The Impact of Dimethylaminohexadecyl Methacrylates on the Physical and Antibacterial Properties of Endodontic Sealers

Abdulrahman A. Balhaddad ^1* Faisal Alharamlah ¹ Fawaz Altuwaijri ² Haitham Alquorain ¹ Abdul Samad Khan ¹ Faisal Alonaizan ¹ Rashed Alsahafi ³ Michael D Weir ⁴ Hockin H K Xu ⁴

• ¹ Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
• ² King Fahd Military Medical Complex, Dhahran, Saudi Arabia
• ³ Umm al-Qura University, Mecca, Saudi Arabia
• ⁴ University of Maryland, Baltimore, Maryland, United States

Objective: This study aims to incorporate contact-killing quaternary ammonium into two root canal sealers, AH Plus (DentSply Sirona, New York City, NY, USA) and BC (FKG, Le Crêt-du-Locle Switzerland) sealers to improve their antibacterial properties. Methods: Dimethylaminohexadecyl Methacrylates (DMAHDM) were synthesized and incorporated into AH Plus and BC sealers at 5 weight percent (wt.%). The physical properties were assessed via film thickness, flow, contact angle, and solubility. The antibacterial properties were assessed by determining the number of colony-forming units (CFUs) of Enterococcus faecalis and scanning electron microscopy (SEM). Two-way ANOVA and Tukey tests were used to analyze the data. Results: Incorporating DMAHDM at 5 wt.% increased the film thickness and reduced the flow of the AH Plus and BC sealers (P <0.05), but the values were within clinically acceptable limits. Simultaneously, DMAHDM incorporation increased the contact angle of the sealers (P <0.001). DMAHDM incorporation significantly (P <0.001) inhibited the E. faecalis biofilms and resulted in complete eradication. In contrast, the AH Plus and BC control sealers hadapproximately 10 5 and 10 4 CFUs of bacteria, respectively. The SEM images revealed no E. faecalis colonies over the AH Plus sealers containing 5 wt.% DMAHDM, while the AH Plus control sealers were covered with a thick layer of biofilms. Conclusions: The results of this study suggest that DMAHDM, as a contact-killing agent, could be used as an approach to prevent endodontic reinfections. Clinical Relevance: Integrating DMAHDM into commercial sealers may enhance their antibacterial properties. These findings indicate a need for further investigation using more clinically relevant models to validate this approach.