title: The evaluation of surgical factors related to recovery period of upper lip hypoaesthesia after Le Fort I osteotomy.
abstract: OBJECTIVE
  It is unclear whether surgical factors can affect the upper lip sensitivity. The aim of this study was to assess the factors that can affect the recovery period of hypoaesthesia of the upper lip after Le Fort I osteotomy, using trigeminal somatosensory evoked potential (TSEP) objectively.
  
  
  METHODS
  Twenty-nine patients with mandibular prognathism underwent Le Fort I osteotomy with and without artificial pterygoid plate fracture. Trigeminal nerve hypoaesthesia at the region of the upper lip was assessed bilaterally by the TSEP method. The distance between the infraorbital foramen and the osteotomy line (IO) or the nearest plate/screw position (IP) was measured on three-dimensional computed tomography (CT). The relationship between the recovery period in upper lip hypoaesthesia and surgical factors (these distances, movement amount, pterygoid plate fracture) were analysed statistically.
  
  
  RESULTS
  The recovery period in upper lip hypoaesthesia did not significantly correlate with IO, IP and movement amount. There was no significant difference between pterygoid plate fracture group and non-fracture group.
  
  
  CONCLUSIONS
  Temporary hypoaesthesia of upper lip after Le Fort I osteotomy could not be avoided, however, osteotomy line, plate/screw position and pterygoid plate fracture in Le Fort I osteotomy did not affect the recovery period of upper lip hypoaesthesia with TSEP.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Graduate School of Medicine, Kanazawa University, 13-1 Takaramachi, Kanazawa 920-8641, Japan. kueki@med.kanazawa-u.ac.jp
authors.forename: Koichiro
authors.initials: K
authors.lastname: Ueki
authors.forename: Yukari
authors.initials: Y
authors.lastname: Hashiba
authors.forename: Kohei
authors.initials: K
authors.lastname: Marukawa
authors.forename: Kiyomasa
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Shamiul
authors.initials: S
authors.lastname: Alam
authors.forename: Etsuhide
authors.initials: E
authors.lastname: Yamamoto
mesh_terms: D000293:Adolescent; D000328:Adult; D001860:Bone Plates; D001863:Bone Screws; D005073:Evoked Potentials, Somatosensory / Q000502:physiology; D005146:Facial Asymmetry / Q000601:surgery; D005260:Female; D006801:Humans; D006987:Hypesthesia / Q000209:etiology*; D021621:Imaging, Three-Dimensional / Q000379:methods; D019344:Lactic Acid; D008046:Lip / Q000294:innervation*; D008297:Male; D009915:Orbit / Q000601:surgery; D010027:Osteotomy / Q000295:instrumentation; D019340:Osteotomy, Le Fort / Q000295:instrumentation / Q000379:methods; D011091:Polyesters; D011108:Polymers; D011183:Postoperative Complications; D011378:Prognathism / Q000601:surgery; D011930:Reaction Time / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology*; D012887:Skull Fractures / Q000209:etiology; D013100:Sphenoid Bone / Q000293:injuries; D014025:Titanium; D014057:Tomography, X-Ray Computed / Q000379:methods; D014276:Trigeminal Nerve / Q000503:physiopathology; D055815:Young Adult
chemical_list: D011091:Polyesters; D011108:Polymers; D019344:Lactic Acid; C033616:poly(lactide); D014025:Titanium