Root Canal Shaping by Single-File Systems and Rotary Instruments: a Laboratory Study

Introduction: The aim of this study was to compare the shaping ability of two single-file systems and conventional rotary instruments in severely curved root canals of extracted human molars. Methods and Materials: Mesiobuccal canals of 120 mandibular molars with angles of curvature ranging between 25° and 35° and radii of curvature from 5 to 9 mm, were divided into three groups (n=40). In each group the canals were instrumented with either WaveOne (W), Reciproc(R) or ProTaper (P). The time required for canal shaping and the frequency of broken instruments were recorded. The standardized pre and post-instrumentation radiographs were taken to determine changes in working length (WL) and straightening of canal curvature. The presence of blockage or perforation was also evaluated. Data were analyzed using the one-way analysis of variance (ANOVA) and post-hoc Tukey’s test. The level of significance was set at 0.05. Results: Both single-instrument systems reduced the canal preparation time by approximately 50% (P<0.05). No incidence of broken instruments from single-file systems was reported; however, two F2 instruments in the P group were broken (P<0.05). Reduction in WL and straightening of canal curvature was observed in all three systems with the highest scores belonging to P system (P<0.05). No case of blockage or perforation was found during shaping in any group. Conclusion: Single-file systems shaped curved canals with substantial saving in time and a significant decrease in incidence of instrument separation, change in WL, and straightening of canal curvature

Gutta-percha et endodontie (étude en Calorimétrie Différentieile à Balayage (DSC))

PARIS7-Odontologie (751062104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Investigation sur la dynamique des solutions d'irrigation lors de la préparation canalaire en rotation continue avec le système Protaper®

PARIS7-Odontologie (751062104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Le minéral trioxyde aggrégate, ou MTA (données actuelles et investigation sur le temps de prise)

En 2001, une première revue de littérature a mis en exergue les potentialités d un nouveau matériau: le MTA. Son champ d utilisation en endodontie s étend de l obturation a rétro au traitement des perforations, en passant par le coiffage puipaire et l obturation définitive des dents permanentes immatures. Depuis cette période, de nombreuses études ont confirmé les capacités de scellement du MTA, significativement supérieures aux matériaux usuels, et ont mis en évidence qu il s agit d un ciment endodontique biocompatible et bioactif. En effet, le MTA stimule la réparation du tissu pulpaire, la cémentogenèse et l ostéogenèse. Ce matériau montre également une grande similitude avec le ciment de Portland. Sur le marché, le MTA est maintenant disponible blanc et non plus gris comme initialement. Lors de l utilisation clinique, des différences sensibles entre les deux produits ont été constatées, notamment en ce qui concerne le temps de prise. Un des objectifs de ce travail a été de comparer le temps de prise du M I A gris et du MTA blanc. Les résultats de notre étude ont montré une différence importante dans la réaction de prise entre les deux produits. Par ses propriétés, le MTA demeure aujourd hui le matériau de choix pour la réparation pulpaire et parodontale.PARIS7-Odontologie (751062104) / SudocSudocFranceF

La Parodontite apicale en 2003 (de la genèse à la guérison)

PARIS7-Odontologie (751062104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Etude expérimentale comparative de l'étanchéité apicale du nouveau matériau d'obturation canalaire RESILON face à la gutta-percha

PARIS7-Odontologie (751062104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Intérêt du laser Néodyme (YAP dans la pulvérisation des instruments fracturés: une étude pilote)

PARIS7-Odontologie (751062104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

LE MINERAL TRIOXIDE AGGREGATE, OU MTA, UN NOUVEAU MATERIAU POUR DE NOUVELLES INDICATIONS CLINIQUES EN ENDODONTIE

PARIS7-Odontologie (751062104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Centering Ability and Influence of Experience When Using WaveOne Single-File Technique in Simulated Canals

Introduction. WaveOne is a single endodontic instrument that reciprocates with a dedicated motor to shape root canal systems. The present study assessed the centering ability of this simplified protocol along with the effect of experience in simulated plastic canals. Methods. One experienced operator shaped two groups of simulated canals. Groups 1 and 3 each comprised 30 blinded L-shaped canals or S-shaped canals, respectively. Photographs were taken before and after shaping and digitally assessed centering after superimposition of the pictures. Time of shaping, number of passes, canal aberrations, and instrument degradation were recorded. In group 2 shaping was done on 30 blinded L-shaped canals by 30 different students with no prior experience with WaveOne. Results. All three groups yielded satisfactory, reproducible shaping. Centering ratios were low and homogeneous in all groups, with no significant differences between the experienced operator and the students. Apical transportation values were very low (≤0.138 mm) with no instances of blockage or separation. The average shaping time was short (43 to 101,6 sec). Conclusions. Within the limits of the study, the WaveOne instrument had excellent centering ability with a low risk of fracture or blockage and a short shaping time, regardless of the operator’s level of experience