we inject I-PRF and Hyaluronic Acid inside the human TMJ with internal derangement after arthrocentesis, and follow-up is made to evaluate the effect of this treatment.

This study was made to evaluate the efficacy of injectable Platelet Rich Fibrin (I-PRF) with Hyaluronic Acid (HA) injection after arthrocentesis in treatment of Temporomandibular joint Internal Derangement.

The study was conducted on 30 patients whose ages ranged from 18 to 40 years, presented with impaired jaw function, limited mouth opening, Pain during joint movement and clicking. TMJ internal derangement was verified by preoperative MRI.

Patients with MPDS only, systemic debilitating disease, previous surgery in the TMJ, previous arthrocentesis, previous trauma to the joint were excluded from the study.

Control group: 15 cases were treated by arthrocentesis then injection of 1ml of Hyaluronic acid (HA).

Study group: 15 cases were treated by arthrocentesis then injection of 0.5ml of Hyaluronic acid (HA) and 0.5ml of injectable platelet rich fibrin (I-PRF).

Clinical assessment of pain by VAS, clicking as present or not, maximum mouth opening in millimeters, right and left lateral movements and protrusive movements was done preoperatively and postoperatively at 1,3,6 months.

MRI assessment was done preoperatively and 6 months postoperatively.

Inclusion Criteria:

1. patients aged from 18 to 40 years old.
2. patients diagnosed with internal derangement of TMJ, suffering from limited mandibular movements, joint pain and clicking.
3. Patients who are free from any systemic disease (ASA I).

Exclusion Criteria:

1. Patients who have myofascial pain dysfunction syndrome only.
2. Patients who have previous surgery in TMJ.
3. Patients who have previous arthrocentesis within 1 year.
4. Patients with prosthetic joint replacement.
5. Patients allergic to any components of the injecting solution.
6. Patients who received previous trauma to the joint.