Lang* R, Rosentritt M, Behr M, Handel G, Taubenhansl P.
(Department of Prosthetic Dentistry, University of Regensburg, Germany)
The aim of this study was to examine the bond strength between soft relining materials and a denture base PMMA material (Paladon 65, Kulzer, G). 4 materials (Mollosil plus, Detax, G; Mucopren soft, Kettenbach, G; Sofrelining material, Tokuyama, J; Ufi Gel C, Voco, G), were used to fabricate 20 tensile test specimens by connecting two rods of PMMA (bonding area: 100 mm2) by means of an intermediate relining layer (thickness 5 mm). Tensile tests (ISO 1562) were performed after storage in distilled water (24hrs, control) (Zwick 1446, v = 60 mm/min). Afterwards the soft relining material was removed and the PMMA surface was reduced for i) 0,1 mm and ii) 1 mm. All samples were divided further into two groups (treatment of PMMA surface with or without monomer) and connected again with Mucopren soft (Kettenbach, G). Tensile test was repeated. Statistics: Mann-Whitney U-Test (P = 0.05).
Replacing the relining material showed higher bonding strength after a minimal PMMA reduction of 0.1mm. Reducing the PMMA surface by 1.0mm, it is recommended to apply additional monomer before application of the new soft relining material.