The sensory innervation of the face depends on the trigeminal (fifth cranial) which is divided into three branches, the mandibular nerve (V3) having motor fibers to the temporal and masseter muscle. The regional anesthesia of the face has grown in recent years for performing certain actions under light general anesthesia or sedation. The mandibular block is a simple and reliable technique but little used. Yet it reduces postoperative pain sagittal osteotomy of the mandibular branch by reducing consumption of opioids and in the oropharynx cancer surgery. Made with ropivacaine, known for its vasoconstrictive action, it also improves the visibility of the operative field during mandibular osteotomies reducing bleeding. Despite a real clinical benefit (ease of implementation, latency and duration of action of the local anesthetic), the V3 block ropivacaine is not evaluated in the maxillofacial surgery.

Inclusion Criteria:

• adult patients and patients from 15 to 18 years old
• with mandibular trauma or orthognathic surgery
• Affiliated to a national insurance scheme
• to have signed the informed consent of this study
• Physical status score 1-3

Exclusion Criteria:

• allergy to local anesthetics
• severe coagulopathy
• hypovolemic patient
• Protected minor or major patients or in the incapacity to give his consent according to the article L1121-8 of the Code of the Health Public.
• Pregnant or breast-feeding women according to the article L1121-5 of the Code of the Health Public.
• Vulnerable People.