title: [Isolated paralysis of the ramus marginalis mandibulae nervi facialis: clinical aspects, etiology, diagnosis and therapy. An overview].
abstract: BACKGROUND
  Disorders of lower lip in facial expression are mostly caused by functional impairment of the marginal mandibular branch of the facial nerve. In a typical case, active exposure of the incisors of the mandible is not possible and the lip appears distorted towards the healthy side. The most frequent cause of a lesion of the marginal mandibular branch is iatrogenic injury during operations in the mandibular or parotid region.
  
  
  METHODS
  Functional disorders of the platysma, congenital hypoplasia or aplasia of the lower lip muscles, and defective healing following facial palsy may lead to a similar disorder which, however, must be differentiated from an isolated paralysis of the marginal mandibular branch.
  
  
  METHODS
  In addition to inactivation of the nerve branch on the opposite side, several surgical procedures have been described to achieve not only aesthetic, but also functional rehabilitation of lower lip expression. The present review gives an overview on the causes, clinical appearance, diagnosis, differential diagnosis, and therapy of unilateral isolated paresis of the marginal mandibular branch of the facial nerve.
authors.affiliation: Klinik und Poliklinik für Hals-Nasen-Ohrenkrankheiten, Universität Göttingen.
authors.forename: R
authors.initials: R
authors.lastname: Rödel
authors.forename: R
authors.initials: R
authors.lastname: Laskawi
mesh_terms: D005149:Facial Expression; D005154:Facial Nerve / Q000503:physiopathology; D020220:Facial Nerve Injuries; D005158:Facial Paralysis / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008046:Lip / Q000294:innervation*; D008334:Mandible / Q000294:innervation*; D011183:Postoperative Complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy