Which surgery unlocks a locked jaw? a Head-to-Head test

This trial compares two surgical techniques for treating a painful jaw condition called disc displacement without reduction, where the jaw's cushioning disc slips out of place and limits mouth opening. Participants will receive either arthroscopic lysis and lavage, a procedure that rinses the joint and breaks up adhesions, or arthrocentesis, a simpler irrigation, both under general anesthesia. The study will measure improvements in mouth opening, jaw pain, and disability over two years, and also look for factors that predict success. The goal is to determine which method offers better relief for people with this disabling condition.