Dentistry uses a variety of different polymer materials. Dental polymer materials are based on methacrylate, its polymer, and polyelectrolytes. The setting of restorative materials and adhesives is initiated chemically by mixing two components or by light. In both cases, polymerisation is incomplete and monomers, not reacted, release. Studies have documented that monomers may cause a wide range of adverse health effects such as irritation to skin, eyes or mucous membranes, allergic dermatitis, asthma, parenthesise in the fingers, and disturbances from central nervous system such as; headache, pain in the extremities, nausea, loss of appetite, fatigue, sleep disturbances, irritability, loss of memory and changes in blood parameters. Dental personnel are occupationally exposed when handling the non reacted monomers. The use of gloves do not give enough protection as monomers, released from the material, easily penetrate all gloves used in dentistry. Face masks do not prevent inhalation of monomers. Ordinary glasses do not protect the eyes against vapor from monomers. The result from this study demonstrate the need for the development of ergonomic procedures and practices for safe handling of such materials in dental clinics.