A multitude of resins were used in dental procedures for the production of dental prosthesis ever since 1930s, and their success has already been based on physical, chemical, and biological qualities. Initially, denture bases were made of nitrocellulose, vulcanite, venylplastics, phenol formaldehyde, and porcelain. The acrylic resins have been so favorably embraced by the practitioner that by 1946, methyl methacrylate polymers or copolymers were used to make 98% percent of all denture bases. (1)
Initially, the conversion of the monomer to polymer, that is commonly accomplished using a hot water bath or a microwave, is needed for the polymerization of such a resin (2, 3). Interest for the good properties, suitable strength, poor water sorption, poor solubility, in moreover to being free of toxicity, easy repair ability, the ability to reproduce accurately the features and size of pattern, and easiness of plaster molds and processing technique have all contributed to the success of acrylic resin as denture bases (4, 5). Denture breaking is frequently caused by inadequate design, production, and/or material selection. Denture fails beyond the mouth as a consequence of the prosthesis being ejected from the mouth during coughing or falling the denture. Excessive gripping pressure within the mouth can potentially cause fractures (6, 7). Cracks with in midline of maxillary full dentures seem to be more frequent (6, 8). Moreover, instead of in the middle of the restoration, denture failures frequently develop near the junction of past and present materials (9).
The goal of prosthesis repair is to restore the natural form and strength of the denture for the least amount of money and time feasible. A number of treatments and materials were used to repair frayed prosthesis. To repair damaged acrylic resin prostheses, auto polymerized acrylic resin, heat curing acrylic resin, and, most recently, visible light-curing acrylic resin are utilized (10, 11) The rate of acrylic resin prosthesis failure because of broken has been shown to be accepted (12).
Acrylic plastic has long been the most popular and well-liked of all denture base materials, accounting for over 95% of all plastics used in prosthodontics (13, 14). Metallic and non-metallic materials are the two types of materials utilized as denture foundations (15, 16). Nothing has yet been found that can match the appearance of the soft tissues of the mouth as well as acrylic resin. It is not only visually beautiful when first placed in the mouth, but it also retains its beauty over time provided the patient follows a simple cleaning and hygienic care regimen (17). Such dental resins are frequently given in two parts: a liquid monomer called methyl methacrylate (MMA) and a powder called polymer (18).
The purpose of this research is to test the fatigue bond strength and impact bond strength of light-cured acrylic resins in denture repair using various chemical solvents such as acetone, monomer, and thinner (in vitro).