title: Novel protein-repellent dental adhesive containing 2-methacryloyloxyethyl phosphorylcholine.
abstract: OBJECTIVE
  Biofilms at tooth-restoration margins can produce acids and cause secondary caries. A protein-repellent adhesive resin can potentially inhibit bacteria attachment and biofilm growth. However, there has been no report on protein-repellent dental resins. The objectives of this study were to develop a protein-repellent bonding agent incorporating 2-methacryloyloxyethyl phosphorylcholine (MPC), and to investigate its resistance to protein adsorption and biofilm growth for the first time.
  
  
  METHODS
  MPC was incorporated into Scotchbond Multi-Purpose (SBMP) at 0%, 3.75%, 7.5%, 11.25%, and 15% by mass. Extracted human teeth were used to measure dentine shear bond strengths. Protein adsorption onto resins was determined by a micro bicinchoninic acid (BCA) method. A dental plaque microcosm biofilm model with human saliva as inoculum was used to measure biofilm metabolic activity and colony-forming unit (CFU) counts.
  
  
  RESULTS
  Adding 7.5% MPC into primer and adhesive did not decrease the dentine bond strength, compared to control (p>0.1). Incorporation of 7.5% of MPC achieved the lowest protein adsorption, which was 20-fold less than that of control. Incorporation of 7.5% of MPC greatly reduced bacterial adhesion, yielding biofilm total microorganism, total streptococci, and mutans streptococci CFU that were an order of magnitude less than control.
  
  
  CONCLUSIONS
  A protein-repellent dental adhesive resin was developed for the first time. Incorporation of MPC into primer and adhesive at 7.5% by mass greatly reduced the protein adsorption and bacterial adhesion, without compromising the dentine bond strength.
  
  
  CONCLUSIONS
  The novel protein-repellent primer and adhesive are promising to inhibit biofilm formation and acid production, to protect the tooth-restoration margins and prevent secondary caries.
authors.affiliation: Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China; Biomaterials & Tissue Engineering Division, Department of Endodontics, Prosthodontics and Operative Dentistry, University of Maryland Dental School, Baltimore, MD 21201, USA.
authors.forename: Ning
authors.initials: N
authors.lastname: Zhang
authors.affiliation: Biomaterials & Tissue Engineering Division, Department of Endodontics, Prosthodontics and Operative Dentistry, University of Maryland Dental School, Baltimore, MD 21201, USA.
authors.forename: Mary Anne S
authors.initials: MA
authors.lastname: Melo
authors.affiliation: Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China. Electronic address: byuxing@263.net.
authors.forename: Yuxing
authors.initials: Y
authors.lastname: Bai
authors.affiliation: Biomaterials & Tissue Engineering Division, Department of Endodontics, Prosthodontics and Operative Dentistry, University of Maryland Dental School, Baltimore, MD 21201, USA; Center for Stem Cell Biology & Regenerative Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Mechanical Engineering, University of Maryland, Baltimore County, MD 21250, USA. Electronic address: hxu@umaryland.edu.
authors.forename: Hockin H K
authors.initials: HH
authors.lastname: Xu
mesh_terms: D000327:Adsorption; D001422:Bacterial Adhesion / Q000187:drug effects*; D058491:Bacterial Load / Q000187:drug effects; D001426:Bacterial Proteins / Q000187:drug effects; D018441:Biofilms / Q000187:drug effects*; D004396:Coloring Agents; D001840:Dental Bonding; D003773:Dental Plaque / Q000382:microbiology; D003804:Dentin / Q000648:ultrastructure; D006801:Humans; D007202:Indicators and Reagents; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry / Q000494:pharmacology*; D050296:Microbial Viability / Q000187:drug effects; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D011804:Quinolines; D019279:Resin Cements / Q000737:chemistry / Q000494:pharmacology*; D012463:Saliva / Q000382:microbiology; D033081:Shear Strength; D013295:Streptococcus mutans / Q000187:drug effects; D013499:Surface Properties; D013778:Tetrazolium Salts; D013844:Thiazoles
chemical_list: D001426:Bacterial Proteins; D004396:Coloring Agents; D007202:Indicators and Reagents; D008689:Methacrylates; D011804:Quinolines; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; D013778:Tetrazolium Salts; D013844:Thiazoles; D010767:Phosphorylcholine; C070638:2-methacryloyloxyethyl phosphorylcholine; C047117:bicinchoninic acid; C022616:thiazolyl blue
keywords: Bacteria repellent; Caries inhibition; Dental adhesive; Dentine bond strength; Human saliva microcosm biofilm; Protein repellent