This study was conducted on patients who visited Korea University Anam Hospital between January 2016 and June 2018 and were diagnosed with degenerative joint disease and disc displacement with and without reduction on radiographic and clinical evaluation. TMJ arthrocentesis was performed by one surgeon, and mouth opening and the degree of pain before and after the operation were examined. We also investigated whether other treatments (e.g., device therapy) were performed before arthrocentesis. This study was approved by Korea University Anam Hospital in Seoul, South Korea: IRB number 2018AN0427, and informed consent was exempted because this study was a retrospective study.
Inclusion and exclusion criteria
The sample was composed of individuals of both genders older than 15 years. Patients with signs and symptoms of intra-articular TMDs and degenerative joint disease and refractory to conservative treatment were included. They were diagnosed by the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Patients with previous surgery, hypoplasia and/or malignant neoplasm of the mandibular condyle, bone ankylosis, drug allergy, history of psychosomatic illness, or pregnant and lactating patients were excluded.
The mouth opening and degree of pain were measured before TMJ lavage. The first step of TMJ arthrocentesis was extensive disinfection of the surgical site; a line was then drawn connecting the middle portion of the tragus and the outer canthus of the eye.
Articular fossa and eminence were marked at 10 mm and 20 mm respectively, in front of the tragus, along the canthal-tragus line, and vertically bellow at 2 mm and 10 mm respectively. Through palpation of the two reference points, the condyle and articular eminence were marked with methylene blue solution.
To reduce pain when inserting the needle, subcutaneous infiltration anesthesia was performed with 0.5 ml of 2% lidocaine using a dental anesthesia syringe.
After opening the mouth of the patient, a 2-mL saline syringe was inserted with a 26G needle into the upper joint space, and saline was inserted with a gentle force. When 2 mL saline was aspirated again, it indicates that the needle is inserted into the proper place. The second needle was inserted in the same way in the same direction. After the needle was inserted, irrigation was performed for 30 min with 500 mL saline. At this time, the fluid was located at 1.5 m above the patient who is in supine position.
Immediately after surgery, the surgeon injected hyaluronic acid into the operative site of the patient, and the distance between the maxillary and mandibular central incisors was measured to determine the MMO. Pain was recorded using the VAS, which is a subjective assessment. Postoperative MMO and VAS was measured 4 days after the procedure when patients came to the clinic for follow-up. The splint therapy was continued after 4-day follow-up.
CRS and ARS were used to some patients in this study. CRS was used to reduce the bite force and joint load. ARS was used in patients with disc displacement, patients whose symptom persists after physical therapy or joint inflammation, and patients with severe inflammation to reduce the occlusal load. Splints were used prior to arthrocentesis. The period and duration of the appliance use varied depending on each patient’s symptom. Patients with severe symptoms wore the splint for 24 h (less than 1 week), and when the symptoms subsided, they were told to wear the splint during nighttime only.
Muscle relaxant was prescribed to patients with muscle tenderness or pain. Thiosina Tab. (thiocolchicoside 4 mg, aescin 20 mg) was used to patients three times a day. The medicine was prescribed more than 7 days depending on the symptom of the patients. Muscle relaxant was prescribed with painkiller (Somalgen Tab, talniflumate 370 mg) for the same days.
SPSS for Windows® (version 12.0, SPSS Inc., Chicago, IL, USA) was used for statistical analysis. To evaluate the result of arthrocentesis, paired t test was conducted. To compare the result of arthrocentesis categorized by various factors, t test and ANOVA were used. P < 0.05 was considered statistically significant in this study.