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OBJECTIVE: The present study was designed to investigate interfacial quality between both Epiphany and Epiphany SE and the surrounding dentin having conventional gutta-percha/AH plus root filling as reference for comparison. STUDY DESIGN: A sample of 36 human maxillary canines was prepared and assigned to experimental groups of 12 teeth each, designated as G1, Resilon/Epiphany; G2, Resilon/Epiphany SE; and G3, gutta-percha/AH Plus. After the filling procedures, each specimen was horizontally sectioned at 3, 6, and 8 mm from the apex and a metallographic preparation was performed to enable the evaluation under Confocal Laser Scanning Microscopy (CLSM). The integrity of the interface was determined by calculating the ratio between the total sealer/dentin interface and the sealer/dentin interface that presented gap-containing regions. Additionally, the width of each gap was measured and pooled per each specimen for comparison. Statistical analysis was performed using nonparametric methods. RESULTS: Nonbonding AH Plus/gutta-percha root fillings showed a significantly higher amount of gap-free regions (P < .05). In the same way, nonbonding AH plus root fillings displayed significantly narrower gaps compared with the 2 adhesive root-filling groups (P < .05). CONCLUSIONS: Under the present in vitro conditions, the quality of the interfacial adaptation of the current adhesive root fillings is compromised even when teeth with simple anatomic features were obturated under well-monitored laboratory conditions.

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OBJECTIVE: This study was designed to quantitatively evaluate the amount of dentin debris extruded from the apical foramen by comparing the conventional sequence of the ProTaper Universal nickel-titanium (NiTi) files with the single-file ProTaper F2 technique. STUDY DESIGN: Thirty mesial roots of lower molars were selected, and the use of different instrumentation techniques resulted in 3 groups (n=10 each). In G1, a crown-down hand-file technique was used, and in G2 conventional ProTaper Universal technique was used. In G3, ProTaper F2 file was used in a reciprocating motion. The apical finish preparation was equivalent to ISO size 25. An apparatus was used to evaluate the apically extruded debris. Statistical analysis was performed using 1-way analysis of variance and Tukey multiple comparisons. RESULTS: No significant difference was found in the amount of the debris extruded between the conventional sequence of the ProTaper Universal NiTi files and the single-file ProTaper F2 technique (P>.05). In contrast, the hand instrumentation group extruded significantly more debris than both NiTi groups (P<.05). CONCLUSIONS: The present results yielded favorable input for the F2 single-file technique in terms of apically extruded debris, inasmuch as it is the most simple and cost-effective instrumentation approach.

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O objetivo deste estudo foi avaliar a espessura mínima radicular remanescente e o desgaste porcentual do terço cervical em raízes mesiais de molares inferiores, após a instrumentação com as técnicas ProTaper Universal e Lima única F2. Foram obtidos 100 primeiros molares inferiores com raízes completamente separadas. Desse total, foram selecionados e incluídos no estudo somente 22 que possuíam dois canais distintos na raiz mesial, comprimento entre 20 e 22 mm e grau de curvatura da raiz mesial com angulação variando entre 10° e 20°. Destes, 8 foram eliminados por possuírem uma anatomia muito discrepante, o que limitava o processamento e análise digital das imagens (PADI). Os dentes foram acessados e a patência apical foi realizada em todos os canais determinando o comprimento de trabalho. Em cada dente, cada canal mesial foi instrumentado por uma técnica diferente. As amostras foram posicionadas em um dispositivo de montagem e digitalizadas através de microtomografia computadorizada antes e depois de serem completamente instrumentadas. O volume de interesse, correspondente à região de zona de risco, com uma grande margem de tolerância, tanto em direção apical quanto em direção cervical, foi determinado por 234 fatias, totalizando um comprimento vertical de 3,5 mm, para avaliação quantitativa comparativa. Através de PADI mediu-se, de forma automática, a espessura mínima radicular nos dois canais mesiais, antes e após a instrumentação, para todas as fatias de todos os dentes. A partir destes dados foi calculado o desgaste porcentual. Após o tratamento estatístico das mais de 6500 medidas obtidas, pôde-se concluir que não existiu diferença no desgaste da zona de risco produzido pelas duas técnicas de instrumentação testadas. Em todos os casos a espessura radicular remanescente permaneceu dentro de uma margem de segurança, não havendo, portanto, nenhum caso de rasgo ou perfuração. Dessa forma, ambas as técnicas estudadas foram consideradas seguras quanto ao ...

The aim of the present study was to evaluate the minimal remaining root canal thickness and percentage of dentin removed of the cervical third of the mesial roots mandibular molars after instrumentation with the ProTaper Universal and Single File F2 Techniques. From a total of 100 teeth, only 22 were selected and included in the study by having two distinct canals in the mesial root with length between 20 and 22 mm and degree of curvature presenting angle between 10° and 20°. Eight specimens were eliminated because they have a very disparate anatomy that limited the digital processing and analysis of the images (PADI). The teeth were accessed and patency was performed in all canals determining the working length. In each tooth, each mesial canal was instrumented by a different technique. The samples were placed in a mounting device and scanned by microcomputed tomography before and after instrumentation. The corresponding volume of interest to the region of the risk zone was determined by 234 slices, with a total vertical length of 3.5 mm, for quantitative comparative evaluation with a high degree of tolerance. The PADI performed the measures automatically of the minimal thickness of root in both mesial canals, before and after instrumentation for all slices of each tooth. From these data, the percentage of dentin removed was calculated. After statistical analysis of more than 6500 measurements, it was concluded that there was no difference in the wear of the risk zone produced by the two instrumentation techniques tested. In all instrumented specimens, the root thickness remained within a security margin, thus, no case of strip perforation was ...

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INTRODUCTION: The present study was designed to investigate the bond strength produced by Epiphany and Epiphany SE to root canal dentin. METHODS: A sample of 36 human upper canines was prepared and assigned to experimental groups (n = 12), designated as group 1, Resilon/Epiphany; group 2, Resilon/Epiphany SE; and group 3, AH Plus/gutta-percha. After the filling procedures, each tooth was prepared for push-out assessment by using root slices of 1-mm thickness. Loading was performed on a universal testing machine at a speed of 0.5 mm/min. One-way analysis of variance and Tukey test for multiple comparisons were used to compare the results among the experimental groups. RESULTS: AH Plus/gutta-percha root fillings showed significantly higher push-out bond strength than both Resilon/Epiphany and Resilon/Epiphany SE (P < .05). There was no significant difference between Epiphany/Resilon and Epiphany SE/Resilon (P > .05). CONCLUSIONS: Under the present in vitro conditions, the adhesiveness quality to root dentin promoted by both Epiphany sealers is compromised even when teeth with simple anatomic features were obturated under well-monitored laboratory conditions.

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