Comparative evaluation of flexural strength of heat-polymerized acrylic resin repaired using metal- and fiber-reinforced autopolymerizing resin: An in vitro study

Objectives: To evaluate the flexural strength of heat-polymerized acrylic resin repaired using autopolymerizing resin alone, metal wire-reinforced autopolymerizing resin, and glass fiber-reinforced autopolymerizing resin, and to compare the reinforced techniques with the conventional repair method. Methods: Standardized acrylic resin specimens were fabricated and divided into three groups. Group 1 specimens were repaired using autopolymerizing acrylic resin alone. Group 2 specimens were reinforced with sandblasted metal wire, and Group 3 specimens were reinforced with woven glass fiber. Flexural strength testing was performed using a universal testing machine at a crosshead speed of 5 mm/min until specimen fracture. The obtained values were statistically analyzed. Results: Mean flexural strength values were 51.34 MPa for Group 1, 69.71 MPa for Group 2, and 59.99 MPa for Group 3. Statistically significant differences were observed among the three groups (p < 0.001). The highest flexural strength was demonstrated by the metal wire-reinforced group, followed by the glass fiber-reinforced group, while the control group exhibited the lowest values. Conclusions: Reinforcement of repaired acrylic resin dentures using metal wire or glass fiber significantly improves flexural strength compared to conventional repair techniques. Sandblasted metal wire reinforcement demonstrated superior mechanical performance among the evaluated methods.