Filiz A. Keyf, DDS, PhD, A. Ihsan Keyf, MD

Hacettepe University, Ankara 06100, Turkey 'General Practitioner, Ataturk Chest Disease Center, Ankara, Turkey

Methylmethacrytate has been extensively used as a dental prosthetic and as a cranial-bone substitute for years. Methylmethacrylate and formaldehyde which is formed as oxidation products of the residual methylmethacrylate monomer are allergic agents responsible for mucosal injuries. Methylmethacrylate monomer also causes allergic stomatitis and dermatitis. Exposure of lungs and trachea to methylmethacrylate vapor is harmful. Significant pathologic changes as loss of cilia of tracheas and bronchial respiratory epithelism, hyperplasia of peribronchiolar lymphoid follicles, and respiratory capillary hyperemia may result. When used as a cranial-bone substitute, the monomer enters the systemic and pulmonary circulation. Hemorrhagic lesions of the lung parenchyma, acute hypotension leading to cardiac arrest and cardiovascular collapse may occur. Cardiovascular effects following insertion of bone resin cement during orthopedic procedures are widely believed to be only mild and transient, however.