Facial Nerve Palsy Associated With Orthognathic Surgery

Abstract

45% of patients did not come back for chemodenervation. Treatment cost can be a reason for the high dropout rate (Fig. 1).Other treatment options for unilateral lower lip palsy include selective neurectomy of the healthy contralateral side. Another reconstructive option is reconstruction of the lower lip depressor activity with digastric muscle transfer.Patients with CULLP have high level of concern regarding their mouth symmetry during speech and smiling. Chemodenervation treatment resulted with higher patient satisfaction with speech in comparison to smiling. One possible reason can be the anatomy of the smile as explained by Rubin et al in 1974. 10 There are there 3 types of smile, namely ''Mona Lisa,'' canine and full denture smile. The only smile affected by lower lip palsy is the full denture smile, therefore it can be speculated patients that have the other smile patterns are not affected as much. Whereas unilateral lower lip palsy almost always causes serious asymmetry during speech, especially while pronouncing sounds that incorporate i and e.Although this study was carried out in CULLP patients only, results are also applicable to other DLI related asymmetries. Contralateral DLI chemodenervation is also a very valid option for patients with acquired unilateral lower lip palsy such as Bell palsy, iatrogenic marginal mandibular palsy. CONCLUSIONMost CULLP patients are concerned regarding their asymmetric appearance while smiling or speaking. Chemodenervation of the contralateral DLI muscle reduces concern levels and has high patient satisfaction. Chemodenervation of the contralateral healthy DLI muscle is a valid, practical treatment option.

Facial palsy after orthognathic surgery: Incidence, causative mechanism, management, and outcome

“…The mandibular setback was not likely the solitary causative factor. Other reported reasons included thermal damage by intraoperative electrocoagulation or postoperative ice packing, 7,35 postoperative edema or hematoma at the perimandibular region, 34,36 or injection of vasoconstrictor agents surrounding the ramus causing nerve ischemia. 37 Bell palsy could occur after the orthognathic surgery, as a coincidental viral infection.…”

“…41 As adequate functional recovery of the facial nerve was expected in most cases, expectant observation with conservative management, including physical therapy and the use of steroid, was recommended. 7,48 In our current protocol, we routinely administer dexamethasone intraoperatively to reduce postoperative nausea and vomiting, and also postoperatively to reduce facial swelling depending on the surgeon’s preference. In cases where concomitant viral infection is suspected as a cause of facial palsy, it would be ideal to administer antiviral agents, in addition to early administration of steroids.…”

“…Despite being uncommon, facial nerve injury is one of the most serious complications after orthognathic surgery. 6,7 As cranial nerves run through and in close proximity to the facial skeleton, they are at risk of injury during several steps of orthognathic surgery, and the facial nerve trunk can be injured during the mandibular ramus osteotomy such as sagittal split ramus osteotomy (SSRO). 8,9…”

Cranial Nerve Injuries in Orthognathic Surgery

“…Corticosteroid Complete: 18 cases Sammartino et al, 24 Chrcanovic et al, 12 Bisatto et al, 25 Choi et al, 26 Lanigan et al, 27 Ruiz et al, 28 Shimada et al, 29 Yang et al, 30 Lee et al, 31 Rai et al, 32 Tsai et al, 33 Hsu et al, 34 response in the heart mediated by the vagus nerve. 20,21 This can occur during maxillary separation, chisel insertion into the pterygomaxillary junction, passive maxillary movements, or during channel retractor use in bilateral sagittal split osteotomy.…”

“…Still, facial nerve paralysis is believed to be due to compression and traction of the nerve by mandible bone segments or instruments. [26][27][28][29][30][31][32][33][34]48,49 Moreover, unexpected high condylar neck fractures following mandibular osteotomies have been reported to cause facial nerve paralysis, the same way subcondylar fractures do after trauma. 29 However, given the anatomical distance between the stylomastoid foramen and the pterygomaxillary junction, facial nerve injuries caused solely LeFort I osteotomy are rare.…”