Endotracheal intubation is a procedure performed during general anaesthesia with the use of an endotracheal tube in order to maintain a patent airway. This routinely used procedure is connected with a risk of complications within the region of the masticatory system. Trauma of teeth, their surrounding structures and the soft tissue of the oral cavity is observed in app. 1.38 per 1000 procedures. The main causes of this damage are the surgical skills and experience of the surgeon, the anatomical conditions present and the mode of conducting the procedure. In order to reduce the risk of postoperative complications, patients with a high risk of sustaining an injury during endotracheal intubation should be equipped with elastic mouthguards, which reduces the possibility of damage. The scoring in a scale of endotracheal intubation difficulty should be used for qualification for the use of such mouthguards.