Protein-repelling adhesive resin containing calcium phosphate nanoparticles with repeated ion-recharge and re-releases

J Dent. 2018 Nov:78:91-99. doi: 10.1016/j.jdent.2018.08.011. Epub 2018 Aug 25.

Abstract

Objectives: The objectives were to develop a calcium (Ca) and phosphate (P) ion-rechargeable and protein-repellent adhesive containing nanoparticles of amorphous calcium phosphate (NACP) and 2-methacryloyloxyethyl phosphorylcholine (MPC), and investigate the MPC effects on ion recharge and re-releases for the first time.

Methods: Pyromellitic glycerol dimethacrylate and ethoxylated bisphenol-A dimethacrylate were used to fabricate adhesive PEHB. Six adhesives were tested: (1) Scotchbond (SBMP); (2) PEHB, (3) PEHB + 20%NACP; (4) PEHB + 30%NACP; (5) PEHB + 20%NACP+3%MPC; (6) PEHB + 30%NACP+3%MPC. Dentin shear bond strength, Ca/P ion release, recharge and re-release, and protein adsorption were measured. A microcosm biofilm model was tested for lactic-acid production and colony-forming units (CFU).

Results: Adding NACP + MPC did not negatively affect dentin bond strength (p > 0.1). With increasing the number of recharge/re-release cycles, the Ca/P ion re-release reached similarly higher levels (p > 0.1), indicating long-term remineralization capability. One recharge enabled the adhesives to have continued re-releases for 21 days. Incorporation of 3% MPC yielded 10-fold decrease in protein adsorption, and 1-2 log decrease in biofilm CFU.

Conclusions: The new rechargeable adhesive with MPC + 30%NACP greatly reduced protein adsorption, biofilm growth and lactic acid. Incorporation of MPC did not compromise the excellent Ca/P ion release, rechargeability, and dentin bond strength.

Clinical significance: Novel bioactive adhesive containing MPC + NACP is promising to repel proteins and bacteria, and inhibit secondary caries at the restoration margins. The method of NACP + MPC to combine CaP-recharge and protein-repellency is applicable to the development of a new generation of materials including composites and cements to suppress oral biofilms and plaque formation and protect tooth structures.

Keywords: Calcium phosphate nanoparticles; Dental adhesive; Dentin bonding; Ion recharge; Protein adsorption; Secondary caries.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacteria / drug effects
  • Biofilms / drug effects
  • Calcium Phosphates* / chemistry
  • Calcium Phosphates* / pharmacology
  • Dental Cements* / chemistry
  • Dental Cements* / pharmacology
  • Ions* / chemistry
  • Materials Testing
  • Methacrylates / chemistry
  • Methacrylates / pharmacology
  • Nanoparticles* / chemistry

Substances

  • Anti-Bacterial Agents
  • Calcium Phosphates
  • Dental Cements
  • Ions
  • Methacrylates