Tooth sealing formulation with bacteria-killing surface and on-demand ion release/recharge inhibits early childhood caries key pathogens

J Biomed Mater Res B Appl Biomater. 2020 Nov;108(8):3217-3227. doi: 10.1002/jbm.b.34659. Epub 2020 Jun 29.

Abstract

Herein, we investigated a biointeractive tooth sealing material consisted of dimethylaminohexadecyl methacrylate (DMAHDM) and amorphous calcium phosphate nanoparticles (NACPs) to address the above issues simultaneously. Of note, 5% DMAHDM was incorporated into the resin blend, and 20% NACP was added to inorganic filler content of dental formulations intended as dental sealants. The sealing materials were used to seal human extracted teeth. The sealed teeth were subjected to an early childhood caries (ECC) key pathogen (Candida albicans and Streptococcus mutans) biofilm model using a dynamic caries tooth model (CDC reactor). The biofilm growth over the sealed teeth was assessed via colony-forming unit counting metabolic activity assays. The enamel surface hardness loss, degree of conversion, shear bond strength (SBS), and cytotoxicity were also investigated. Formulations having DMAHDM displayed antibacterial efficiency of 2.8-3.5 and 1.4-4.0 log inhibition for Streptococcus mutans and Candida albicans, respectively. Furthermore, the metabolic activity was reduced on the top of the sealed tooth with the biointeractive sealing materials (p < .05). The degree of conversion values was acceptable. The enamel surface hardness loss decreases (36 ± 9.8%) when in contact with the biointeractive tooth sealing material. The SBS of the combined formulation (5% DMAHDM + 20% NACP) was lower than commercial sealant but similar to experimental control. The investigated sealing material holds valuable dual antibacterial and antifungal activities associated with a reduced mineral loss against the cariogenic challenge promoted by ECC key pathogens.

Keywords: calcium phosphate nanoparticles; caries inhibition; dental materials; quaternary ammonium.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / administration & dosage*
  • Anti-Bacterial Agents / therapeutic use*
  • Biofilms / drug effects
  • Calcium Phosphates
  • Candida albicans / drug effects
  • Child
  • Colony Count, Microbial
  • Dental Caries / microbiology*
  • Dental Caries / prevention & control*
  • Dental Caries Susceptibility
  • Dental Enamel / drug effects
  • Drug Compounding
  • Humans
  • Methacrylates
  • Methylamines
  • Nanoparticles
  • Pit and Fissure Sealants*
  • Streptococcus mutans / drug effects
  • Tooth Remineralization

Substances

  • Anti-Bacterial Agents
  • Calcium Phosphates
  • Methacrylates
  • Methylamines
  • Pit and Fissure Sealants
  • dimethylaminohexadecyl methacrylate