Background: Root canal infections is caused by the colonization of microorganisms. Microorganisms that commonly found in root canal failure is Enterococcus faecalis. These bacteria can be found in 80-90% of root canal infections. Currently, many plants are used as antibacterial drugs. Pineapple is one plant that can be used as antibacterial drugs. Pineapple peel has a variety of antibacterial chemical compounds, such as, bromelain, saponins, tannins and flavonoids that can inhibit the growth of Enterococcus faecalis bacteria. Aim: To obtain concentration of antibacterial from pineapple peel extract on Enterococcus faecalis growth. Methods: This study was an experimental laboratory with Post Test Only control group design using Enterococcus faecalis ATCC 29212 bacteria that were diluted based on Mc. Farland standard 1.5 x 108 CFU / ml with pineapple peel extract treatment concentration of 100%, 50%, 25%, 12.5%, 6.25%, 3.125%, 1.56%, 0, 78% and then planted in nutrient agar media surface evenly. Results: At concentration of 3.125% pineapple peel extract showed that the growth of colonies was less than 90% of positive control and concentration of 6.25% pineapple peel extract had no visible Enterococcus faecalis bacteria growth as much as 99.9%. Conclusion: The pineapple peel extract (Ananas comosus) have antibacterial power on the growth of Enterococcus faecalis bacterial colonies with Minimal Inhibitory Concentration (MIC) of 3.125% and the Minimum Bactericidal Concentration (MBC) of 6.25%.

Background. The main etiology of endodontic treatment failure is caused by bacteries that stay in the root canal. E.faecalis is a bactery that is found as an etiology of endodontic treatment failure. Cell wall of this bacteria is containing Lipoteichoic acid (LTA). LTA can penetrate into the periradicular tissue, act as endotoxin in host and cause periradicular inflammation then lead to bone destruction. Bone destruction occurs due to the inflammation process that is mediated by immune system. The important cell in the process of bone destruction is osteoclast. Bone destruction is marked by the form of osteoclast that is called osteoclastogenesis. NFATc-1 and osteocalcin play important things in osteoclastogenesis. Purpose. The aim of this study is to know about the expression of NFATc-1 and osteocalcin during the periapical bone destruction due to induction of E.faecalis. Method. This study used laboratory experimental with the post test only control group design. A total of 54 male rats were randomly divided into 2 main groups, which each main group had 3 subgroups. Group A (control) : every tooth was induced only by sterile BHIb. Group A had 3 subgroups (A Control day 3, 10, and 21), group B : every tooth was induced by 10 μl BHI-b E.faecalis ATCC212(106 CFU), it was contained 3 sub groups (B day 3,10, and 21). The animals were sacrificed based on their days scheduled group and prepared for histological examination of periapical bone, then we did the immunohistochemistry followed by calculation on the light microscope. Result. The analysis revealed that the expression of NFATc-1 and osteoclast increased significantly in group B when E.faecalis was induced. Conclusion. From this study we know that the expression of NFATc-1 and osteocalcin are increasing during the periapical bone destruction that induced by E.faecalis.