Six-month Efficacy of Ultrasound-guided Platelet-rich Plasma Injection for Temporomandibular Disorders

Objectives:

Temporomandibular disorder (TMD) involves the temporomandibular joint (TMJ) and surrounding structure, causing problems including myofascial pain and joint degeneration. TMD is mostly seen in the age group of 18 to 44. TMD treatment includes conservative (non-surgical) and surgical treatment. Surgical TMD treatment has a decent success rate but requires general anesthesia, hospital stay and surgical incision. There are also some risks of facial nerve and vascular damage, infection, puncture to middle cranial fossa. Conservative treatments include medication , physical therapy, use of occlusal splint, hyaluronic acid (HA) or Botulinum toxin injection and concentrated glucose solution. However, those managements lack the evidence from large placebo-controlled clinical trials. Therefore, the development of novel non-surgical treatment is important and of great potential. The ultrasound guidance provides visualization of the lesion site, allowing the operator to provide injection precisely and avoid damage on adjacent tissue, nerves and vessels. it is not only convenient and economic, but also associated with significantly less radiation exposure than conventional techniques such as computer tomography or fluoroscopy. Using ultrasound guidance in injective TMD treatment can increase successful rate and prevent unnecessary side effects. While current available evidences suggest the promising effect of platelet-rich plasma (PRP) injection therapy in treating TMD, publication of study with strict design is still lacking. Therefore, this study is a randomized, controlled and double-blind design, which aimed to access the efficacy of ultrasound-guided PRP injection therapy of TMD, with normal saline used as control. Looking forward to establish TMD clinical treatment guideline in the future.

Methods:

The out-patients with unilateral or bilateral TMD、joint mobility dysfunction or joint noise from this hospital were enrolled. They were randomized via computer into 2 groups (PRP group and normal saline group). There are 30 patients in each group. The PRP group received 1cc PRP injection in the superior temporomandibular disk joint space by ultrasound guidance. The normal saline group received the same procedure as PRP group with 1 cc normal saline injection. Both group received the same protocol of physical therapy (manual therapy, stretching exercise, posture training with 30 minutes per session and 2 sessions per weeks) for 12 weeks. Those physical therapies were under the guidance of one therapist who didn't know the patient's allocation.

The investigator and subjects did not know the group assignment. Evaluations were performed at time points prior to injection and 2 weeks, 1st, 3rd , and 6th months post injection by one doctor (who didn't know about the group assignment). Evaluations include Visual Analogue Scale (VAS) of the degree of pain, masticatory efficiency, perceived joint noise and measure of maximal interincisal opening, painless oral opening, mandibular lateral movement and protrusion movement. The investigator also evaluated symptoms or signs of side effects and complications.