Use of computer-assisted templates for placement of osteotomies in lateral gap arthroplasty.

PURPOSE: To evaluate the effectiveness of computer-generated surgical templates for precise bone removal in the treatment of temporomandibular joint (TMJ) ankylosis with a medially displaced condyle. MATERIALS AND METHODS: Patients found to have a medially displaced condylar head and lateral bony fusion from January 2012 through January 2014 were included in the study. ProPlan CMF 1.4 software (Materialise Medical, Leuven, Belgium) was used to design the osteotomies for the lateral bony fusion and protect the medial condylar head. Surgical templates were fabricated to transfer the design to the operation and effectiveness was evaluated postoperatively using computed tomographic (CT) scan comparisons. RESULTS: In 5 surgeries with a total of 7 joints, the surgical templates fit well and accurately guided the osteotomies. The skull base, external auditory canal, major vessels, and residual condyle were well protected. Postoperative CT difference analysis calculated an average difference of 1.044 mm. CONCLUSIONS: Computer-assisted surgical templates accurately guided bone removal and protected the residual condylar head, skull base, and external auditory canal in the treatment of TMJ ankylosis.

Modified temporomandibular joint disc repositioning with miniscrew anchor: part I--surgical technique.

Anterior disc displacement is one of the most common conditions affecting the temporomandibular joint. In the authors' previous publications, they reported on the basic technical elements of disc repositioning surgery. However, the present article presents some critical modifications that have allowed the safe and successful performance of this procedure during the past 3 years.

Juxta-articular Myxoma of the Temporomandibular Joint.

The juxta-articular myxoma represents a benign mesenchymal neoplasm that arises from tissue within or adjacent to a joint space. There have been a number of reported cases involving myxomas of the knee, shoulder, elbow, wrist, and hip. To our knowledge there, however, have been no reported cases of juxta-articular myxomas of the temporomandibular joint (TMJ). This report describes the case of a 57-year-old woman with a juxta-articular myxoma of the left TMJ extending into the infratemporal fossa (ITF). Access to the tumor was accomplished via a preauricular incision and low condylar osteotomy which allowed for displacement of the condyle for direct visualization and excision of the tumor. The postoperative course was benign and the patient demonstrated no cosmetic or functional limitation. Likewise, follow-up at 30 months showed no evidence of recurrence. Benign encapsulated tumors of the ITF can be effectively accessed by means of a modified preauricular incision, low condylar osteotomy, and anterior meniscal release. This direct approach allows for excellent surgical exposure, minimal surgical site morbidity, and maintenance of physiologic joint function and occlusion.

Application of digital templates to guide total alloplastic joint replacement surgery with biomet standard replacement system.

PURPOSE: To design and manufacture digital templates to guide Biomet total alloplastic joint replacement surgery (Biomet, Warsaw, IN) and evaluate the clinical efficacy. MATERIALS AND METHODS: Six patients who underwent total alloplastic joint replacement surgery from November 2013 to March 2014 were included in this study. Before surgery, the Biomet standard prostheses were scanned and imported into the ProPlan CMF 1.4 software (Materialise NV, Leuven, Belgium) for virtual positioning and osteotomy planning. Digital templates were then designed to guide intraoperative bone trimming and prosthesis placement. A postoperative computed tomography scan was taken and used to measure how well the postsurgical images corresponded to the images generated in the preoperative plan. RESULTS: The digital templates were smoothly positioned and easily adapted, and they accurately guided bone trimming and prosthesis implantation. In addition, vital anatomic structures such as the skull base and inferior alveolar neurovascular bundle were not injured during the procedures. The result of the merged postoperative and preoperative computed tomography scans showed that the position of the prostheses corresponded quite accurately to the preoperative design, with an error of 1.139±0.183 mm. CONCLUSIONS: Digital templates can accurately guide the bone trimming required for placement of Biomet total alloplastic joints. Likewise, these templates help place the prostheses in the desired locations, enhance stability, and avoid damage to the skull base and inferior alveolar neurovascular bundle.