The degree of stress expressiveness in surgical stomatological patients depends on the adaptation reserve of their organisms. Adaptation to stress in every person is individual. It was found that the most sensitive indicator (marker) of the level of reactivity of an organism in stress is a nociceptive reaction that has the functional stability of neurophysical and neurochemical mechanisms of formation.The aim of the study – to make a screening of the adaptational potential in stomatological patients with different individually-psychological peculiarities under condition of pain stress.Materials and Methods. The objects of clinical observation were 95 surgical stomatological patients. Their individual psychological characteristics were assessed by special questionnaire (S. Novikova, 2006) allowing defi ning the preference of either sthenic or asthenic manifestations in both emotions and behavior of the patients. Neurofunctional research was done by electromyography M-TEST. Stress in patients was induced by electrical stimulation of mental nerve till the appearance of pain reaction that was measured by method of exteroceptive suppression of arbitrary activity of masticatory muscles. It was determined: the threshold of pain, its range and tolerance to pain. According to the results of algometry all the patients were classifi ed into 4 pain perception types. During the operation of the pain factor, a change in the tone of the peripheral vessels was studied by using the index of perfusion (PI), which is according to the literature data recommended for dynamic monitoring of the infl uence of the sympathetic nervous system on hemodynamics. Adaptational vegetative cardiovascular reactions to stress were assessed by the Baievskyi index of functional changes (IFC)=0.011 pulse rate + 0.014 systolic blood pressure + 0.008 diastolic blood pressure +0.014 age + 0.009 body weight – 0.009 growth – 0.27.Results and Discussion. 26 patients with asthenic psychotype in which the threshold of pain and pain tolerance were not high belong to the pain perception type 1. In these patients adaptation of the autonomic nervous system to stress were unsatisfactory (functional changes index (IFC)=(3.35±0.49) points). In patients with the pain perception type 2 threshold of pain sensitivity was similar to those of the type 1, but the range proved to be much longer because of the high threshold of pain tolerance. In this group we noticed functional manifestations of stress-induced analgesia accompanied by exertion of adaptation mechanisms – IFC=(2.86±0.14) points. Such pain perception type was diagnosed in 35 patients with a great prevalence of sthenic features. High pain thresholds were diagnosed in patients with pain perception type 3 and 4, however, owing to the insuffi cient activity of endogenous antinociceptive system in the group 3 the range of pain sensitivity was short. Such pain perception type was found in 15 patients. They manifested both sthenic and asthenic features during psychological testing, Baievskyi stress index (IFC – (3.48±1.12) points) showed unsatisfactory adaptation of cardiovascularsystem to stress in these patients. High indicators of antinociceptive system activity were found in patients with pain perception type 4 including personalities having considerable sthenic characteristics. They showed to have tolerable adaptation of cardiovascular system to stress (IFC – (2.35±0.89) points).Conclusions. The results of clinical observations suggest that the adaptive capacity of patients with stressful (pain) effects depends on their individual psychological characteristics, the level of activation of antistress (antinociceptive) mechanisms, the state of the autonomic nervous system, which are components of the general non-specifi c reactivity of the organism. Patients with increased pain sensitivity are characterized by low resistance to stress, lability of the autonomic nervous system, low level of adaptive capacity. High resistance to stress is characteristic for subjects with stenotic psycho-emotional type, which have high thresholds for pain sensitivity. Adaptation capabilities of the body of patients with stress should be taken into account when they are medically prepared for surgical intervention.