# Antibacterialarial Agents Used in Modifications of Dental Resin Composites: A Systematic Review
## 4 Discussion
### Modification of RBC Compositions
#### 4.2.1 Organic Compounds and Monomers
[32] decided to investigate the use of MDPB and different methacrylamide-based QACs as antimicrobial agents in a resin formulation. Such modifications significantly reduced the activity of _Streptococcus mutans_ and _Enterococcus faecalis_. Worth further study is the monomer 1-(11-Methacryla-midoundecyl) pyridine-1-ium bromide (MAUPB). Studies on the properties of composites enriched with these monomers should be continued. Because of MDPB's color ficklessness, [PERSON] et al. proposed another alternative, ionic dimethacrylates (IDMAs), which also exhibit antibacterial properties [68]. In the cited research, IDMA1 (2-(methacryloxy)-N-(2-(methacryloxy)ethyl)-N,N-dimethylethane-1-amine bromide) and IDMA2 (N,N'-([1,1'-biphenyl]-2,2'-diylbis (methylene)) bis(2-methacryloyloxy)-N,N-dimethylethan-1-aminium) bromide) were synthesized. The study showed that using IDMA increased the conversion rate of the material used without affecting its wettability. Material prepared with IDMA showed little or no toxicity to cells. The addition of IDMA as a comonomer reduces the flexural strength and modulus of elasticity of polymers. Only neat materials were evaluated in the study; no information about filled resin properties was provided. [PERSON] et al. [33] introduced myristyltrimethylammonium bromide (MYTAB) to composites at concentrations of 0.5, 1, and 2 wt%. Antimicrobial activity against _Streptococcus mutans_ was tested by two in vitro evaluations--against planktonic bacteria and biofilm formation--on cured material samples. The study showed that the composite material  
Figure 7: Methacryloyloxydodecylpyridinium bromide (MDPB). enriched with 2 wt% significantly reduced the abundance of _Streptococcus mutans_ in the planktonic and biofilm stages compared to the control sample and had no effect on the material's tensile strength or its conversion factor. Cytotoxicity was found to increase with increasing MYTAB concentration. The increase in cytotoxicity with increasing concentrations of the MYTAB modifier raises concerns about the safety of the experimental composite material. Further research is needed to resolve the cytotoxicity issue. Due to the use of quaternary ammonium compounds, an analysis of cytotoxicity should be performed. The long-term biocidal efficiency, the stability of the mechanical properties, and the water sorption of materials modified with this type of substance should be examined as well. [PERSON] et al. [34] studied the addition of resins containing 2.5 or 5 wt% of the monomer 1,3,5-triacryloylhexahydro-1,3,5-triazine methacrylate (TAT). There were no discernible differences noted in terms of the degree of conversion; the incorporation of TAT at a 5 wt% led to increased Knoop hardness, enhanced resistance to solvent softening, and higher ultimate tensile strength. Elevated concentrations of TAT correlated with heightened antibacterial activity. It was found that the application of TAT modification at 2.5% \(w/w\) showed no cytotoxicity compared with the control sample. In contrast, a 5% \(w/w\) TAT concentration resulted in reduced cell viability. Similarly to an earlier study, only resin formulations were evaluated. Other studies on the use of TAT in composites are necessary and should include long-term durability and cytotoxicity evaluations. Another option for reducing _Streptococcus mutans_ bacteria is the use of composite materials enriched with methacylated chitosan (CH-MA). [PERSON] et al. have shown that the use of CH-MA modifications reduces biofilm formation. However, it should be noted that the higher the amount of CH-MA, the lower the flexural strength and hardness of the composite [35]. [PERSON] et al. [36] used Trirazolium/POSS, which serves as an effective bactericidal additive to composites based on a ternary formulation of thiol-allyl ether and methacrylate. The results of the study showed that, despite a partial increase in the water absorption of the sample containing Triazolam/POSS, this parameter was more favorable compared to that of a composite made with DMAEMA-BC.