The goal of this clinical trial is to learn if arthrocentesis works as well as botulinum toxin (Botox) injection to treat pain and jaw dysfunction in adults with temporomandibular joint (TMJ) disorders.

The main questions it aims to answer are:

• Does arthrocentesis reduce pain more, less, or the same as Botox injection?
• Does arthrocentesis improve jaw opening and function more, less, or the same as Botox injection?
• What side effects do participants have with each treatment?

Researchers will compare arthrocentesis to Botox injection to see which treatment works better for reducing pain and improving jaw movement in patients with TMJ disorders.

Participants will:

• Be randomly assigned to receive either arthrocentesis (a joint-washing procedure) or a Botox injection into the jaw muscles
• Visit the clinic at 1, 3, and 6 months after treatment for checkups and assessments - Rate their pain and have their jaw movement measured at each visit
• Complete short questionnaires about their jaw function and quality of life