In vivo evaluation of tissue response to new endodontic sealers

Resumo

The sealers can be in direct contact with the periapical
tissues. Thus, these materials must have appropriate physical and
biological properties, providing conditions for repair to occur.
Objective: The aim of this study was to evaluate the response of rat
subcutaneous tissue to endodontics sealers. Material and methods:
Three materials comprised the groups: group I – Zinc Oxide, Eugenol
and Iodoform paste, group II – Portland cement with propylene
glycol, and group III – MTA Fillapex® (Angelus). These materials were
placed in polyethylene tubes and implanted into dorsal connective
tissue of Wistar rats for seven and 15 days. The specimens were
stained with hematoxylin and eosin and evaluated regarding to
inflammatory reaction parameters through a light microscope. The
data were compared using Kruskal-Wallis test with significance level
of 5%. The intensity of inflammatory response against the sealers was analyzed by two blinded and previously calibrated observers
for all experimental periods. Results: The histological evaluation
showed that all the materials caused a moderated inflammatory
reaction at seven days which decreased with time. A greater
inflammatory reaction was observed at seven days in group I. The
other specimens had significantly less inflammatory cells when
compared to this group. Tubes with MTA Fillapex® presented some
giant cells, macrophages and lymphocytes after seven days. At 15
days, the presence of fibroblasts and collagen fibers was observed
indicating normal tissue healing. The group II showed similar
results to those observed in MTA Fillapex® already at seven days.
At 15 days the inflammatory reaction presented was almost absent
at the tissue, with many collagen fibers indicating normal tissue
healing. Statistical analysis showed a significant statistical difference
amongst the group I (seven days) and II (15 days) (p < 0.05). In the
other groups no significant statistical differences were observed.
Conclusion: MTA Fillapex® and Portland cement with propylene
glycol were more biocompatible than the other tested cements.