Left-Sided Mandibular Condylar-Ramus Deficiency Within the Craniofacial Microsomia Spectrum in a 10-Year-Old Patient: A Case Report.

We present the case of a 10-year-old female patient with a progressive limitation of mouth opening since early childhood, worsening at eight years of age, with difficulty tolerating solid food and impaired mastication. Physical examination revealed facial asymmetry predominantly affecting the lower third of the face, with a maximal interincisal opening of less than 8 mm and mandibular deviation toward the left during mouth opening. Computed tomography with three-dimensional reconstruction demonstrated a marked hypoplasia of the left mandibular condylar-ramus unit, a severe shortening of the ramus, and unilateral mandibular underdevelopment. Based on the clinical and imaging findings, the case was interpreted as left-sided mandibular condylar-ramus deficiency/unilateral mandibular hypoplasia within the craniofacial microsomia spectrum. Surgical management consisted of mandibular reconstruction using an autologous costochondral graft. Due to anticipated airway difficulty, orotracheal intubation was initially achieved with videolaryngoscopy, followed by temporary tracheostomy for intraoperative airway control, which was successfully decannulated seven days after surgery. A preauricular approach was used to access the temporomandibular region, and a costochondral graft harvested from the fifth rib was shaped and fixed to reconstruct the condylar-ramus unit. The patient demonstrated immediate functional improvement, with increased mouth opening observed within 24 hours postoperatively. At 12 months of follow-up, she maintained a maximal mouth opening of 16 mm, without complications and with improved tolerance to oral intake. This case documents immediate and sustained functional improvement after mandibular reconstruction in a pediatric patient with severe unilateral mandibular deficiency.