Evaluation physical characteristics and comparison antimicrobial and anti-inflammation potentials of dental root canal sealers containing hinokitiol in vitro

PLoS One. 2014 Jun 10;9(6):e94941. doi: 10.1371/journal.pone.0094941. eCollection 2014.

Abstract

Hinokitiol displays potent antimicrobial activity. It has been used in toothpaste and oral-care gel to improve the oral lichen planus and reduce halitosis. The aim of this study was to evaluate the antimicrobial activity of 3 different dental root canal sealers with hinokitiol (sealers+H) and their physical and biological effects. AH Plus (epoxy amine resin-based, AH), Apexit Plus (calcium-hydroxide-based, AP), and Canals (zinc-oxide-eugenol-based, CA), were used in this study. The original AH and CA exhibited strong anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity, but AP did not. The setting time, working time, flowability, film thickness, and solubility of each sealer+0.2%H complied with ISO 6876:2001. CA+0.2%H exhibited high cytotoxicity, but the others sealers+0.2%H did not. Because hinokitiol combined with Zn2+ in CA creates a synergistic effect. The physical tests of AP+0.5%-1%H complied with ISO 6876:2001, improved antimicrobial activity, inhibited inflammation genes cyclooxygenase-2 (COX-2) and hypoxia-inducible factor-1α (HIF-1α) mRNA in MG-63 cells and human gingival fibroblasts (HGF), and down-regulated lysyl oxidase (LOX) mRNA of HGF. In summary, AH and CA demonstrated strong antimicrobial activity, but AP did not. Application of hinokitiol increases AH anti-MRSA activity should less than 0.2% for keep well flowability. AP+0.5%-1% hinokitiol exhibited strong physical, antibacterial, and anti-inflammation potentials, and inhibited S. aureus abscess formation. Applying an appreciable proportion of hinokitiol to epoxy-amine-resin-based and calcium-hydroxide-based root canal sealers is warranted, but the enhanced cytotoxicity and synergistic effect must be considered.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aggregatibacter actinomycetemcomitans / drug effects
  • Anti-Infective Agents / chemistry
  • Anti-Infective Agents / pharmacology*
  • Cells, Cultured
  • Cyclooxygenase 2 / genetics
  • Cyclooxygenase 2 / metabolism
  • Fibroblasts / drug effects
  • Fibroblasts / metabolism
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism
  • Methicillin-Resistant Staphylococcus aureus / drug effects
  • Monoterpenes / chemistry
  • Monoterpenes / pharmacology*
  • Pit and Fissure Sealants / chemistry
  • Pit and Fissure Sealants / pharmacology*
  • Protein-Lysine 6-Oxidase / genetics
  • Protein-Lysine 6-Oxidase / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Root Canal Filling Materials / chemistry
  • Root Canal Filling Materials / pharmacology*
  • Streptococcus mutans / drug effects
  • Tropolone / analogs & derivatives*
  • Tropolone / chemistry
  • Tropolone / pharmacology

Substances

  • Anti-Infective Agents
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Monoterpenes
  • Pit and Fissure Sealants
  • RNA, Messenger
  • Root Canal Filling Materials
  • Tropolone
  • Cyclooxygenase 2
  • Protein-Lysine 6-Oxidase
  • beta-thujaplicin

Grants and funding

This study was supported by research grants NSC 99-2314-B-039-023-MY3 from the National Science Council, CMU98-N1-30 from the China Medical University, and Taiwan Ministry of Health and Welfare Clinical Trial and Research Center of Excellence (DOH102-TD-B-111-004). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.