IInclusion criteria:  Patient with skeletal malocclusion, class II or class III that is indicated for bilateral sagittal split osteotomy. Adults >18 years. Systemically healthy.  Exclusion criteria:  Patients not indicated for orthognathic surgery. Severe systemic disease. Have a medical condition associated with systemic neuropathy (e.g. diabetes) Patients whom cannot tolerate follow up intervals. (affect accuracy of study results) Are unwilling to sign informed consent.