Evaluation of the Accuracy of Sonograph Guided Intra-Temporomandibular PRP Injection and its Ability to Relieve Symptoms: Randomized Controlled Single-Blinded Clinical Study.

Objective: To compare the ultrasound-guided method with the traditional method for injection into the upper joint space of the TMJ involving mouth maximum opening changes, joint pain changes, joint sounds, and correct placement of the injection material into the upper joint space. Methods: 24 patients who complained of TMD symptoms associated with internal derangements were included in the study and got an intra-articular injection of platelet-rich plasma with iohexol contrast agent. Patients were randomly divided into two groups: 12 patients were injected by the ultrasound-guided method in the guided group, and 12 patients were injected by the conventional method in the traditional group. The correctness of the mixture placement into the upper joint space was assessed by performing a CBCT following the injection of the mixture and showing the images to two blinded radiologists. Mouth maximum opening, joint pain, and joint sounds were assessed by a blinded physician, and follow-up after 1 week, 1 month, and 3 months. Results: The guided method showed correct placement of the injection mixture in 91.7%, while the traditional method showed correct placement of the mixture in 66.7%. There were no significant differences between the study groups regarding joint pain changes or maximum mouth opening changes. Significant differences were found between the study groups in the reduction of joint sounds upon follow-up after one week (P = 0.009) and one month (P = 0.041), where the guided group had less occurrence of sounds, and the differences disappeared after three months. Conclusions: Within the limits of our study, we find that guidance using ultrasound contributed to a better placement of the injected material within the joint cavity, but there were no significant differences between the two methods concerning joint pain and maximum mouth opening, with a superiority of guidance in managing sounds during follow-up for less than 3 months. Clinical significance of the study: The ultrasound-guided injection into the TMJ can be considered an accurate method, and it has better results in reducing joint sounds.