Microleakage study of various soft denture liners by autoradiography: Effect of accelerated aging

Statement of problem. The longevity of soft denture liners is a major clini cal problem. Debonding of the soft liner from the denture base material is one of the factors that influence their longevity: Debonding of the soft li ner can be attributed to microleakage at the interface. Purpose. This study investigated microleakage at the interface of various s oft liners and base materials. Materials and method. Six soft liners were investigated. Forty specimens of each material in disk form ( 10 mm in diameter, thickness of approximately 4 mm) were prepared. Twenty specimens of each material were stored in an a ccelerated weathering tester for 900 hours. For 2 days, all disks were imme rsed in Ca-45 radioisotope solution, then they were embedded in acrylic res in blocks and sectioned longitudinally: Autoradiographic imaging was used t o determine microleakage at the interface of the soft liners and their base s. Results. Significant differences between nonaged materials were found(P<.05 ). The difference between Molloplast B and Mucopren (silanized) was not sig nificant (P>.05). Differences among aged materials were significant (P<.05) . Differences between Mucopren (nonsilanized), Mucopren (silanized), and Uf igel P-Tokuyama were not significant (P>.05). Significantly decreased micro leakage characteristics were determined for Molloplast B, Mucopren (nonsila nized) and Ufigel P liners after aging. Conclusion. Microleakage of Mucopren and Molloplast B lining materials was the lowest. However, the microleakage of Flexor and Simpa was the highest. The aging process did not significantly affect the microleakage characteris tics of the Simpa, Flexor, Mucopren (silanized), or Tokuyama. materials, Mo lloplast B, Mucopren (nonsilanized), and Ufigel P materials should signific antly decrease microleakage properties after aging.