Histological evaluation of MTA as a root-end filling material.

AIM: To assess the histological response associated with grey mineral trioxide aggregate (GMTA) and zinc oxide eugenol (ZOE) as root-end filling materials in teeth where the root canals were not filled and the coronal access cavities were not restored. METHODOLOGY: Periapical lesions were developed in 24 premolar teeth in three dogs. The root canals were prepared and half of them were dried, filled and the coronal access restored (closed). The remaining teeth were not root filled and no coronal restoration was placed (open). Apical root-end resections were performed 3 mm from the apex, and root-end cavities were prepared with ultrasonic tips. These were randomly filled with either ZOE or GMTA in the same number of specimens using MAPSYSTEM device. After 180 days the animals were killed and blocks of tissues removed and processed for histological examination. Periradicular tissue reaction was evaluated, including severity of inflammation and cementum formation. Statistical analysis was performed using anova analysis and Tukey's test. RESULTS: A significant difference was found between the levels of inflammation in the periradicular tissues of the GMTA/closed group, compared with the ZOE/open and ZOE/closed groups (P < 0.05) but not between GMTA/closed and GMTA/open groups. Cementum formation was not found over any ZOE specimens but over MTA in all specimens. No microorganisms were found in the interface between the material and the dentinal walls. CONCLUSIONS: GMTA was associated with less periapical inflammation and tissue response when used as a root-end filling material, even when no root filling or coronal restoration was present.

Filtración marginal tras la obturación de perforaciones radiculares laterales con distintos materiales / Marginal leakage after obturation of root perforations with different materials

En este estudio se emplearon 30 dientes humanos uniradiculares recientemente extraídos. Se partieron los dientes en dos mitades y cada mitad recibió 2 perforaciones. Las perforaciones fueron rellenadas con los siguientes materiales: 1- Sealapex con óxido de zinc y óxido de calcio, 2- Sealapex con óxido de zinc, 3- Sealapex, 4- ionómero de vidrio, 5- MTA Ângelus, 6- Amalgama, 7- Cemento Portland, 8- Pro Root MTA. Después de 48 horas en cámara húmeda, los especímenes fueron inmersos en azul de metileno al 2% al vacío y las filtraciones marginales evaluadas linealmente. Los mejores resultados fueron obtenidos con los materiales 1, 2 y 3 (p=0,05)

Thirty human single rooted tooth recently extracted were employed in this study. The tooth were seccioned longitudinally in the middle and each half received two perforations. The perforations were filled with the following materials: 1- Sealapex with zinc oxide and calcium oxide, 2- Sealapex with zinc oxide, 3- Sealapex, 4- Glass ionomer, 5- Angelus MTA., 6-Amalgam, 7-Porland cement, 8-Pro Root MTA. The teeth remained in a damp camera for 48 hours and then were placed into a 2% methylene blue dye solution under vacuum, and leakage was linearly evaluated. The results showed better results with the sealers 1,2 and 3 (p=0.05)