2 dental technicians, both with chronic hand eczema, reported worsening from the use of 2 products containing methyl methacrylate, employed in manufacturing acrylic prostheses. Patch tests in both patients gave positive reactions to methyl methacrylate, ethylene glycol dimethacrylate and products employed in manufacturing acrylic prostheses (2% and 5% pet.). On the basis of results subsequently obtained from patch tests carried out with pieces of glove interposed between the skin and the allergens (methyl methacrylate and products employed), we advised our patients still to use latex gloves during work. Follow-up after 1 year showed complete regression of the dermatitis in 1 case and considerable improvement in the other.