Background: Tumors of the mandible are complex, often requiring replacement of bone, soft tissue, and teeth. The fibula flap has become a routine procedure in large tumors of the jaw, providing bone and soft tissue at the time of the resection. In current practice, dental reconstruction is delayed for 3 to 6 months, leaving the patient without teeth in the interim. This can be disfiguring and anxiety provoking for the patient. Methods: In this article, the authors present three patients with benign tumors of the mandible who underwent virtually guided resection, fibula reconstruction, and insertion of an implant-retained dental prosthesis in one operation. In addition, the authors report their early experience using this technique in the maxilla. Results: The authors present a case series of three patients with benign mandibular tumors and one patient with a benign maxillary tumor who underwent total reconstruction using computer-aided design and computer-aided manufacturing technology in a single stage. Conclusions: In the right situation, total mandibular reconstruction is possible in a single stage. This is demonstrated by the successful outcomes of these patients. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

Bony defects in the craniomaxillofacial skeleton remain a major and challenging health concern. Surgeons have been trying for centuries to restore functionality and aesthetic appearance using autografts, allografts, and even xenografts without entirely satisfactory results. As a result, physicians, scientists, and engineers have been trying for the past few decades to develop new techniques to improve bone growth and bone healing. In this review, the authors summarize the advantages and limitations of current animal models; describe current materials used as scaffolds, cell-based, and protein-based therapies; and lastly highlight areas for future investigation. The purpose of this review is to highlight the major scaffold-, cell-, and protein-based preclinical tools that are currently being developed to repair cranial defects.

The free fibula osteocutaneous flap has become the criterion standard for reconstruction of complex mandibular defects. The authors present their institutional experience with optimization of flap contouring and inset using virtual planning and prefabricated cutting jigs. All free fibula-based mandible reconstructions performed at the authors' institution using virtual planning technology between 2009 and 2012 were retrospectively analyzed. The authors evaluated a variety of patient and procedural variables and outcomes. A series of cases performed before virtual planning was reviewed for comparison purposes. Fifty-four reconstructions were performed in 52 patients. Patients were divided evenly between a private university-affiliated medical center and a large county hospital. The most common indications were malignancy (43 percent), ameloblastoma (26 percent), and osteonecrosis/osteomyelitis (23 percent). Thirty percent of patients had irradiation of the recipient site and 38 percent had previous surgery. Sixty-three percent of patients received dental implants, with 47 percent achieving functional dentition. Twenty-five percent of patients had immediate dental implant placement, and 9 percent had immediate dental restoration. Postoperative imaging demonstrated excellent precision and accuracy of flap positioning. Comparison with cases performed before virtual planning demonstrated increased complexity of flap design along with reduced operative time in the virtually planned group. Preoperative virtual planning along with use of prefabricated cutting jigs allows for precise contouring and positioning of microvascular fibula free flaps in mandibular reconstruction. Using this technique, the authors have achieved unprecedented rates of dental rehabilitation along with reduced operative times. The authors believe that virtual planning technologies are an emerging criterion standard in mandible reconstruction. Therapeutic, IV.

The goal of this article was to illustrate the ease in which virtual surgery and computer-aided design and manufacturing can be used by the craniomaxillofacial surgeon to create tremendously accurate postoperative results and provide confidence with even the most complex three-dimensional bony reconstructions. With advancements in software technology and three-dimensional printing, our ability to plan and execute precise bony reconstruction has become a reality. With this technology, guides can be made to ensure exact bony repositioning or replacement. These guides can help guide cutting of the bone and can act as splints to precisely reposition the bone and direct plate placement. With use of these computer-aided design and manufacturing guides and the addition of guidance technology, the position of the bone can be guaranteed intraoperatively. We review our unique and advanced method in approaching some of these problems and illustrate the application of these techniques in mandibular reconstruction, orthognathic surgery, maxillofacial trauma, and temporomandibular joint reconstruction. This technology continues to evolve, and our indications for its application continue to grow. This article represents only a small portion of the types of cases in which these techniques have already been applied.

Angiogenesis is essential for the increased delivery of oxygen and nutrients required for the reparative processes of bone healing. Vascular endothelial growth factor (VEGF), a potent angiogenic growth factor, has been implicated in this process. We have previously shown that hypoxia specifically and potently regulates the expression of VEGF by osteoblasts. However, the molecular mechanisms governing this interaction remain unknown. In this study, we hypothesized that the hypoxic regulation of VEGF expression by osteoblasts occurs via an oxygen-sensing mechanism similar to the regulation of the erythropoietin gene (EPO). To test this hypothesis, we examined the kinetics of oxygen concentration on osteoblast VEGF expression. In addition, we analyzed the effects of nickel and cobalt on the expression of VEGF in osteoblastic cells because these metallic ions mimic hypoxia by binding to the heme portion of oxygen-sensing molecules. Our results indicated that hypoxia potently stimulates VEGF mRNA expression. In addition, we found that nickel and cobalt both stimulate VEGF gene expression in a similar time- and dose-dependent manner, suggesting the presence of a hemelike oxygen-sensing mechanism similar to that of the EPO gene. Moreover, actinomycin D, cycloheximide, dexamethasone, and mRNA stabilization studies collectively established that this regulation is predominantly transcriptional, does not require de novo protein synthesis, and is not likely mediated by the transcriptional activator AP-1. These studies demonstrate that hypoxia, nickel, and cobalt regulate VEGF expression in osteoblasts via a similar mechanism, implicating the involvement of a heme-containing oxygen-sensing molecule. This may represent an important mechanism of VEGF regulation leading to increased angiogenesis in the hypoxic microenvironment of healing bone.

The tear trough and the lid/cheek junction become more visible with age. These landmarks are adjacent, forming in some patients a continuous indentation or groove below the infraorbital rim. Numerous, often conflicting procedures have been described to improve the appearance of the region. The purpose of this study was to evaluate the anatomy underlying the tear trough and the lid/cheek junction and to evaluate the procedures designed to correct them. Twelve fresh cadaver lower lid and midface dissections were performed (six heads). The orbital regions were dissected in layers, and medical photography was performed. In the subcutaneous plane, the tear trough and lid/cheek junction overlie the junction of the palpebral and orbital portions of the orbicularis oculi muscle and the cephalic border of the malar fat pad. In the submuscular plane, these landmarks differ. Along the tear trough, the orbicularis muscle is attached directly to the bone. Along the lid/cheek junction, the attachment is ligamentous by means of the orbicularis retaining ligament. The tear trough and lid/cheek junction are primarily explained by superficial (subcutaneous) anatomical features. Atrophy of skin and fat is the most likely explanation for age-related visibility of these landmarks. "Descent" of this region with age is unlikely (the structures are fixed to bone). Bulging orbital fat accentuates these landmarks. Interventions must extend significantly below the infraorbital rim. Fat or synthetic filler may be best placed in the intraorbicularis plane (tear trough) and in the suborbicularis plane (lid/cheek junction).