Repair of complex ovine segmental mandibulectomy utilizing customized tissue engineered bony flaps.

Craniofacial defects require a treatment approach that provides both robust tissues to withstand the forces of mastication and high geometric fidelity that allows restoration of facial architecture. When the surrounding soft tissue is compromised either through lack of quantity (insufficient soft tissue to enclose a graft) or quality (insufficient vascularity or inducible cells), a vascularized construct is needed for reconstruction. Tissue engineering using customized 3D printed bioreactors enables the generation of mechanically robust, vascularized bony tissues of the desired geometry. While this approach has been shown to be effective when utilized for reconstruction of non-load bearing ovine angular defects and partial segmental defects, the two-stage approach to mandibular reconstruction requires testing in a large, load-bearing defect. In this study, 5 sheep underwent bioreactor implantation and the creation of a load-bearing mandibular defect. Two bioreactor geometries were tested: a larger complex bioreactor with a central groove, and a smaller rectangular bioreactor that were filled with a mix of xenograft and autograft (initial bone volume/total volume BV/TV of 31.8 ± 1.6%). At transfer, the tissues generated within large and small bioreactors were composed of a mix of lamellar and woven bone and had BV/TV of 55.3 ± 2.6% and 59.2 ± 6.3%, respectively. After transfer of the large bioreactors to the mandibular defect, the bioreactor tissues continued to remodel, reaching a final BV/TV of 64.5 ± 6.2%. Despite recalcitrant infections, viable osteoblasts were seen within the transferred tissues to the mandibular site at the end of the study, suggesting that a vascularized customized bony flap is a potentially effective reconstructive strategy when combined with an optimal stabilization strategy and local antibiotic delivery prior to development of a deep-seated infection.

Unusual Case of a Massive Macroglossia Secondary to Myxedema: A Case Report and Literature Review.

Macroglossia is classified as true macroglossia, which exhibits abnormal histology with clinical findings, and relative macroglossia, in which normal histology does not correlate with pathologic enlargement. This report describes an atypical case of morbidity with massive macroglossia secondary to myxedema; the macroglossia enlarged over a 3-month period before being presented to the Department of Oral and Maxillofacial Surgery, University of Texas Health Science Center at Houston (Houston, TX). Substantial enlargement of the tongue (16 cm long × 10 cm wide) was first attributed to angioedema, which was refractory to the discontinuation of lisinopril and a C1 esterase inhibitor. A core tongue biopsy examination was performed to rule out angioedema, amyloidosis, myxedema, and idiopathic muscular hypertrophy. Interstitial tissue was positive for Alcian blue and weakly positive for colloidal iron, which are correlated with hypothyroidism and a diagnosis of myxedema. However, the macroglossia did not resolve after correcting for hypothyroidism. The patient required a wedge glossectomy for definitive treatment. She recovered unremarkably, with excellent cosmesis and preservation of lingual and hypoglossal function. There are some case reports of massive macroglossia but none with myxedema as the primary etiology.

Oculocardiac Reflex in an Orbital Fracture Without Entrapment.

Large orbital fractures in older patients are infrequently associated with an exaggerated oculocardiac reflex. This report describes the case of a patient in his 40s with a large right orbital floor and medial wall fracture without radiographic evidence of extraocular muscle compression or entrapment who developed severe nausea and bradycardia with movement of his affected eye. The patient exhibited bradycardia to 17 beats per minute during the initial examination and was taken urgently to the operating room for reconstruction of the right orbital floor and medial wall. Additional episodes of bradycardia intraoperatively were responsive to glycopyrrolate. After the procedure, the patient's pain was decreased, a normal range of motion was restored, and the bradycardia and nausea resolved. An explanation for induction of the oculocardiac reflex is considered in the absence of clinical or radiologic entrapment because large orbital fractures are not often considered to induce this reflex.