Rechargeable microbial anti-adhesive polymethyl methacrylate incorporating silver sulfadiazine-loaded mesoporous silica nanocarriers

Dent Mater. 2017 Oct;33(10):e361-e372. doi: 10.1016/j.dental.2017.07.009. Epub 2017 Aug 1.

Abstract

Objectives: Even though polymethyl methacrylate (PMMA) resin is widely used as a dental material, it has poor microbial anti-adhesive properties, which accelerates oral infections. In this investigation, silver-sulfadiazine (AgSD)-loaded mesoporous silica nanoparticles (Ag-MSNs) were incorporated into PMMA to introduce long-term microbial anti-adhesive effects and to make PMMA a rechargeable resin.

Methods: After characterization of the Ag-MSNs in terms of their mesoporous characteristics and drug loading capacity, the 3 point flexural test and hardness were evaluated in PMMA incorporating Ag-MSNs (0.5, 1, 2.5 and 5%). Anti-adhesive effects were observed for Candida albicans and Streptococcus oralis with experimental specimens for up to 28days and after recharging with AgSD.

Results: A typical spherical morphology and high mesoporosity were observed for the MSNs used for loading AgSD. Incorporation of Ag-MSNs into PMMA (0.5, 1, 2.5 and 5%) sustained its flexural strength but increased its surface hardness. Anti-adhesive effects were observed after 1h of exposure to both microbial species, and the effects accelerated with increasing Ag-MSN incorporation into PMMA. Long-term microbial anti-adhesive effects were observed for up to 14 days, and further long-term (7 days) anti-adhesive effects were observed after reloading the Ag-MSN-incorporated PMMA (aged for 28 days) with AgSD; these effects were largely caused by released silver ions and partially by changes in surface hydrophilicity. No cytotoxicity to keratinocytes was observed.

Conclusions: The improved mechanical properties and the prolonged microbial anti-adhesive effects, which lasted after reloading of the drug, suggest the potential usefulness of Ag-MSN-incorporated PMMA as a microbial anti-adhesive dental material.

Significance: Ag-MSN-incorporated PMMA can be used as a microbial anti-adhesive dental material for dentures, orthodontic devices and provisional restorative materials.

Keywords: Long-term microbial anti-adhesive effect; Mesoporous nanocarriers; PMMA; Reloadable; Silver-sulfadiazine.

MeSH terms

  • Dental Cements*
  • Materials Testing
  • Polymethyl Methacrylate*
  • Silicon Dioxide
  • Silver Sulfadiazine*

Substances

  • Dental Cements
  • Silicon Dioxide
  • Polymethyl Methacrylate
  • Silver Sulfadiazine