Inclusion Criteria:  Age ≥ 18 years; American Society of Anesthesiologists physical status I~II; Scheduled to undergo elective oral and maxillofacial surgery requires nasal intubation; The expected operation time < 3 hours; Extubation in operation room and do not scheduled to preventive tracheotomy; Patients who were able to breathe clearly and equally through both nostrils.  Exclusion Criteria:  Patients had history of difficult intubation or presented with an anticipated difficult airway; Patients requiring nasogastric tube insertion; Presence of contraindications of nasal intubation; Due to surgical requirement, intubation must be completed through one nostril; Presence of severe nasal obstruction,deformities of the nasal cavity, or other serious nasal diseases; History of severe epistaxis or epistaxis within a month; Previous history of nasal and/or laryngeal surgery; Previous experience with nasal intubation; History of schizophrenia, Parkinson's disease or profound dementia, or language barrier; Participate in other clinical studies; Refusal to sign informed consent.