10). Comparando-se os resultados obtidos nos 4 diferentes grupos, verificou-se que os sistemas Optibond Solo e Solid Bond apresentaram resistência de união significantemente maior que os sistemas Prime & Bond 2.1 e Syntac Sprint. A interface dentina-sistema adesivo foi avaliada microscopicamente através da microscopia eletrônica de varredura