Flexural strength of denture bases repaired with metal wires Comparison among different amounts of metal wires / 中国组织工程研究

ABSTRACT

BACKGROUND: Poly methyl methyacrylate (PMMA) has been widely used as a denture base material in dental field for a long time. However, the fracture of acrylic resin dentures is an unresolved problem in prosthodontics. Therefore, how to improve the flexural strength of repaired denture seems to be extremely important. OBJECTIVE: To study the effect of embedding different amounts of metal wires on the flexural strength of repaired denture bases. METHODS: Twenty-five rectangular specimens (50 mm× 30 mm × 2.5 mm) were fabricated using heat-cured acrylic resins and randomly and evenly divided into five groups A, B, C, D, and E. All specimens were fractured through the use of universal testing machine, and the flexural strengths were tested. Following preparation of fracture surfaces, one to four metal wires were separately embedded in the groups B, C, D, and E. No metal wires were embedded in the group A. All fractured specimens were repaired using self-curing resins. The flexural strengths were measured again using the same testing machine, and the percentages of strength recovery were calculated. RESULTS AND CONCLUSION: After repair, the flexural strengths were obviously reduced (P < 0.01). Compared to group A, the percentages of strength recovery were significantly increased in groups C, D, and E (P < 0.05). There was no significant difference in the percentage of strength recovery among groups C, D, and E (P > 0.05). These results indicate that embedding two to four metal wires can improve the flexural strength of denture bases.