Virtual Surgical Planning for Oral and Maxillofacial Surgery

For patients requiring complex craniofacial congenital and oncologic deformity correction and orthognathic surgeries, precise treatment planning is of the utmost importance. At Mount Sinai’s Division of Oral and Maxillofacial Surgery, we utilize state-of-the-art technology to assist in our surgical planning. Our digital X-ray system and cone beam technology assist us with determining the exact diagnosis and obtaining a 3-dimensional model for surgical treatment planning. This radiographic technology then enables our surgeons to use virtual surgical planning (VSP) to plan various surgical procedures. Additionally, we use 3D printed models of the jaw, particularly for jaw reconstruction procedures, which assist with adapting plates and contouring the bone flaps when in the OR.

Mount Sinai has been at the forefront of employing VSP since 2008 –closely collaborating with a technology company from Belgium to devise surgical workflows - and our team is currently one of only a handful across the nation planning advanced oral surgery cases with it. VSP is a computer program that serves to accurately perform a procedure on a computer generated model. This technology can be applied to the placement of dental implants, advanced jaw repositioning procedures (orthognathic surgery), congenital deformities, and jaw reconstruction requiring sophisticated bone grafting. The use of VSP for complex oral and maxillofacial surgeries is becoming a routine component of our treatment planning process across the Mount Sinai Health System, so all of our patients can experience the best possible outcome.

What to Expect at Your Oral Imaging Appointment

A comprehensive initial workup is performed on each patient who is a candidate for VSP. This includes facial photographs (3D), intraoral photographs, facial measurements, midline notations, occlusion class notation, plain films, study models, a bite registration, and a cone beam CT scan. Once all the data is gathered, a cephalometric analysis (showing the dental and skeletal relationships in the head) is performed with the patients’ clinical findings in mind, resulting in a personalized problem list and treatment plan for the patient.

How We Build Patient Treatment Plans Using VSP

Upon obtaining the imaging, the patient data is then digitized and 3D virtual models are rendered. The goal is to simulate the planned surgical movements on the 3D model based on the pre-op analysis and individualized problem list. This is quite flexible and user friendly, as the software can show different colors of the skull, partitioning the surgical planes. After the movements are achieved on the 3D computer rendition, plastic surgical guides are fabricated using a 3D printer, allowing us to execute the plan in the OR. These guides are used during the surgery to ensure the precise repositioning of the jaws.

In the case of mandibular reconstruction, we create a 3D virtual model of the jaw. We then use a virtual resection plane tool to create a new object consisting of the jaw segment that needs to be removed due to the tumor invasion. We then bring the CT scan of the patient’s fibula (calf bone) and create the cuts to restore the jaw to the same form before the surgery using the object as a guide. This enables us to shape the fibula perfectly and create accurate, patient specific plates, as per the plan.

Patient Benefits of VSP

An additional benefit of VSP is that patients appreciate the communication and clarity offered with VSP because they can visualize exactly what we are going to be doing in the OR. A physician can draw a sketch on a piece of paper to explain it, but when we show patients a 3D rendering of their own jaw with the tumor and the proposed surgical plan to remove, it puts the entire procedure into perspective. In addition to better communication and education about complex reconstructive procedures, patient benefits include:

• Increased individualized care
• Less operating time (VSP can eliminate up to 45 minutes on a reconstruction case and several hours of orthognathic  pre-op planning)
• Fewer intraoperative ”surprises”
• More predictable and better outcomes – the guide enables our surgeons to double check the planned operative movements

Finally, clinical results using this technology have been outstanding. We conducted a VSP outcomes study by comparing the actual amount of maxillary anterior movement achieved in the OR to the predicted VSP measurement derived preoperatively. Upon performing a retrospective analysis of 20 orthognathic cases over 18 months, the results of this analysis revealed a level of accuracy with a standard deviation for all of the procedures at 0.27 mm from the predicted value, confirming the accuracy of this method of surgical planning and the betterment of outcomes using it.