Characterization of polymethylmethacrylate microspheres loaded with silver and doxycycline for dental materials applications

Exploring the effectiveness of doxycycline in restorative dentistry: a systematic review of in vitro studies

This systematic review evaluated the efficacy of doxycycline in MMP inhibition, its antibacterial action, and other properties relevant to dental materials testing. The study protocol was registered at the Open Science Framework ( https://doi.org/10.17605/OSF.IO/ZVK2T ). Reporting was based on PRISMA statement. The search was carried out in the databases: PubMed, Scopus, Web of Science, Embase, Lilacs, and Google Scholar. Articles were restricted to Portuguese, English, and Spanish, with no date limit. In vitro studies were selected based on the following outcomes: DOX antibacterial and anti-metalloproteinase activity and its influence in physico-chemical properties. Two researchers independently selected the articles and collected the data. Of 1507 documents, 82 were fully evaluated and 21 were included. Different forms of doxycycline incorporation were found, both as free form and incorporated into carrier agents. The drug was tested as primers, incorporated in adhesive or glass ionomer cement. No studies were found that evaluated its incorporation in resin composite or resin cement. The results confirmed the therapeutic properties of the medication, with more significant results when incorporated in an adhesive. However, although promising, the use of this substance requires standardization in application methods and adopted concentrations, allowing for more direct comparisons between studies. Furthermore, long-term studies are interesting to conduct, ensuring biocompatibility and complete understanding of long-term effects on dental materials.

Exploring the Physicochemical, Mechanical, and Photocatalytic Antibacterial Properties of a Methacrylate-Based Dental Material Loaded with ZnO Nanoparticles

While resin-based materials meet the many requirements of a restorative material, they lack adequate, long-lasting antimicrobial power. This study investigated a zinc oxide nanoparticle (ZnO NP)-loaded resin-blend (RB) toward a new antimicrobial photodynamic therapy (aPDT)-based approach for managing dental caries. The results confirmed that up to 20 wt% ZnO NPs could be added without compromising the degree of conversion (DC) of the original blend. The DC achieved for the 20 wt% ZnO NP blend has been the highest reported. The effects on flexural strength (FS), shear bond strength to dentin (SBS), water sorption (WS), solubility (SL), and viability of Streptococcus mutans under 1.35 J/cm2 blue light or dark conditions were limited to ≤20 wt% ZnO NP loading. The addition of up to 20 wt% ZnO NPs had a minimal impact on FS or SBS, while a reduction in the bacteria count was observed. The maximum loading resulted in an increase in SL. Furthermore, 28-day aging in 37 °C water increased the FS for all groups, while it sustained the reduction in bacteria count for the 20 wt% resin blends. Overall, the ZnO NP-loaded resin-based restorative material presents significant potential for use in aPDT.