title: Calcium hydroxide removal in curved root canals with apical transportation In Vitro.
abstract: Calcium hydroxide (CH) is applied to improve disinfection of root canals in most root canal retreatment. This study aimed to analyze the CH removal efficacy using 7 different root preparing files (K file, pre-curved K file, EndoActivator, Ultrasonic file, pre-curved ultrasonic file, F file and needle irrigation alone) with apical transportation. Standardized models of curved canal with such apical transportation or not were set up before applying CH to root canal for 7 days. Seven techniques described above were used for its removal. Then the roots were disassembled and digital photos were taken. The ratio of residual CH in the overall canal surface was calculated using the image analyzer image pro plus 6.0. The data were analyzed using one-way ANOVA with post hoc Tukey test. Results revealed that CH was effectively removed (P<0.05) by using all 6 mechanical methods except irrigation alone. In curved root canals with apical transportation, EndoActivator, pre-curved ultrasonic file and F file were found to be more effective in removing CH than the other four file (P<0.001), while there was no significant difference among EndoActivator, pre-curved ultrasonic file and F file groups (P>0.05). The percentage of residual CH in the canal with apical transportation was higher than that in the canal without apical transportation (P<0.05). In conclusion, CH can be hardly removed completely. Canal with apical transportation will result in insufficient CH removal. EndoActivator, pre-curved ultrasonic file and F file are more effective in the curved root canal with apical transportation.
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China.|Department of Conservation Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Song
authors.affiliation: Department of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
authors.forename: Jing-Zhi
authors.initials: JZ
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China.|Department of Conservation Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
authors.forename: Ru-Yan
authors.initials: RY
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China.|Department of Conservation Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
authors.forename: Xue-Dong
authors.initials: XD
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China.|Department of Conservation Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Zou
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China. gaoyuan@scu.edu.cn.|Department of Conservation Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China. gaoyuan@scu.edu.cn.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Gao
mesh_terms: D000818:Animals; D001843:Bone Cements / Q000494:pharmacology*; D002126:Calcium Hydroxide / Q000494:pharmacology*; D002417:Cattle; D003786:Dental Pulp Cavity; D004202:Disinfectants / Q000494:pharmacology*; D018915:Root Canal Preparation / Q000379:methods*
chemical_list: D001843:Bone Cements; D004202:Disinfectants; D002126:Calcium Hydroxide