title: [Bactericidal effects and smear layer removal of Er:YAG-laser radiation against Enterococcus faecalis in root canals].
abstract: To evaluate the cleaning ability of Er:YAG laser against Enterococcus faecalis in root canals.  Methods: The single-rooted human teeth were sterilized and inoculated with Enterococcus faecalis and were randomly assigned into 2 groups. A group of teeth was irrigated with saline during root canal preparation while another group with NaClO. After mechanical preparation, the two groups were randomly divided into 3 subgroups according to the different treatments: Samples, laser radiation, and calcium hydroxide intracanal medication for 7 days. Bactericical effects were compared among groups. Root canal walls and dental tubules were observed under scanning electron microscope.  Results: Er:YAG laser was the most efficient way for anti-bacteria among the groups (P<0.05), but there was no significant difference between the 2 laser groups (P>0.05). Meanwhile the smear laser was efficiently removed by laser compared with other treatments, and the laser could open the dentinal tubules.  Conclusion: Er:YAG laser can be effectively used for root canal disinfection without NaClO and Ca(OH)2.
authors.affiliation: Department of Stomatology, Xiangya Hospital, Central South University, Changsha 410008, China.
authors.forename: Zongbo
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Stomatology, Xiangya Hospital, Central South University, Changsha 410008, China.
authors.forename: Changyun
authors.initials: C
authors.lastname: Fang
mesh_terms: D002122:Calcium Chloride; D003786:Dental Pulp Cavity / Q000382:microbiology*; D013293:Enterococcus faecalis / Q000528:radiation effects*; D006801:Humans; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D011897:Random Allocation; D018915:Root Canal Preparation / Q000379:methods*; D016369:Smear Layer / Q000628:therapy*; D007507:Therapeutic Irrigation
chemical_list: D002122:Calcium Chloride