BACKGROUND:Clinical use of mineral trioxide aggregate (MTA) is often associated with several challenges, including a prolonged setting time, poor handling characteristics and compromised physical properties in the presence of tissue fluids. Mineral trioxide aggregate, when used as a perforation repair or root-end filling material, needs adequate strength to withstand the forces acting on it. Recently, several researchers have attempted to overcome these challenges through the use of various additives. OBJECTIVES:To evaluate the physical and antimicrobial properties of MTA reinforced with gold nanoparticles (AuNPs). MATERIAL AND METHODS:Sixteen customized putty molds (6 mm in height x 4 mm in diameter) were filled with the materials assigned to 2 groups: control group, MTA (n = 8); and experimental group, MTA + AuNPs (n = 8). Compressive strength (CS) was evaluated using a universal testing machine, while setting time was assessed using a flat-ended indenter. The antimicrobial properties of MTA and MTA + AuNPs were evaluated using the agar diffusion method against Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans. The data was statistically analyzed using an unpaired t-test. RESULTS:Compressive strength was significantly higher in the MTA + AuNPs group (115.75 ±2.22 MPa) than in the MTA group (55.00 ±5.35 MPa) (p < 0.001). The MTA + AuNPs group also demonstrated a significantly shorter setting time than the MTA group (48.05 min vs. 165.00 min, respectively). The unpaired t-test revealed a significantly greater antimicrobial activity against all tested microorganisms in the MTA + AuNPs group than in the MTA group (P. aeruginosa > E. coli > S. aureus > E. faecalis > C. albicans). CONCLUSIONS:Incorporation of AuNPs into MTA enhanced CS, shortened setting time and increased antimicrobial activity against the tested microorganisms.
A complex cavity is so named because it results from damage to the enamel-dentin complex, and such cavities can cause patients considerable difficulties in daily life. The reconstruction of damaged areas with synthetic restorative materials requires careful consideration of the unique functional properties of natural enamel and dentin, whose inherent characteristics remain superior to those of any synthetic restorative material currently available. The objective of this article was to organize the available information on indirect adhesive restorations for complex cavities, with particular emphasis on the factors and techniques that require consideration during clinical procedures.An electronic search was performed in MEDLINE/PubMed, the Web of Science and Google Scholar. The articles included in this study comprised randomized controlled trials (RCTs), clinical trials, clinical reports, reviews, and laboratory studies.The amount of the remaining natural tooth structure directly affects the longevity of the restored tooth. The remarkable properties of natural enamel and dentin have long been recognized, and bondable restorative materials have therefore been continuously developed with the aim of preserving these natural tissues and reinforcing the remaining tooth structure through effective adhesion. Even when a large portion of the tooth structure has been destroyed, conservative treatment can often still be performed, allowing the benefits of these advanced techniques to be achieved. All aspects of the procedure need to be considered, including material selection, cavity design and preparation, cavity and restoration surface preparation, and the cementation procedure. Additional techniques, including immediate dentin sealing (IDS) and the controversial deep margin elevation technique, are also addressed in this article.
