title: Chlorhexidine binding to mineralized versus demineralized dentin powder.
abstract: OBJECTIVE
  The purposes of this work were to quantitate the affinity and binding capacity of chlorhexidine (CHX) digluconate to mineralized versus demineralized dentin powder and to determine how much debinding would result from rinsing with water, ethanol, hydroxyethylmethacrylate (HEMA) or 0.5M NaCl in water.
  
  
  METHODS
  Dentin powder was made from coronal dentin of extracted human third molars. Standard amounts of dentin powder were tumbled with increasing concentrations of CHX (0-30 mM) for 30 min at 37 degrees C. After centrifuging the tubes, the supernatant was removed and the decrease in CHX concentration quantitated by UV-spectroscopy. CHX-treated dentin powder was resuspended in one of the four debinding solutions for 3 min. The amount of debound CHX in the solvents was also quantitated by UV-spectroscopy.
  
  
  RESULTS
  As the CHX concentration in the medium increased, the CHX binding to mineralized dentin powder also increased up to 6.8 micromol/g of dry dentin powder. Demineralized dentin powder took up significantly (p<0.01) more CHX, reaching 30.1 micromol CHX/g of dry dentin powder. Debinding of CHX was in the order: HEMA<ethanol<0.05 M NaCl<water. The highest CHX binding to demineralized dentin occurred at 30 mM (1.5 wt.%).
  
  
  CONCLUSIONS
  As CHX is not debound by HEMA, it may remain bound to demineralized dentin during resin-dentin bonding. This may be responsible for the long-term efficacy of CHX as an MMP inhibitor in resin-dentin bonds.
authors.affiliation: Department of Conservative Dentistry, School of Dentistry, Kyung Hee National University, Seoul, Republic of Korea.
authors.forename: Jongryul
authors.initials: J
authors.lastname: Kim
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Uchiyama
authors.forename: Marcela
authors.initials: M
authors.lastname: Carrilho
authors.forename: Kelli A
authors.initials: KA
authors.lastname: Agee
authors.forename: Annalisa
authors.initials: A
authors.lastname: Mazzoni
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Breschi
authors.forename: Ricardo M
authors.initials: RM
authors.lastname: Carvalho
authors.forename: Leo
authors.initials: L
authors.lastname: Tjäderhane
authors.forename: Stephen
authors.initials: S
authors.lastname: Looney
authors.forename: Courtney
authors.initials: C
authors.lastname: Wimmer
authors.forename: Arzu
authors.initials: A
authors.lastname: Tezvergil-Mutluay
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
authors.forename: David H
authors.initials: DH
authors.lastname: Pashley
mesh_terms: D000891:Anti-Infective Agents, Local / Q000493:pharmacokinetics* / Q000494:pharmacology; D002710:Chlorhexidine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000494:pharmacology; D003094:Collagen / Q000378:metabolism; D001840:Dental Bonding; D003804:Dentin / Q000378:metabolism*; D017886:Durapatite; D000431:Ethanol; D006801:Humans; D006860:Hydrogen Bonding; D016014:Linear Models; D061965:Matrix Metalloproteinase Inhibitors; D008689:Methacrylates; D011480:Protease Inhibitors / Q000494:pharmacology; D011485:Protein Binding; D019279:Resin Cements / Q000737:chemistry; D012965:Sodium Chloride; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D017001:Tooth Demineralization / Q000378:metabolism*; D014867:Water
chemical_list: D000891:Anti-Infective Agents, Local; D061965:Matrix Metalloproteinase Inhibitors; D008689:Methacrylates; D011480:Protease Inhibitors; D019279:Resin Cements; D014867:Water; D000431:Ethanol; D012965:Sodium Chloride; C005044:hydroxyethyl methacrylate; D003094:Collagen; D017886:Durapatite; C010882:chlorhexidine gluconate; D002710:Chlorhexidine
references.citation: J Endod. 2009 May;35(5):686-9
references.pmid: 19410083
references.citation: Dent Mater. 1997 Jan;13(1):24-33
references.pmid: 9467320
references.citation: J Dent Res. 2005 Aug;84(8):741-6
references.pmid: 16040733
references.citation: J Biomed Mater Res A. 2003 Dec 1;67(3):900-7
references.pmid: 14613238
references.citation: J Biomed Mater Res B Appl Biomater. 2007 Jan;80(1):156-65
references.pmid: 16680696
references.citation: Monogr Oral Sci. 1991;15:1-201
references.pmid: 1870604
references.citation: J Phys Chem B. 2007 Aug 2;111(30):8775-84
references.pmid: 17602516
references.citation: Biopolymers. 1988 Nov;27(11):1749-60
references.pmid: 3233328
references.citation: J Adhes Dent. 2003 Summer;5(2):129-38
references.pmid: 14964680
references.citation: Arch Oral Biol. 2000 Sep;45(9):757-65
references.pmid: 10869489
references.citation: Arch Oral Biol. 1990;35(9):731-9
references.pmid: 2091592
references.citation: Arch Oral Biol. 2007 Feb;52(2):121-7
references.pmid: 17045563
references.citation: J Dent Res. 2007 May;86(5):436-40
references.pmid: 17452564
references.citation: J Dent Res. 2004 Mar;83(3):216-21
references.pmid: 14981122
references.citation: J Dent Res. 2008 Sep;87(9):829-33
references.pmid: 18719208
references.citation: Arch Oral Biol. 1996 Apr;41(4):379-86
references.pmid: 8771329
references.citation: Dent Mater. 2008 Oct;24(10):1391-9
references.pmid: 18439668
references.citation: Int Endod J. 2009 Apr;42(4):288-302
references.pmid: 19220510
references.citation: J Biomed Mater Res A. 2006 Nov;79(2):349-58
references.pmid: 16883589
references.citation: J Dent Res. 2006 Oct;85(10):950-4
references.pmid: 16998139
references.citation: J Biomed Mater Res. 2001 Aug;56(2):273-81
references.pmid: 11340599
references.citation: J Dent Res. 2007 Jun;86(6):529-33
references.pmid: 17525352
references.citation: Am J Dent. 2007 Feb;20(1):7-20
references.pmid: 17380802
references.citation: Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2004 Oct;98(4):488-92
references.pmid: 15472666
references.citation: Biomaterials. 2005 Dec;26(34):7145-53
references.pmid: 15955557
references.citation: Clin Diagn Lab Immunol. 1999 May;6(3):437-9
references.pmid: 10225852
references.citation: Oper Dent. 2007 Mar-Apr;32(2):107-11
references.pmid: 17427817
references.citation: J Dent Res. 2003 Aug;82(8):597-601
references.pmid: 12885842
references.citation: Oper Dent. 2009 Jul-Aug;34(4):379-83
references.pmid: 19678441