This is a 38 year old male patient, who reports limitation of oral opening which he noticed started at the age of 18 and has been progressing. Totally asymptomatic, he already has difficulty feeding. In addition, he suffers from various intraoral carious foci that the dentists he has visited have declared impossible to treat due to the reduced oral opening. The patient refers to multiple treatments with different specialists trying to improve this oral opening, with physical therapies and jaw exercises, which have been totally ineffective.
At the time of the first examination, the patient had a maximum oral opening of 16 mm, which did not change when forced, and the patient had a panoramic X-ray and computerised tomography in which an evident elongation of the coronoid processes above the level of the zygomatic arch was observed. Once diagnosed as HPC, it was decided to perform the bilateral coronoidectomy by means of an intraoral approach, with a maximum oral opening of 40 mm during the trans-operative period.

Three days after surgery, physical therapy was started with oral opening exercises and support with tongue depressors, with good progress during the first week (maximum oral opening of 21 mm). Subsequently, his oral opening became critical (6 mm of maximum oral opening). It was decided to use functional orthopaedic appliances, with the use of the Spring-Bite, with an interval of 10 minutes, 4 to 5 times a day, obtaining an oral opening of 30 mm 30 days after its use. The use of the appliance was continued for 6 months.