oral and facial health . In these cases , orthognathic surgery may be needed to reposition the jaws .
When patients are considering orthognathic surgery , the team uses sophisticated three-dimensional digital imaging technology to illustrate exactly how the jaws will be repositioned . They use comprehensive digital facial and oral photographs , large field-of-view CBCT and digital full-arch intraoral scans to simulate the anticipated improvement in occlusion , airway , function and appearance . This helps patients more fully understand the surgical process , and to visualize the benefits they can expect . Patients receive a portfolio of these images and a prediction of their profile after surgery . Once treatment is complete , patients also receive a series of digital photographs comparing their preoperative , prediction , and postoperative appearance . Virtually without exception , patients prefer their actual post-treatment appearance over the computer-generated prediction .
Dr . Bates has participated in , and provided the patient data for , several studies performed by residents in the Department of Orthodontics at the former Baylor College of Dentistry evaluating dozens of patients undergoing orthognathic surgery , comparing computer-generated treatment plans with actual outcomes , and looking at both hard tissue landmarks ( bone and teeth ) and soft tissue ( lips , chin and nose ). These studies support the predictability and reliability of the techniques developed by Dr . Bates for orthognathic treatment planning .
At an extended preoperative appointment , patients undergo full facial and intraoral digital imaging , CBCT and intraoral scans , as well as extensive pre-and postoperative counseling , nutritional consultation , and informed consent . Digital STL files are segmented as necessary and occlusal analysis and adjustments are made .
At this point , Dr . Bates meets virtually with the multidisciplinary team treating the patient , always an orthodontist , and
The operating room is equipped with both medical ( dry ) and dental ( wet ) vacuum systems , and dual , ceiling-mounted , high-intensity surgical lights , a laminar air-flow system , seamless flooring , and an external , hands-free scrub sink .
often also including the restorative dentist or other dental specialists such as a prosthodontist , periodontist or endodontist . Once the treatment plan is approved at the team conference , surgical splints and guides are 3D printed . This process eliminates all guesswork in the operating room and provides a level of predictability previously unattainable in orthognathic surgery .
Distraction Osteogenesis
Reconstructive surgery also includes other procedures to correct occlusion , augment bone and soft tissue , and replace diseased functional components such as the temporomandibular joint . Dr . Bates has extensive experience with distraction osteogenesis , a method of gradually extending bone using distraction forces . Dr . Bates was among the earliest adopters of the techniques of distraction osteogenesis to grow new alveolar bone and lengthen deficient bones such as the mandible . “ I was strongly influenced in this area by several colleagues and really encouraged to stretch this envelope . Based on their recommendations and input , we developed an entirely intraoral , bone-borne procedure based on a nerve-sparing ramus osteotomy technique which became highly successful for lengthening the mandible in growing kids , and allowed us to totally avoid the developing teeth .”
Stereolithographic Models
Many cases involving complex reconstructive needs benefit from fabrication of a stereolithographic model for design and fabrication of custom implants , such as TMJ implants , distraction appliances or implants for cosmetic or reconstructive facial bone augmentation . A CBCT of the patient is performed and sent to a lab for fabrication of the model . “ These 3D models are invaluable in treatment planning and implant design , and we
Photo by Ray Bryant , Bryant Studios
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