title: Quantitative Evaluation of MDP-Ca Salt and DCPD after Application of an MDP-based One-step Self-etching Adhesive on Enamel and Dentin.
abstract: OBJECTIVE
  To investigate the effects of an experimental 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-based one-step self-etching adhesive (EX adhesive) applied to enamel and dentin on the production of calcium salt of MDP (MDP-Ca salt) and dicalcium phosphate dehydrate (DCPD) at various periods.
  
  
  METHODS
  The EX adhesive was prepared. Bovine enamel and dentin reactants were prepared by varying the application period of the EX adhesive: 0.5, 1, 5, 30, 60 and 1440 min. Enamel and dentin reactants were analyzed using x-ray diffraction and solid-state phosphorus-31 nuclear magnetic resonance (31P NMR). Curvefitting analyses of corresponding 31P NMR spectra were performed.
  
  
  RESULTS
  Enamel and dentin developed several types of MDP-Ca salts and DCPDs with amorphous and crystalline phases throughout the application period. The predominant molecular species of MDP-Ca salt was determined as the monocalcium salt of the MDP monomer. Dentin showed a faster production rate and greater produced amounts of MDP-Ca salt than did enamel, since enamel showed a knee-point in the production rate of the MDP-Ca salt at the application period of 5 min. In contrast, enamel developed greater amounts of DCPD than did dentin and two types of DCPDs with different crystalline phases at application periods > 30 min. The amounts of MDP-Ca salt developed during the 30-s application of the EX adhesive on enamel and dentin were 7.3 times and 21.2 times greater than DCPD, respectively.
  
  
  CONCLUSIONS
  The MDP-based one-step adhesive yielded several types of MDP-Ca salts and DCPD with an amorphous phase during the 30-s application period on enamel and dentin.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yokota
authors.forename: Kou Nakajima
authors.initials: KN
authors.lastname: Fujita
authors.forename: Ryoichiro
authors.initials: R
authors.lastname: Uchida
authors.forename: Etsuko
authors.initials: E
authors.lastname: Aida
authors.forename: Naoko Tabei
authors.initials: NT
authors.lastname: Aoki
authors.forename: Masahiro
authors.initials: M
authors.lastname: Aida
authors.forename: Norihiro
authors.initials: N
authors.lastname: Nishiyama
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000818:Animals; D017610:Calcium Compounds / Q000032:analysis / Q000737:chemistry*; D002130:Calcium Phosphates / Q000032:analysis / Q000737:chemistry*; D002417:Cattle; D003460:Crystallization; D003743:Dental Enamel / Q000737:chemistry / Q000648:ultrastructure*; D003804:Dentin / Q000737:chemistry / Q000648:ultrastructure*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008422:Materials Testing; D008689:Methacrylates / Q000032:analysis / Q000737:chemistry*; D010759:Phosphorus Isotopes; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D013997:Time Factors; D014961:X-Ray Diffraction / Q000379:methods
chemical_list: D017610:Calcium Compounds; D002130:Calcium Phosphates; D008689:Methacrylates; D010759:Phosphorus Isotopes; D011109:Polymethacrylic Acids; D011140:Polyurethanes; D019279:Resin Cements; C029824:urethane dimethacrylate luting resin; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; C034139:4-methacryloxyethyltrimellitic acid anhydride; C069749:methacryloyloxydecyl dihydrogen phosphate; C494366:calcium phosphate, dibasic, dihydrate