The authors examined 120 dental technicians, 111 women, 9 men, of mean age 44.8 years, mean duration of exposure 24.9 years. Cold water test, plethysmographic investigation, and EMG (in indicated persons), X-ray, neurological and orthopedic examinations were performed. Combination of exposure to vibration above the limit value, with overload of upper extremities, was proved by hygienic measurement. The most frequent subjective complaints included vertebral complaints (52.5%), paresthesiae in the hand fingers (47.4%) and pain in the joints of upper extremities (elbow 26.6%, shoulder 10.8%, wrist 6.6% and small joints of hand 6.6%). Four workers reported history of white fingers, but the cold water test did not prove it. Deteriorated plethysmographic curve was in 11 cases only. Pathological motor conduction in nervus medianus was found (by EMG investigation) in 13 persons. Carpal tunnel syndrome was acknowledged in 4 individuals as an occupational disease. The results of these investigations show the hazard of dental technicians work and the necessity of improvement of their work conditions.