Objective: To check and compare the retenti on of cast posts cemented with three diff erent kinds of cement. Method: Forty fi ve 45 human permanent maxillary...

Introduction Temporomandibular dysfunction (TMD) denotes diseases of the muscles and the mandibular joint, muscular and skeletal diseases, and frequently also parts of systemic diseases of a generalized fibromy-algia, or a form of rheumatoid arthritis. In addition, fear, tension and stressful situations contribute to the overall condition of the masticatory system. (1) Some authors believe that TMD includes pathological diseases primarily affecting the function of muscles and the mandibular muscle, with a possible alteration to the tooth surface. (2) After a cause has crossed the level of individual physiological tolerance of the masticatory system, the system itself starts to respond with certain signs of change. Changes usually happen on the temporomandibular joints (TMJ), supportive tooth structures, and the teeth themselves. (3) The most frequent symptoms of TMD are found in the area of the temporomandibular joint, a sensation of fatigue in the jaw area, a sensation of stiffness of the jaw upon waking up or when opening the mouth, luxation or locking of the mandible when opening the mouth, pain when opening the mouth, and pain in the region of the temporomandibular joint or in the area of the masticatory muscles (cheeks). The most frequent signs of TMD include restricted mandibular movement , lower TMJ function, painful mandibular movement , muscle pain, and pain in the TMJ. (4) TMD causes are complex and multi-factori-al. Numerous factors may lead to TMD. The influence of psychosocial stressors, parafunctions and other psychological and behavioral processes onT-MD pain has been examined in a number of studies. For example, war-related stress has been linked to TMD (5), and stressors as mild as performing mental arithmetic and solving five-letter anagrams can also increase masticatory muscle activity thought to be associated with TMD. (6, 7) Similar relationships between stress and TMD have been reported in children, adolescents and adults. (8, 9, 10) The American Psychiatric Association (11) defines post-traumatic stress disorder (PTSD) as a form of pathological response to stress, in which the patient, through intrusive thoughts and dreams, regularly experiences the trauma suffered, and is consequently placed in a state of permanent increased tension. As a result of increased motor activity and the neu-rotransmitter disruptions which accompany PTSD, particularly with regard to noradrenalin, serotonin, endogenic opiates, and the hypothalamic-pituitary-adrenal axis (12, 13, 14), marked manifestations of symptoms and signs of TMD can be expected. (5)