Evaluation of Accuracy of Computer Guided Arthrocentesis of Temporomandibular Joint for Patients With Anterior Disc Displacement With Reduction Using Patient Specific Guide (Case Series)

A consecutive, single centered prospective study. All the patients will be selected from the Outpatient Clinic of the Oral and Maxillofacial Surgery Department. Faculty of dentistry- Cairo University Egypt.

Patients will be subjected to:

• Case history including personal data, medical, surgical and family history.
• Clinical examination
• Radiographic examination using magnetic resonance imaging (MRI) and computed tomography (C.T) bony and soft tissue window.
• Diagnostic studying casts, laser scanning of the casts in centric occlusion
• Preoperative anaesthesia assessment for fitness for general anaesthesia.
• Utilizing computer aided surgical simulation software a patient specific surgical guide is designed from the patients' segmented 3D soft tissue window with the following criteria:
• and fabrication of the surgical guide using c.t. scan with soft tissue and bony window, segmentation of the 3D model using Mimics 19.0 (medical engineering program), designing a 3D patient specific the guide is resting on skin of buccal and temporal area and occlusal bite block with a 3 openings i. The guide is resting on skin of buccal and temporal area and occlusal bite block with 3 openings ii. 2 depth controlled cylinders for input and output needles iii. 1 cylinder for arthroscopy trocar arm for verification of needle tip location in the superior joint space
• Then exporting the stl file to 3D printing machine before surgery All cases will undergo surgery under general anesthesia. The patient specific guide will be adapted on facial soft tissue overlying the temporomandibular joint . Fixation of the guide using occlusal bite-block on maxillary and mandibular teeth. Insertion of arthroscopic trocar through the depth controlled cylinder. Locating the superior joint space using arthroscopy. Insertion of input needle through the depth controlled cylinder. Verification of the needle position and angulation in the superior joint space by the arthroscopy. Infusion of 2ml lactated Ringer's solution then insertion of output needle and joint effusion by 300 ml of lactated Ringer's solution then infusing the joint by 2ml of hyaluronic acid.

Proper postoperative instructions will be given to the patient as soft diet for 1 week and immediate postoperative physiotherapy from the second day of operation and for 1 month. in addition to the postoperative medications including antibiotics (amoxicillin 500mg capsules t.i.d) and analgesics (diclofenac potassium 50mg as needed).Adherence to follow ups is also instructed