ANTIMICROBIAL ACTION OF A MODIFIED UNIVERSAL ADHESIVE: AN IN VITRO STUDY.

Background: Resin composites and dental adhesives are widely used to restore carious teeth. A relatively new category of the dental adhesives, the universal adhesives (UAs) is considered user friendly because of its simplicity to use and compatibility with any adhesive strategy. However, the adhesive interface created by these adhesives is highly susceptible to cracking after polymerization which in turn facilitates the initiation of secondary caries.

Objectives: The present study was set to evaluate the antimicrobial action of All Bond Universal Adhesive after modifying it with chitosan capped cerium nanoparticles (C-CeNPs) against S. muatns and L. acidophilus.

Materials and methods: A colloidal suspension of C-CeNPs was synthesized, characterized, and incorporated into the universal adhesive. Two groups of adhesives were used: G I without C-CeNPs and G II with 3% by weight of C-CeNPs. The antimicrobial action of G I and G II was evaluated by agar diffusion test (ADT) and direct contact test (DCT) at 1, 7, and 14-day time intervals.

Results: For ADT, G II resulted in larger inhibition zones against both microbial strains than G I. The inhibition zones for G I and G II where larger against S. mutans than L. acidophilus. For the DCT, less colony forming units (CFU) of both microbial strains were formed in regard to G II than G I. The number of CFU of both microbial strains increased in line with the time intervals.

Conclusions: Incorporating C-CeNPs into the universal adhesive increased its antimicrobial action against S. muatns and L. acidophilus microbial strains.