A case of mucopolysaccharidosis type I with coronoid process hyperplasia

Mucopolysaccharidosis is a metabolic disorder causing a range of symptoms.The condition may result from a deficiency of an intracellular glycosaminoglycan-degrading enzyme.There have been reports of distinctive characteristics in the maxillofacial region, including macroglossia, open bite and a higharched palate.We report the case of a patient with mucopolysaccharidosis type I who underwent a bilateral coronoidectomy due to coronoid process hyperplasia, with a positive outcome in terms of extent of mouth opening.A 10-year-old boy was diagnosed with mucopolysaccharidosis type I at the age of 1 year.At the initial examination, the extent of mouth opening was 21 mm, and bilateral coronoid process hyperplasia was suspected based on the clinical findings.Conservative follow-up was continued from a growth and development perspective; however, the symptoms gradually progressed, and surgery was scheduled 11 years later.Preoperatively, a cutting guide was created, and airway obstruction was evaluated at the otolaryngology department.Accordingly, a bilateral coronoidectomy was performed under general anesthesia.Although the surgical field was limited, an osteotomy was performed at the suspected site using the cutting guide.Postoperatively, the mouth opening extent had increased to 45 mm and there were no complications.The patient could maintain an opening of >40 mm after approximately one year.