Abstract
Acrylic resin materials are used for making dentures, artificial teeth, veneers, crowns, and temporary crowns, etc. The surface structure of acrylic resins as well as composite resin and ceramic are a favourable environment to the bacterial plaque development. Researches from domain lead to more qualitative acrylic resin and polymers: diacrylic composite resins, epoxide resins, etc. Diacrylic composite resins have superior mechanical and aesthetic properties but are inferior to ceramics. The prosthetic restorations and the presence of different materials in the oral cavity represent a proper environment for the development of microbial flora. The oral cavity health depends on correct prosthetic treatments and a balanced microbial flora that can be controlled with bacteriostatic substances, oral hygiene and correct prosthetic restorations. Bacteriostatic effect of silver nano-particles over plastic dental materials may influence and contribute to the activity of bacterial micro-flora and may influence the evolution of periodontal disease and gingivitis by destroying the dental plaque. Key words: acrylic resin, diacrylic composite resins, crowns, silver nano-particles