Rat subcutaneous tissue response to MTA Fillapex® and Portland cement.

The aim of this study was to evaluate the response of rat subcutaneous tissue to MTA Fillapex® (Angelus), an experimental root canal filling material based on Portland cement and propylene glycol (PCPG), and a zinc oxide, eugenol and iodoform (ZOEI) paste. These materials were placed in polyethylene tubes and implanted into the dorsal connective tissue of Wistar rats for 7 and 15 days. The specimens were stained with hematoxylin and eosin, and evaluated regarding inflammatory reaction parameters by optical microscopy. The intensity of inflammatory response against the sealers was analyzed by two blinded and previously calibrated examiners for all experimental periods (kappa=0.96). The histological evaluation showed that all materials caused a moderate inflammatory reaction at 7 days, which subsided with time. A greater inflammatory reaction was observed at 7 days in the tubes filled with ZOEI paste. Tubes filled with MTA Fillapex presented some giant cells, macrophages and lymphocytes after 7 days. At 15 days, the presence of fibroblasts and collagen fibers was observed indicating normal tissue healing. The tubes filled with PCPG showed similar results to those observed in MTA Fillapex. At 15 days, the inflammatory reaction was almost absent at the tissue, with several collagen fibers indicating normal tissue healing. Data were analyzed by the nonparametric Kruskal-Wallis test (α=0.05). Statistically significant difference (p<0.05) was found only between PCPG at 15 days and ZOEI at 7 days groups. No significant differences were observed among the other groups/periods (p>0.05). MTA Fillapex and Portland cement added with propylene glycol had greater tissue compatibility than the PCPG paste.

Rat subcutaneous tissue response to MTA Fillapex® and Portland cement

The aim of this study was to evaluate the response of rat subcutaneous tissue to MTA Fillapex® (Angelus), an experimental root canal filling material based on Portland cement and propylene glycol (PCPG), and a zinc oxide, eugenol and iodoform (ZOEI) paste. These materials were placed in polyethylene tubes and implanted into the dorsal connective tissue of Wistar rats for 7 and 15 days. The specimens were stained with hematoxylin and eosin, and evaluated regarding inflammatory reaction parameters by optical microscopy. The intensity of inflammatory response against the sealers was analyzed by two blinded and previously calibrated examiners for all experimental periods (kappa=0.96). The histological evaluation showed that all materials caused a moderate inflammatory reaction at 7 days, which subsided with time. A greater inflammatory reaction was observed at 7 days in the tubes filled with ZOEI paste. Tubes filled with MTA Fillapex presented some giant cells, macrophages and lymphocytes after 7 days. At 15 days, the presence of fibroblasts and collagen fibers was observed indicating normal tissue healing. The tubes filled with PCPG showed similar results to those observed in MTA Fillapex. At 15 days, the inflammatory reaction was almost absent at the tissue, with several collagen fibers indicating normal tissue healing. Data were analyzed by the nonparametric Kruskal-Wallis test (α=0.05). Statistically significant difference (p<0.05) was found only between PCPG at 15 days and ZOEI at 7 days groups. No significant differences were observed among the other groups/periods (p>0.05). MTA Fillapex and Portland cement added with propylene glycol had greater tissue compatibility than the PCPG paste.

O objetivo deste estudo foi avaliar a resposta do tecido subcutâneo de rato ao MTA Fillapex® (Angelus), a um cimento endodôntico experimental à base de cimento Portland e propilenoglicol, e à pasta de óxido de zinco e eugenol com iodofórmio. Estes materiais foram colocados em tubos de polietileno e implantados no tecido conjuntivo do dorso de ratos Wistar, por 7 e 15 dias. Os espécimes foram corados com hematoxilina e eosina e os parâmetros de reação inflamatória foram avaliados em microscópio óptico. A intensidade da resposta inflamatória provocada pelos cimentos foi analisada em todos os períodos por dois observadores previamente calibrados (kappa 0,96) e sem conhecimento dos grupos experimentais. O exame histológico mostrou que todos os materiais provocaram reação inflamatória moderada aos 7 dias que regrediu com o tempo. A maior resposta inflamatória do tecido foi observada aos 7 dias, nos tubos preenchidos com pasta de Óxido de Zinco e Eugenol com Iodofórmio. Os tubos com MTA Fillapex apresentaram algumas células gigantes, macrófagos e linfócitos após 7 dias. Aos 15 dias, a presença de fibroblastos e fibras de colágenas foi observada, indicando processo de cicatrização do tecido. Os tubos com o cimento Portland mostraram resultados semelhantes aos observados no grupo MTA Fillapex. Aos 15 dias, a reação inflamatória apresentada foi praticamente ausente, com muitas fibras colágenas, indicando cicatrização normal do tecido. A análise estatística mostrou diferença estatisticamente significante entre o grupo de cimento Portland (15 dias) e óxido de zinco eugenol com Iodofórmio (7 dias) (p<0,05). Nos outros grupos não houve diferença estatística significante. MTA Fillapex e cimento Portland são mais biocompatíveis do que os outros cimentos testados.

Evaluation of tissue response to MTA and Portland cement with iodoform.

OBJECTIVE: The aim of this study was to evaluate the biocompatibility of Portland cement with the addition of iodoform, compared to MTA (ProRoot). STUDY DESIGN: Eighteen Wistar albino rats were divided into 3 groups of 6 animals each. Polyethylene tubes were filled either with freshly mixed MTA or Portland cement mixed with iodoform (20% wt/wt) and implanted subcutaneously. An empty tube served as control. After 7, 30, or 60 days, the implants together with the surrounding tissues were removed in blocks. Sections were evaluated for the presence and thickness of a fibrous capsule, presence of granulation tissue, and the severity of inflammatory response. Data were submitted to nonparametric statistical analysis with individual comparisons between groups at a significance level of P < 0.05. RESULTS: There were no differences between inflammatory responses at 7 and 30 days. After 60 days from surgical removal, there was significantly more tissue reaction to the MTA and Portland cement compared to the control group. CONCLUSION: There were no significant differences regarding inflammatory responses between MTA and Portland cement with iodoform after 7, 30, or 60 days. After 60 days, the fibrous capsule around the Portland cement appeared more organized than tissue surrounding MTA implants. After 60 days, there was still a significantly increased tissue reaction to the 2 cements compared to the empty polyethylene tubes.