title: The biological performance of calcium hydroxide-loaded microcapsules.
abstract: BACKGROUND
  Calcium hydroxide (Ca[OH]2) microcapsules were synthesized for use in controlled release. The aim of this study was to evaluate the cytotoxicity, antibacterial properties, and influence on gene expression of bone-related markers of 2 different formulas of Ca(OH)2 microcapsules.
  
  
  METHODS
  Two formulas of Ca(OH)2 microcapsules (A and B) were evaluated, and pure Ca(OH)2 powder was used as a positive control. The shell material of formula A was pure EC, and the PLA/EC blend of 1:1 was used as the shell material for formula B. The MG63 cells/Cell Counting Kit-8 (Dojindo, Kumamoto, Japan) were used to evaluate the cytotoxicity, and the colony-forming units of Enterococcus faecalis were monitored for the antibacterial effect. The relative messenger RNA expression of collagen I and osteocalcin was determined by real-time polymerase chain reaction.
  
  
  RESULTS
  Both formulas of the Ca(OH)2 microcapsules showed no cytotoxicity in MG63 cells; however, the Ca(OH)2 positive control did exhibit cytotoxicity. The antibacterial effect of the 2 microcapsule formulas lasted longer than the positive control, and formula A lasted longer than formula B. For both Ca(OH)2 microcapsule formulas, the relative messenger RNA expression of collagen I and osteocalcin was prolonged and up-regulated. The time effects of the influence on messenger RNA expression of collagen I and osteocalcin were different between the 2 microcapsule formulas.
  
  
  CONCLUSIONS
  Ca(OH)2 microcapsules had prolonged antibacterial activity and prolonged the up-regulation of bone-related markers with reduced cytotoxicity.
authors.affiliation: Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Han
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Wang
authors.forename: Jiguang
authors.initials: J
authors.lastname: Liu
authors.forename: Fuxin
authors.initials: F
authors.lastname: Liang
authors.forename: Xiaozhong
authors.initials: X
authors.lastname: Qu
authors.forename: Zhenzhong
authors.initials: Z
authors.lastname: Yang
authors.forename: Xuejun
authors.initials: X
authors.lastname: Gao
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D002126:Calcium Hydroxide / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D002214:Capsules; D018929:Cell Culture Techniques; D045744:Cell Line, Tumor; D002482:Cellulose / Q000031:analogs & derivatives / Q000737:chemistry; D002626:Chemistry, Pharmaceutical; D024042:Collagen Type I / Q000187:drug effects; D003692:Delayed-Action Preparations; D013293:Enterococcus faecalis / Q000187:drug effects; D006801:Humans; D008422:Materials Testing; D010006:Osteoblasts / Q000187:drug effects; D015675:Osteocalcin / Q000187:drug effects; D011091:Polyesters / Q000737:chemistry; D012388:Root Canal Irrigants / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D013997:Time Factors; D015854:Up-Regulation
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D002214:Capsules; D024042:Collagen Type I; D003692:Delayed-Action Preparations; D011091:Polyesters; D012388:Root Canal Irrigants; D015675:Osteocalcin; C033616:poly(lactide); C013517:ethyl cellulose; D002482:Cellulose; D002126:Calcium Hydroxide
keywords: Biological performance; calcium hydroxide; controlled release; microcapsules; sustained release