**7. Conclusions**

Protein-repellent technology has the potential to decrease the global burden of dental caries. When incorporated into composites alone or with QAC monomers, protein-repellent technology can inhibit the adsorption of proteins onto dental materials and thus slow the formation of biofilm and associated oral diseases. Many research groups have contributed to the understanding of protein adsorption and material design, and it is now time for dental material researchers to make an impact in the clinical setting. A concerted e ffort should be placed on understanding the long-term effect on the oral microflora with protein-repellent restorations, as it is not ideal to remove "good" bacteria from the oral cavity. New, more design-driven monomers should be explored to enhance the stability and protein repellency of QAC restorations, to allow for prolonged antimicrobial properties. Last, the dental material field should unify in using reliable protein-adsorption protocols, to ensure consistent comparisons across di fferent material platforms.

**Author Contributions:** L.T.J. and D.R.B. contributed to the preparation/review of this manuscript. All authors have read and agreed to the published version of the manuscript.

**Funding:** This study was supported in part by the National Institute for Dental and Craniofacial Research (grants R01 DE26122 and DE026122-04S1) and the American Dental Association.

**Conflicts of Interest:** The authors declare no conflict of interest.

**Disclaimer:** The sole purpose of identifying certain commercial materials and equipment in this article was to adequately define the experimental protocols. Such identification, in no instance, implies recommendation or endorsement by the ADA or ADA Science & Research Institute, LLC, or means that the material/equipment specified is the best available for the purpose.
