Faculty Bibliography

WE43 Mg alloy, composed of Mg, Yttrium, Rare Earth elements, and Zirconium, has proved to be a suitable candidate for production of resorbable osteosynthesis implants in both clinical and experimental settings. In a previous study we tested biocompatibility and degradation properties of untreated (as-cast) and artificially aged (T-5) WE43 Mg-alloys as subperiosteal implants on a maxillofacial sheep model. Both the alloy compositions showed excellent biocompatibility, however, with respect to degradation rate, the as-cast form showed increased degradability compared with the T-5. In the present study, we tested the same alloy composition (i.e. as-cast and T-5) to assess their biological behavior and degradation pattern when implanted as endosteal implants on a calvarial bone sheep model. Six implants in form of cylindrical discs were tested in 6 sheep, one per composition of each disc was placed in two monocortical cranial defect created with high speed trephine bur in the parietal bone. After euthanasia at 6 weeks histomorphological analysis of the bone/implant specimens was performed. WE43-as cast showed higher degradation rate, increased bone remodeling, gas pockets formation and osteolysis compared with the T5 alloy. WE43-T5 showed greater bone/implant interface stability, and seemed to be more suitable for fabrication of endosteal bone screws.

INTRODUCTION/BACKGROUND:Parallel to worldwide disparities in patient access to health care, the operative opportunities of surgical trainees are increasingly restricted across the globe. Efforts have been directed toward enhancing surgical education outside the operating room and reducing the wide variability in global trainee operative experience. However, high costs and other logistical concerns may limit the reproducibility and sustainability of nonoperative surgical education resources. METHODS:A partnership between the academic, nonprofit, and industry sectors resulted in the development of an online virtual surgical simulator for cleft repair. First year global access patterns were observed. RESULTS:The simulator is freely accessible online and includes 5 normal and pathologic anatomy modules, 5 modules demonstrating surgical markings, and 7 step-by-step procedural modules. Procedural modules include high-definition intraoperative footage to supplement the virtual animation in addition to include multiple-choice test questions. In its first year, the simulator was accessed by 849 novel users from 78 countries; 70% of users accessed the simulator from a developing nation. CONCLUSION/CONCLUSIONS:The Internet shows promise as a platform for surgical education and may help address restrictions and reduce disparities in surgical training. The virtual surgical simulator presented may serve as the foundation for the development of a global curriculum in cleft repair.

OBJECTIVE:To determine the effects of nasoalveolar molding (NAM) on nasal airway architecture. DESIGN/METHODS:Retrospective case-control study of patients with unilateral cleft lip treated with NAM vs without NAM. SETTING/METHODS:Tertiary referral center specializing in cleft and craniofacial care. Patients, Participants, and Interventions: Thirty-six patients with complete unilateral cleft lip and alveolus: 19 with NAM therapy and 17 without NAM therapy. MAIN OUTCOME MEASURES/METHODS:Cone beam computed tomography (CBCT) scans were compared in multiple coronal sections and were evaluated for linear and angular septal deviation, inferior turbinate hypertrophy, and linear and 2-dimensional airway area. RESULTS:There were no significant differences in linear or angular septal deviation, inferior turbinate area, linear stenosis, or airway area between NAM- and non-NAM-treated patients. CONCLUSIONS:NAM effectively molds the external nasal cartilage and structures but may have limited effects on internal nasal structures.

PURPOSE/OBJECTIVE:The objective of this study was to test the osteogenic capacity of dipyridamole-loaded, three-dimensionally printed, bioactive ceramic (3DPBC) scaffolds using a translational, skeletally mature, large-animal calvarial defect model. MATERIALS AND METHODS/METHODS:Custom 3DPBC scaffolds designed to present lattice-based porosity only towards the dural surface were either coated with collagen (control) or coated with collagen and immersed in a 100 μM concentration dipyridamole (DIPY) solution. Sheep (n = 5) were subjected to 2 ipsilateral trephine-induced (11-mm diameter) calvarial defects. Either a control or a DIPY scaffold was placed in each defect, and the surgery was repeated on the contralateral side 3 weeks later. Following sacrifice, defects were evaluated through microcomputed tomography and histologic analysis for bone, scaffold, and soft tissue quantification throughout the defect. Parametric and non-parametric methods were used to determine statistical significance based on data distribution. RESULTS:No exuberant or ectopic bone formation was observed, and no histologic evidence of inflammation was noted within the defects. Osteogenesis was higher in DIPY-coated scaffolds compared to controls at 3 weeks (p = 0.013) and 6 weeks (p = 0.046) in vivo. When bone formation was evaluated as a function of defect radius, average bone formation was higher for DIPY relative to control scaffolds at both time points (significant at defect central regions at 3 weeks and at margins at 6 weeks, p = 0.046 and p = 0.031, respectively). CONCLUSION/CONCLUSIONS:Dipyridamole significantly improves the calvarial bone regeneration capacity of 3DPBC scaffolds. The most significant difference in bone regeneration was observed centrally within the interface between the 3DPBC scaffold and the dura mater.

