Inclusion Criteria:  Patient, women or men over 18 years old Moderate obstructive sleep apnea syndrome (Hypopnea apnea index between 15 and 30) without any serious sign Simple Ronchopathy Indication of video-fibroscopy of upper airways Affiliated subject or beneficiary of a social security scheme Patient having signed the free and informed consent  Exclusion Criteria:  Psychiatric disorders that can be decompensated by hypnosis (bipolarity, schizophrenia, ...) Smoking less than 10 cigarettes per day Alcoholism, chronic or serious disabling pathology Medical history of cancer of upper airways, radiotherapy Pregnancy Recent supper airway infection, rhinosinusitis Active allergy Non-obstructive sleep apnea syndrome severe non-obstructive sleep apnea syndrome (Hypopnea apnea index> 30) Dental contraindication to mandibular advancement device Intolerance or allergy to local anesthesia with Xylocaine spray 5% known Refusal to participate in the study Protected patients: adults under guardianship, curatorship or other legal protection, deprived of liberty by judicial or administrative decision Pregnant, breastfeeding or parturient woman Hospitalized without consent