Sung-Hun Kim1, David C Watts. 1. Department of Prosthetic Dentistry, Ewha University, Seoul, Republic of Korea. ksh1250@ewha.ac.kr
Abstract
STATEMENT OF PROBLEM: The fracture of acrylic maxillary complete dentures occurs frequently during service through heavy occlusal force or accidental damage. PURPOSE: The purposes of this study were to measure the impact strength of maxillary complete dentures fabricated with high-impact acrylic resin and to evaluate the effect of woven E-glass fiber-reinforcement on the impact strength of the complete dentures. MATERIAL AND METHODS: Preimpregnated woven E-glass fibers (Stick Net) were used to reinforce 10 complete denture bases fabricated with a heat-polymerized high-impact acrylic resin (Lucitone 199). Ten unreinforced complete dentures served as a control group. All specimens were stored in water at 37 degrees C for 2 months before testing. The impact strengths (J) of the dentures were measured with a falling-weight impact test. The impact strengths of both groups were compared by a repeated measures analysis of variance (alpha=.05). The Weibull distribution was also applied to calculate the cumulative fracture probability as a function of impact strength. RESULTS: The mean impact strength of the control dentures was 90.0+/-38.1 J at crack initiation, and 95.9+/-37.7 J at complete fracture, whereas the impact strength of reinforced dentures was 201.7+/-77.9 J and 277.9+/-102.5 J, respectively. Statistical analysis showed that impact strength of the high-impact acrylic complete denture was significantly increased by the addition of woven E-glass fiber (P<.0001). CONCLUSION: The impact strengths of maxillary complete dentures fabricated with high-impact acrylic resin increased by a factor greater than 2 when reinforced with woven E-glass fiber.
STATEMENT OF PROBLEM: The fracture of acrylic maxillary complete dentures occurs frequently during service through heavy occlusal force or accidental damage. PURPOSE: The purposes of this study were to measure the impact strength of maxillary complete dentures fabricated with high-impact acrylic resin and to evaluate the effect of woven E-glass fiber-reinforcement on the impact strength of the complete dentures. MATERIAL AND METHODS: Preimpregnated woven E-glass fibers (Stick Net) were used to reinforce 10 complete denture bases fabricated with a heat-polymerized high-impact acrylic resin (Lucitone 199). Ten unreinforced complete dentures served as a control group. All specimens were stored in water at 37 degrees C for 2 months before testing. The impact strengths (J) of the dentures were measured with a falling-weight impact test. The impact strengths of both groups were compared by a repeated measures analysis of variance (alpha=.05). The Weibull distribution was also applied to calculate the cumulative fracture probability as a function of impact strength. RESULTS: The mean impact strength of the control dentures was 90.0+/-38.1 J at crack initiation, and 95.9+/-37.7 J at complete fracture, whereas the impact strength of reinforced dentures was 201.7+/-77.9 J and 277.9+/-102.5 J, respectively. Statistical analysis showed that impact strength of the high-impact acrylic complete denture was significantly increased by the addition of woven E-glass fiber (P<.0001). CONCLUSION: The impact strengths of maxillary complete dentures fabricated with high-impact acrylic resin increased by a factor greater than 2 when reinforced with woven E-glass fiber.