A Novel Dental Sealant Containing Dimethylaminohexadecyl Methacrylate Suppresses the Cariogenic Pathogenicity of Streptococcus mutans Biofilms

Abstract

Cariogenic oral biofilms are strongly linked to dental caries around dental sealants. Quaternary ammonium monomers copolymerized with dental resin systems have been increasingly explored for modulation of biofilm growth. Here, we investigated the effect of dimethylaminohexadecyl methacrylate (DMAHDM) on the cariogenic pathogenicity of Streptococcus mutans (S. mutans) biofilms. DMAHDM at 5 mass% was incorporated into a parental formulation containing 20 mass% nanoparticles of amorphous calcium phosphate (NACP). S. mutans biofilms were grown on the formulations, and biofilm inhibition and virulence properties were assessed. The tolerances to acid stress and hydrogen peroxide stress were also evaluated. Our findings suggest that incorporating 5% DMAHDM into 20% NACP-containing sealants (1) imparts a detrimental biological effect on S. mutans by reducing colony-forming unit counts, metabolic activity and exopolysaccharide synthesis; and (2) reduces overall acid production and tolerance to oxygen stress, two major virulence factors of this microorganism. These results provide a perspective on the value of integrating bioactive restorative materials with traditional caries management approaches in clinical practice. Contact-killing strategies via dental materials aiming to prevent or at least reduce high numbers of cariogenic bacteria may be a promising approach to decrease caries in patients at high risk.

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

“…The present findings are in agreement with other studies to some degree since this is a first‐time investigation on coculture of S. mutans and C. albicans . For S. mutans biofilm formation, the substantial 3–4 log reduction for biofilm growth over DMAHDM confirms previous in vitro studies regarding the antimicrobial activity of DMAHDM with concentration variation from 3% to 5% (Ibrahim et al, 2019; Wang et al, 2018).…”

“…We have reported screened formulations that reach acceptable rates for physical and mechanical properties using DMAHDM and amorphous calcium phosphate nanoparticles (NACPs), respectively (Ibrahim et al, 2018). Furthermore, we have suggested a role of DMAHDM in the reduction of S. mutans virulence factors (Ibrahim et al, 2019). Concerning the incorporation of nanosized amorphous calcium phosphate, a high rate of calcium and phosphate ions release was observed over 2months, and the recharge of the ions and subsequent release were successfully reached with this biointeractive tooth sealing formulation (Al‐Dulaijan et al, 2018; Al‐Qarni et al, 2018).…”

Dental Sealant Empowered by 1,3,5-Tri Acryloyl Hexahydro-1,3,5-Triazine and α-Tricalcium Phosphate for Anti-Caries Application

“…QACs have been studied due to their high and broad antibacterial spectra, even at small concentrations [25][26][27]. In the case of TAT, it was suggested that the mechanism of antibacterial action is due to "contact killing" effect [6].…”

Novel Crown Cement Containing Antibacterial Monomer and Calcium Phosphate Nanoparticles

“…In recent studies, DMAHDM was incorporated into resin-based materials and exhibited an excellent antimicrobial activity [ 25 , 26 , 27 ]. It has been reported that DMAHDM is a positively charged monomer with the ability to work through direct contact killing mechanisms by interacting with negatively charged bacterial cell membranes, causing bacterial cell disturbance and lysis [ 28 , 29 ].…”

“…DMAHDM and NACP were incorporated into dental adhesives, pit and fissure sealants, and resin composites in previous studies. They presented strong antibacterial outcomes with a high level of Ca 2+ and PO 4 3− ion release [ 20 , 25 , 30 , 31 ]. Consequently, the incorporation of DMAHDM and NACP into a resin-based material could help to prevent dental caries through DMAHDM contact inhibition action and tooth remineralization through the release of Ca 2+ and PO 4 3− ions into the tooth-restoration interface [ 25 , 32 ].…”