Novel dental resin infiltrant containing smart monomer dodecylmethylaminoethyl methacrylate

Abstract

ObjectivesWhite spot lesions (WSLs) are prevalent and often lead to aesthetic problems and progressive caries. The objectives of this study were to: (1) develop a novel resin infiltrant containing smart monomer dodecylmethylaminoethyl methacrylate (DMAEM) to inhibit WSLs, and (2) investigate the effects of DMAEM incorporation on cytotoxicity, mechanical properties, biofilm-inhibition and protection of enamel hardness for the first time.MethodsDMAEM was synthesized using 1-bromododecane, 2-methylamino ethanol and methylmethacrylate. DMAEM with mass fractions of 0%, 1.25%, 2.5% and 5% were incorporated into a resin infiltant containing BisGMA and TEGDMA. Cytotoxicity, mechanical properties and antibacterial effects were tested. After resin infiltration, bovine enamel was demineralized with saliva biofilm acids, and enamel hardness was measured.ResultDMAEM infiltration did not increase the cytotoxicity or compromise the physical properties when DMAEM mass fraction was below 5% (p > 0.05). Biofilm metabolic activity was reduced by 90%, and biofilm lactic acid production was reduced by 92%, via DMAEM (p < 0.05). Mutans streptococci biofilm CFU was reduced by 3 logs (p < 0.05). When demineralized in acid and then under biofilms, the infiltrant + 5% DMAEM group produced an enamel hardness (mean ± sd; n = 6) of 2.90 ± 0.06 GPa, much higher than 0.85 ± 0.12 GPa of the infiltrant + 0% DMAEM group (p < 0.05).SignificanceA novel resin infiltrant with excellent mechanical properties, biocompability, strong antibacterial activity and anti-demineralization effect was developed using DMAEM for the first time. The DMAEM resin infiltrant is promising for inhibiting WSLs, arresting early caries, and protecting enamel hardness.

Recent Advances in Quaternary Ammonium Monomers for Dental Applications

“…In addition, the acid generated by the acidogenic bacteria causes the pH to drop below 5.5 during the development of caries [87,88]. Therefore, the "smart" monomer with reversible pH response will be the ideal antibacterial agent for dental resin composites [50,89].…”

“…Additional research was conducted to investigate the ability of resin infiltrate-containing DMAEM to prevent white spot lesions (WSLs). The incorporation of DMAEM was successful in preventing WSLs, stopping early caries, and protecting enamel hardness [89]. The novel smart monomers are highly promising for application in antibacterial dental resin composites.…”

Smart Dental Materials Intelligently Responding to Oral pH to Combat Caries: A Literature Review

“…DMAEM was also used to develop new resin infiltrates to treat white spot lesions. Huang et al developed a new smart resin infiltrate containing DMAEM, which protected tooth enamel against acid attack, making it significantly harder than the commercial control group [ 45 ].…”