This study presents a systematic review of randomized controlled trials (RCTs) in cleft and craniofacial surgery. All studies reporting on RCTs in cleft and craniofacial surgery were identified on PubMed using the search terms "cleft," "velopharyngeal insufficiency," "velopharyngeal dysfunction," "nasoalveolar molding," "gingivoperiosteoplasty," "Pierre Robin sequence," "craniofacial," "craniosynostosis," "craniofacial microsomia," "hemifacial microsomia," "hypertelorism," "Le Fort," "monobloc," "distraction osteogenesis," "Treacher Collins," and "Goldenhar." Studies were excluded if they were not randomized, did not focus primarily on topics related to cleft or craniofacial surgery, included repeat publications of data, or were unavailable in English. Studies were evaluated on demographic and bibliometric data, study size, specific area of focus, and findings reported. Four hundred forty-seven unique studies were identified. One hundred eighty-three papers met inclusion criteria (115 cleft lip and palate, 65 craniofacial, and 3 spanning both disciplines). Sixty-six (36%) were dedicated to topics related to surgical techniques. There were no studies comparing current cleft lip or soft palate repair techniques and no studies on cleft rhinoplasty. The most frequently reported surgical topic was cleft palate. There were several studies on orthognathic techniques which compared distraction osteogenesis to traditional advancement. Most craniofacial operations, such as cranial vault remodeling and frontofacial advancement/distraction, were not represented. Several standard operations in cleft and craniofacial surgery are not supported by Level I evidence from randomized controlled trials. Our community should consider methods by which more RCTs can be performed, or redefine the acceptable standards of evidence to guide our clinical decisions.

OBJECTIVE: To determine the potential risk of visceral injury during Acumed drill iliac crest cancellous bone graft harvest. DESIGN: Radiographic iliac crest anatomic analysis with simulated drill course to measure cancellous bone available for harvest and proximity of vulnerable pelvic structures. SETTING: Single institution, tertiary care university hospital. PATIENTS AND PARTICIPANTS: One hundred pelvic computed tomography scans performed on children 8 to 12 years old without traumatic or neoplastic pathology. INTERVENTIONS: Radiographic simulation of Acumed drill course within iliac bone. MAIN OUTCOME MEASURES: (1) Potential for pelvic visceral injury. (2) Volume of cancellous bone safely available for harvest. RESULTS: Superior and medial cortical thickness at the reference point remained stable across age groups; however, lateral cortical thickness increased with age (3.13 to 3.74 mm, P < .001). Cancellous bone width increased with age at all depths measured (P < .001). Through radiographic simulation, the drill could reach the bowel in 4% of cases and only through gross deviation (>30 degrees ) from the plane of the ilium. There were no cases of simulated bowel perforation within 3 cm of the reference point. The maximum cancellous volume safely harvested increased with age: 24 cc in 8-year-olds to 36 cc in 12-year-olds (P < .001). CONCLUSIONS: Acumed assisted iliac crest bone graft harvest is a safe technique in which substantial amount of cancellous bone can be obtained. The low risk of bowel perforation can be further minimized by limiting the depth of drill bit penetration to less than 3 cm.

BACKGROUND: Infants with craniofacial dysostosis syndromes may present with midface abnormalities but without major (calvarial) suture synostosis and head shape anomalies. Delayed presentation of their calvarial phenotype is known as progressive postnatal craniosynostosis. Minor sutures/synchondroses are continuations of major sutures toward and within the skull base. The authors hypothesized that minor suture synostosis is present in infants with syndromic, progressive postnatal craniosynostosis, and is associated with major suture synostosis. METHODS: The authors performed a two-institution review of infants (<1 year) with syndromic craniosynostosis and available computed tomographic scans. Major (i.e., metopic, sagittal, coronal, and lambdoid) and minor suture/synchondrosis fusion was determined by two craniofacial surgeons and one radiologist using Mimics or Radiant software. RESULTS: Seventy-three patients with 84 scans were included. Those with FGFR2 mutations were more likely to lack any major suture fusion (OR, 19.0; p = 0.044). Minor suture fusion occurred more often in the posterior branch of the coronal arch (OR, 3.33; p < 0.001), squamosal arch (OR, 7.32; p < 0.001), and posterior intraoccipital synchondroses (OR, 15.84; p < 0.001), among FGFR2 versus other patients. Patients (n = 9) with multiple scans showed a pattern of minor suture fusion followed by increased minor and major suture synostosis. Over 84 percent of FGFR2 patients had minor suture fusion; however, six (13 percent) were identified with isolated major suture synostosis. CONCLUSIONS: Minor suture fusion occurs in most patients with FGFR2-related craniofacial dysostosis. Syndromic patients with patent calvarial sutures should be investigated for minor suture involvement. These data have important implications for the pathophysiology of skull growth and development in this select group of patients. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.