Faculty Bibliography

This article focuses on flap-related complications after creation of a neophallus for transgender individuals. It outlines the most frequently used flaps for this procedure and how flap-related complications can affect the overall outcome of the phalloplasty. With surgeons staging the procedure in different stages, it is important to understand the different strategies and the implication a flap-related complication can have on the end result and how it may be prevented.

Current pharmacologic regimens in transplantation prevent allograft rejection through systemic recipient immunosuppression but are associated with severe morbidity and mortality. The ultimate goal of transplantation is the prevention of allograft rejection while maintaining recipient immunocompetence. We hypothesized that allografts could be engineered ex vivo (after allotransplant procurement but before transplantation) by using mesenchymal stem cell-based therapy to generate localized immunomodulation without affecting systemic recipient immunocompetence. To this end, we evaluated the therapeutic efficacy of bone marrow-derived mesenchymal stem cells in vitro and activated them toward an immunomodulatory fate by priming in inflammatory or hypoxic microenvironments. Using an established rat hindlimb model for allotransplantation, we were able to significantly prolong rejection-free allograft survival with a single perioperative ex vivo infusion of bone marrow-derived mesenchymal stem cells through the allograft vasculature, in the absence of long-term pharmacologic immunosuppression. Critically, transplanted rats rejected a second, nonengineered skin graft from the same donor species to the contralateral limb at a later date, demonstrating that recipient systemic immunocompetence remained intact. This study represents a novel approach in transplant immunology and highlights the significant therapeutic opportunity of the ex vivo period in transplant engineering.

BACKGROUND:While the US population overall has experienced improvements in oral health over the past 60 years, oral diseases remain among the most common chronic conditions across the life course. Further, lack of access to oral health care contributes to profound and enduring oral health inequities worldwide. Vulnerable and underserved populations who commonly lack access to oral health care include racial/ethnic minority older adults living in urban environments. The aim of this study was to use a systematic approach to explicate cause and effect relationships in creating a causal map, a type of concept map in which the links between nodes represent causality or influence. METHODS:To improve our mental models of the real world and devise strategies to promote oral health equity, methods including system dynamics, agent-based modeling, geographic information science, and social network simulation have been leveraged by the research team. The practice of systems science modeling is situated amidst an ongoing modeling process of observing the real world, formulating mental models of how it works, setting decision rules to guide behavior, and from these heuristics, making decisions that in turn affect the state of the real world. Qualitative data were obtained from focus groups conducted with community-dwelling older adults who self-identify as African American, Dominican, or Puerto Rican to elicit their lived experiences in accessing oral health care in their northern Manhattan neighborhoods. RESULTS:The findings of this study support the multi-dimensional and multi-level perspective of access to oral health care and affirm a theorized discrepancy in fit between available dental providers and patients. The lack of information about oral health at the community level may be compromising the use and quality of oral health care among racial/ethnic minority older adults. CONCLUSIONS:Well-informed community members may fill critical roles in oral health promotion, as they are viewed as highly credible sources of information and recommendations for dental providers. The next phase of this research will involve incorporating the knowledge gained from this study into simulation models that will be used to explore alternative paths toward improving oral health and health care for racial/ethnic minority older adults.

Face transplantation has evolved over the last 12 years into a safe and feasible reconstructive solution, with good aesthetic and functional outcomes for patients with severe facial defects who are not amenable to reconstruction through conventional and autologous approaches. Among patients who underwent face transplantation to date, a significant proportion did so following trauma, mostly ballistic and thermal injuries. It is therefore important for trauma surgeons who deal with these injuries regularly to be familiar with the literature on face transplantation following traumatic injuries. In this study, we provide a focused review on this topic, with an emphasis on highlighting the limitations of conventional craniomaxillofacial reconstruction, while emphasizing data available on the risks, benefits, surgical indications, contraindications, as well as aesthetic and functional outcomes of face transplantation. The authors also provide an update on all face transplants performed to date including traumatic mechanisms of injury, and extent of defects. They finally describe 2 cases performed by the senior author for patients presenting with devastating facial ballistic and thermal injuries. The authors hope that this work serves as an update for the trauma surgery community regarding the current role and limitations of face transplantation as a craniomaxillofacial reconstructive option for their patient population. This can potentially expedite the reconstructive process for patients who may benefit from face transplantation.

