| Objective: To study Enterococcus faecalis effect in the expression of tumor necrosis factor receptor associated factor-6(TRAF-6) in the process of rat periapical periodontitis.Methods: 39 adult male Sprague-Dawley rats were randomly divided into two groups: pulp cavity exposed group (A group) and enclosed group with Enterococcus faecalis in pulp cavity (B group),each group had three rats and was detected at 2 week, 4 week and 6 week; The group A was conducted the rat right mandibular first molar pulp mest open surgery which the canal directly exposed to the oral environment,The group B is in the nest opening surgery,pulp cavity was enclosed with Enterococcus faecalis. In control group,the model was left no any depression.At 2week ,4 week and 6 week ,X ray and cone beam CT were taken.Take the first molar and mandibular periapical tissue scraped, the mandibular first molar in the center of the nesial and distal in the direction of the frozen sections were performed TRAF-6 immunohistochemical staining, HE staining, anti- tartaric acid phosphatase (TRAP) staining and RT-PCR, The statistical analysis was conducted by SPSS.Results:1. X ray and cone beam CT showed significant apical shadow after 4 week, A group and B group was significantly great shadow area ,rat periapical periodontitis model was made successfully .2.HE staining result showed that A group and B group have a large number of inflammatory cell infiltration and formate abscess the right mandibular first molar and apical area at 2 weeks. Two groups have a large number of lymphocytes at 4 weeks and 6 weeks. Health group had nothing changed.3. Immunohistochemical staining result showed that pulp cavity exposed group (A group): open pulp 2 week, the expression of TRAF-6 was significantly increased; after 4 week, the expression of TRAF-6 decreased; after 6 week, the expression of TRAF-6 was in stable; normal control group has no TRAF-6 positive cells; 2 week, 4 week, 6 week group were significantly different (P <0.05), 4 week and 6 week group had no significant difference between groups (P> 0.05). Periapical surgery in maxillary in osteoclasts 2 week, 4 week, 6 week were more than the control group, and was significantly different; 2 week group and 4 week, 6 week group was also difference (P <0.05), 4 week and 6 week group had no group significant difference(P>0.05); Enterococcus faecalis in pulp cavity enclosed group (B group): had no first molar periapical region TRAF-6 positive cells; after 2 week, the expression of TRAF-6 was significantly increased; after 4 week,the expression of TRAF-6 was significantly decreased; after 6 week, the expression of TRAF-6 in stable; 2 week, 4 week, 6 week group were significantly different (P <0.05), 2 week group and 4 week, 6 week group had also difference(P <0.05), 4 week and 6 week group had no significant difference between groups (P> 0.05).4.TRAP staining result show that periapical surgery in maxillary in osteoclasts 2 week, 4 week, 6 week were more than the control group, and were significantly different; 2 week group and 4 week, 6 week group also differed (P <0.05), 4 week and 6 week group had no group significant difference (P>0.05); B group were significantly different with A group (P <0.05).5. RT-PCR result show that the pulp cavity exposed group (A group): in 0 day group and 2 week, 4 week, 6 week, the expression of TRAF-6 mRNA group were significantly different (P <0.05),in 2 week group and 4 week, 6 week group ,the expression of TRAF-6 mRNA was also significantly different (P <0.05),in 4 week group 6 week group ,the expression of TRAF-6 mRNA was not significantly different (P> 0.05);root canal enclosed in Enterococcus faecalis group (B group):in 0 day group and 2 week,4 week, 6 week group ,the expression of TRAF-6 mRNA were significantly different (P <0.05), in 2W group and 4W, 6W group, the expression of TRAF-6 mRNA was also significantly different (P <0.05),in 4 week group 6 week group ,the expression of TRAF-6 mRNA was no significantly different(P>0.05).Conclusion:1.TRAF-6 is an important signaling molecule in the process of periapical periodontitis bone resorption.The expression of TRAF-6 was closely related to the periapical ,and TRAF-6 expression was the strongest in the acute phase . 2.Enterococcus faecalis infected apical process, TRAF-6 was closely related expression; and in the main bacteria Enterococcus faecalis of periapical periodontitis process, the expression of TRAF-6 was significantly higher than that caused by the canal directly exposed during apical expression of TRAF-6.3.In a bacterium Enterococcus faecalis as the main cause of apical process, the differentiation of osteoclasts markedly enhanced the process of periapical periodontitis bone resorption which was significantly accelerated. |
PDF Full Text Request