title: [The effect of calcium hydroxide on IL-6 and TNF-α expression of osteoblast in periapical tissues].
abstract: OBJECTIVE
  To compare the effect of calcium hydroxide in different position on pH and inflammation factor expression of periapical osteoblasts.
  
  
  METHODS
  140 sterilized single-rooted human teeth models were randomly divided into 6 experiment groups and one control group: Group 1-3:calcium hydroxide paste was placed in the apical half of root canal, the upper half of root canal and the pulp champer; Group 4-6:Apexcal was placed in the apical half of root canal, the upper half of root canal and the pulp champer; Group 7: the control group without medication. 10 teeth of each group were placed in P.e suspension, the IL-6 and TNF-α expression of MC3T3-E1 was tested at 3 d and 7 d. The other teeth of each group were placed in distilled water, and the pH in periapical region was tested at 3, 7, 14 and 21 d. SPSS 13.0 software package was used for statistical analysis.
  
  
  RESULTS
  Calcium hydroxide placed in different position of the root canal increased periapical pH value and reached its peak at 14 d. The group in which calcium hydroxide paste was placed in pulp chamber gained lower pH level than other experimental groups. IL-6, TNF-α expression of MC3T3-E1 pretreated by P.e suspension of experimental groups was significantly reduced compared with control group, and there was no significant difference between the experimental groups.
  
  
  CONCLUSIONS
  Calcium hydroxide placed in different position of the root canal could increase periapical pH value and reduce IL- 6, TNF-α expression of periapical osteoblasts.
authors.affiliation: Department of Endodontics, School of Stomatology, China Medical University; Liaoning Institute of Dental Research; Liaoning Key Laboratory of Oral Diseases and Research Center of Oral Disease Translational Medicine. Shenyang 110002, Liaoning Province, China. E-mail:yjswz999@163.com.
authors.forename: Ling-jiao
authors.initials: LJ
authors.lastname: Meng
authors.affiliation: Department of Endodontics, School of Stomatology, China Medical University; Liaoning Institute of Dental Research; Liaoning Key Laboratory of Oral Diseases and Research Center of Oral Disease Translational Medicine. Shenyang 110002, Liaoning Province, China.
authors.forename: Li-hong
authors.initials: LH
authors.lastname: Qiu
authors.affiliation: Department of Endodontics, School of Stomatology, China Medical University; Liaoning Institute of Dental Research; Liaoning Key Laboratory of Oral Diseases and Research Center of Oral Disease Translational Medicine. Shenyang 110002, Liaoning Province, China.
authors.forename: Ya-qiong
authors.initials: YQ
authors.lastname: Yu
authors.affiliation: Department of Endodontics, School of Stomatology, China Medical University; Liaoning Institute of Dental Research; Liaoning Key Laboratory of Oral Diseases and Research Center of Oral Disease Translational Medicine. Shenyang 110002, Liaoning Province, China. E-mail:yjswz999@163.com.
authors.forename: Fu-liang
authors.initials: FL
authors.lastname: Zhan
authors.affiliation: Department of Endodontics, School of Stomatology, China Medical University; Liaoning Institute of Dental Research; Liaoning Key Laboratory of Oral Diseases and Research Center of Oral Disease Translational Medicine. Shenyang 110002, Liaoning Province, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Endodontics, School of Stomatology, China Medical University; Liaoning Institute of Dental Research; Liaoning Key Laboratory of Oral Diseases and Research Center of Oral Disease Translational Medicine. Shenyang 110002, Liaoning Province, China.
authors.forename: Xiao-fang
authors.initials: XF
authors.lastname: Zhang
mesh_terms: D002126:Calcium Hydroxide / Q000494:pharmacology*; D003782:Dental Pulp; D003786:Dental Pulp Cavity; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism*; D010006:Osteoblasts / Q000378:metabolism*; D010486:Periapical Tissue / Q000378:metabolism*; D012387:Root Canal Filling Materials; D012390:Root Canal Therapy; D014092:Tooth Root; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
chemical_list: C546890:ApexCal; D015850:Interleukin-6; D012387:Root Canal Filling Materials; D014409:Tumor Necrosis Factor-alpha; D002126:Calcium Hydroxide