Stress is a process that activates neuronal, metabolic, and neuroendocrine mechanisms. The individual's response may be determined by variables such as genetic factors, environmental conditions, sex, and age, among others. These responses are critical for survival, and the involvement of the hypothalamic-pituitary-adrenal axis is necessary for adaptation, which through counter-regulatory mechanisms seeks to restore homeostasis. Dentists are aware that there are variations in people's response to treatment, and there are many patients in whom dental treatment generates an important source of stress, which in many cases leads to treatment avoidance behavior.