SÁNCHEZ-SANHUEZA, G.; ALCÁNTARA-DUFEU, R.; CARRILLO, L.; MANSILLA, H.; NOVOA, C.& BELLO-TOLEDO, H. Ex vivo effect of copper sulfate on Enterococcus faecalis in root canal. Int. J. Odontostomat., 9(3):505-510, 2015.ABSTRACT: The incomplete disinfection of root canal system has been reported as the main cause of post-treatment disease, due to the persistence of bacteria. For over thirty years Enterococcus faecalis has been considered the most common bacterial species isolated from persistent root canal infections, resisting antibacterial agents, such as chlorhexidine and calcium hydroxide. Several studies have indicated that copper has optimal disinfecting capacities in a hospital environment. Aimed to know the ex vivo effect of copper sulfate (CuSO 4 ) on E. faecalis. Thirty-six extracted human tooth root canals were inoculated with E. faecalis ATCC 29212. These root canals had undergone endondontic procedures with a rotatory system. The effect of CuSO 4 was determined by plate count method of E. faecalis obtained from one sample of each tooth under three incubation times (4 th , 7 th and 10 th day). The canals medicated with CuSO 4 , the bacterial count decreased 6 log after 4 days and remained as such without statistically significant change until the tenth day. It is an indisputable fact of its antibacterial action. The bacterial persistence may be due to the ability of E. faecalis to remain viable in root canals up to 12 months without additional nutrients. These preliminary results could be used for further scientific work assessing the potential for the use of cooper in dentistry. SÁNCHEZ-SANHUEZA, G.; ALCÁNTARA-DUFEU, R.; CARRILLO, L.; MANSILLA, H.; NOVOA, C.& BELLO-TOLEDO, H. Ex vivo effect of copper sulfate on Enterococcus faecalis in root canal. Int. J. Odontostomat., 9(3):505-510, 2015.

Introduction An ideal filling material should hermetically seal the communication pathways between the canal system and surrounding tissues. Therefore, during the last few years, the development of obturation materials and techniques to create optimal conditions for the proper healing of apical tissues has been a focus of interest. The effects of calcium silicate‐based cements (CSCs) on periodontal ligament cells have been investigated, and promising results have been obtained. To date, there are no reports in the literature that have evaluated the biocompatibility of CSCs using a real‐time live cell system. Therefore, this study aimed to evaluate the real‐time biocompatibility of CSCs with human periodontal ligament cells (hPDLCs). Methodology hPDLC were cultured with testing media of endodontic cements for 5 days: TotalFill‐BC Sealer, BioRoot RCS, Tubli‐Seal, AH Plus, MTA ProRoot, Biodentine, and TotalFill‐BC RRM Fast Set Putty. Cell proliferation, viability, and morphology were quantified using real‐time live cell microscopy with the IncuCyte S3 system. Data were analyzed using the one‐way repeated measures (RM) analysis of variance multiple comparison test ( p < .05). Results Compared to the control group, cell proliferation in the presence of all cements was significantly affected at 24 h ( p < .05). ProRoot MTA and Biodentine lead to an increase in cell proliferation; there were no significant differences with the control group at 120 h. In contrast, Tubli‐Seal and TotalFill‐BC Sealer inhibited cell growth in real‐time and significantly increased cell death compared to all groups. hPDLC co‐cultured with sealer and repair cements showed a spindle‐shaped morphology except with cements Tubli‐Seal and TotalFill‐BC Sealer where smaller and rounder cells were obtained. Conclusions The biocompatibility of the endodontic repair cements performed better than the sealer cements, highlighting the cell proliferation of the ProRoot MTA and Biodentine in real‐time. However, the calcium silicate‐based TotalFill‐BC Sealer presented a high percentage of cell death throughout the experiment similar to that obtained.