Experimental studies for maxillofacial prosthesis linings

Marginal gaps might appear between maxillofacial prostheses and adjacent soft tissues causing insufficient fit, which a lining might improve.  Here, the bonding strength of lining silicones on basic maxillofacial prosthesis materials was tested under conditions approximating clinical practice. Addition-curing cross-linking silicones were used. Surface treatment was with a scalpel, a miller or untreated as control. Furthermore, different storage media (artificial saliva solution or vegetable oil) were evaluated for all surface states simulating contact with body fluids.  Tensile and tensile shear tests examined the bonding strength. Tensile shear tests revealed lower bonding strengths than tensile tests. After surface conditioning, the bonding strengths with the basic material conditioned by a miller were statistically significant higher. Stored in oil, they were statistically significantly lower. Lining might compensate fitting deficits from impression or manufacturing shortcomings. For maxillofacial prostheses in patients, the contamination effect of dermal fat and saliva/tissue fluid makes lining seem unpromising.