The endotracheal intubation is a procedure of placement the tube directly into the trachea to insure the airway. It is used in everyday`s hospital practice during intervention under general anesthesia, recovering on Intesive Care Unit or in emergency providing for apnoic patients. It is performed by a laryngoscope with straight or curved blades, endotracheal tube, stilets- conductor for the tube and the other accessories for fixation of a positioned tube. The intubation can be nasotracheal or orotracheal. The nasotracheal intubation is performed via nasal cavity till oropharynx, and then with Magill`s clamps and the laryngoscope into the trachea. It is prefered in present of the C spine trauma, serious injuries of oral cavity and patients with trismus. It is contraindicated during emergency in apnoic patients, and when a severe mid-facial fracture and basilar fracture exist, too. The orotracheal intubation is performed via oral cavity by laryngoscope. The tube is with laryngoscope placed, through the larynx and vocal cords to the bifurcation trachea. As the other procedure ETI can cause complications which depend on knowleage and expiriance of the physician and also on the condition of the patient. Some of them can be life threatening causing hypoxic brain damage or death, like for example: faild intubation or oesophageal or bronchial intubation. Some of them are not letal, but can prolonge recovering like teeth trauma or oral tissue trauma. To prevent teeth trauma it is necessery before surgical procedure, and intubation itself, assess at least by visual inspection the condition of oral cavity. The high risk patients (patients with periodontal disease, limited mouth opening or malocclusion) require detail examination.