Facial transplantation (FT) has attracted the interest of individuals with facial disfigurement as a path to social reintegration. The perception among face transplant recipients and the reconstructive surgery community appears to be that superior functional and esthetic outcomes can be obtained with FT compared to autologous reconstruction (AR). Although lifelong immunosuppression adds well-known risks to FT, its benefits have proven difficult to quantify, especially because of its non-life-saving nature. Evidence that the general public perceives facial allograft recipients as less disfigured than AR patients may dramatically alter the currently accepted risk/benefit ratio of this novel procedure. A survey containing independent images of individuals in nondisfigured (ND), autologous facial reconstruction, and FT groups was administered to the general public in an urban environment. Participants assigned a disfigurement score to each photograph using the Observer-Rated Facial Disfigurement Scale, a validated instrument used to rate facial disfigurement among head and neck cancer patients. One-way analysis of variance was used to calculate differences in mean level of perceived facial disfigurement among the 3 groups. A total of 250 participants completed the survey. Mean perceived disfigurement scores assigned to the ND, FT, and AR groups were 1.2 ± 0.4, 4.9 ± 1.3, and 8.5 ± 0.6, respectively. A significant difference in disfigurement score was observed between all 3 groups (P < 0.001). This pilot study suggests that the general public perceives the esthetic outcome of FT to be superior to those obtained with AR in patients with severe facial defects.

This study evaluated the influence of polishing protocols on the surface roughness of flowable and regular bulk fill composites. Five bulk fill composites were tested: SureFil SDR Flow (SDR), Tetric EvoFlow Bulk fill (TEF), Filtek Bulk Fill Flowable (FIF), Tetric EvoCeram Bulk Fill (TEC), and Filtek Bulk Fill Posterior (FIP). Two polishing protocols were tested: Sof-Lex and Astropol. Astropol created a smoother surface for FIP (P < .05); however, the polishing protocol did not influence surface roughness on TEC (P > .05). SDR, TEF, and FIF exhibited rougher surfaces when polished. Sof-Lex created rougher surfaces for bulk fill composites. It was concluded that surface roughness was related to material composition rather than the polishing system.

Background/UNASSIGNED:Widespread application of vascularized composite allotransplantation (VCA) is currently limited by the required lifelong systemic immunosuppression and its associated morbidity and mortality. This study evaluated the efficacy of ex vivo (after procurement but before transplantation) engineering of allografts using small interfering RNA to knockdown major histocompatibility complex I (MHC-I) and prolong rejection-free survival. Methods/UNASSIGNED:Endothelial cells (ECs) were transfected with small interfering RNA targeted against MHC-I (siMHC-I) for all in vitro experiments. MHC-I surface expression and knockdown duration were evaluated using quantitative polymerase chain reaction (qPCR) and flow cytometry. After stimulating Lewis recipient cytotoxic lymphocytes (CTL) with allogeneic controls or siMHC-I-silenced ECs, lymphocyte proliferation, CTL-mediated and natural killer-mediated EC lysis were measured. Using an established VCA rat model, allografts were perfused ex vivo with siMHC-I before transplantation. Allografts were analyzed for MHC-I expression and clinical/histologic evidence of rejection. Results/UNASSIGNED:< 0.05). Conclusions/UNASSIGNED:Ex vivo siMHC-I engineering can effectively modify allografts and significantly prolong rejection-free allograft survival. This novel approach may help reduce future systemic immunosuppression requirements in VCA recipients.