Faculty Bibliography

The pharyngeal arch arteries (PAAs) are transient embryonic blood vessels that make indispensable contributions to the carotid arteries and great vessels of the heart, including the aorta and pulmonary arteries. During embryogenesis, the PAAs appear in a craniocaudal sequence to connect pre-existing segments of the primitive circulation after de novo vasculogenic assembly from angioblast precursors. Despite the unique spatiotemporal characteristics of PAA development, the embryonic origins of PAA angioblasts and the genetic factors regulating their emergence remain unknown. Here, we identify the embryonic source of PAA endothelium as nkx2.5(+) progenitors in lateral plate mesoderm long considered to adopt cell fates within the heart exclusively. Further, we report that PAA endothelial differentiation relies on Nkx2.5, a canonical cardiac transcription factor not previously implicated in blood vessel formation. Together, these studies reveal the heart field origin of PAA endothelium and attribute a new vasculogenic function to the cardiac transcription factor Nkx2.5 during great vessel precursor development.

STATEMENT OF PROBLEM: In response to the Commission of Dental Accreditation (CODA) mandate of a competency in the "replacement of teeth including fixed, removable and implant" prostheses, a predoctoral implant curriculum was implemented at New York University College of Dentistry. The assessment of the success or failure of a program should include an assessment of patient satisfaction with the treatment received in the predoctoral clinics. PURPOSE: The purpose of this study was to measure patient satisfaction with the mandibular 2-implant-retained overdenture therapy received in the predoctoral program at New York University College of Dentistry. MATERIAL AND METHODS: A telephone survey of patients who received an implant-retained overdenture in the predoctoral clinics at New York University, College of Dentistry (n=101) was conducted. Two of the authors contacted patients for participation in the survey and, using a prepared script, asked about their satisfaction with items such as function, comfort, and esthetics in addition to their overall satisfaction with the treatment they received. Data were analyzed with descriptive statistics. RESULTS: The study revealed that 79% of participants were satisfied with their masticatory ability, 84% were satisfied with the comfort of the prosthesis, and 89% were satisfied with the esthetics of their new prosthesis. Additionally, 85% of participants reported satisfaction with the overall treatment experience, and 90% would recommend that a friend receive the same treatment. CONCLUSIONS: The results of this study support the incorporation of treatment with an implant-retained mandibular overdenture as part of the routine care provided in the predoctoral education program to meet the mandates of CODA.

Second heart field (SHF) progenitors perform essential functions during mammalian cardiogenesis. We recently identified a population of cardiac progenitor cells (CPCs) in zebrafish expressing latent TGFbeta-binding protein 3 (ltbp3) that exhibits several defining characteristics of the anterior SHF in mammals. However, ltbp3 transcripts are conspicuously absent in anterior lateral plate mesoderm (ALPM), where SHF progenitors are specified in higher vertebrates. Instead, ltbp3 expression initiates at the arterial pole of the developing heart tube. Because the mechanisms of cardiac development are conserved evolutionarily, we hypothesized that zebrafish SHF specification also occurs in the ALPM. To test this hypothesis, we Cre/loxP lineage traced gata4(+) and nkx2.5(+) ALPM populations predicted to contain SHF progenitors, based on evolutionary conservation of ALPM patterning. Traced cells were identified in SHF-derived distal ventricular myocardium and in three lineages in the outflow tract (OFT). We confirmed the extent of contributions made by ALPM nkx2.5(+) cells using Kaede photoconversion. Taken together, these data demonstrate that, as in higher vertebrates, zebrafish SHF progenitors are specified within the ALPM and express nkx2.5. Furthermore, we tested the hypothesis that Nkx2.5 plays a conserved and essential role during zebrafish SHF development. Embryos injected with an nkx2.5 morpholino exhibited SHF phenotypes caused by compromised progenitor cell proliferation. Co-injecting low doses of nkx2.5 and ltbp3 morpholinos revealed a genetic interaction between these factors. Taken together, our data highlight two conserved features of zebrafish SHF development, reveal a novel genetic relationship between nkx2.5 and ltbp3, and underscore the utility of this model organism for deciphering SHF biology.

This qualitative research study identified criteria for clinical teacher quality preferences as perceived by dental students. Third and fourth year dental students at New York University College of Dentistry were given a two question, open-ended survey asking what qualities they liked most and least in a clinical teacher. Responses were collected until data saturation was achieved. A total of 157 respondents provided a total of 995 written comments. Descriptive words within the responses were coded and grouped into key words, according to similar relationships, and further refined into 17 defined categories. Three core themes, Character, Competence and Communication, emerged from these 17 categories, which were validated according to specific references found in the existing educational literature. 'Character' comprised nine of the 17 defined categories: (caring, motivation, empathy, patience, professionalism, available, fairness, happiness, patient-centred) and yielded 59.1% of total student responses; 'Competence' consisted of five categories: knowledgeable, expertise, efficient, skilful, effective (29.2%); and 'Communication' represented the remaining three categories: feedback, approachable and interpersonal communication (11.7%). Positive and negative responses related to the defined category of caring were cited by 59.2% of all students. Motivation was the next highest category, cited by 45.9% of students. Non-cognitive attributes, especially those in the Character theme, comprised the majority of student comments. Because students' perceptions are so critical to understanding clinical teaching effectiveness in dental education, these findings can be used to develop assessments to measure clinical teaching effectiveness, to create criteria for the hiring and promotion of clinical faculty and to plan faculty development programming.

Somites form by an iterative process from unsegmented, presomitic mesoderm (PSM). Notch pathway components, such as deltaC (dlc) have been shown to play a role in this process, while the T-box transcription factors Ntla and Tbx16 regulate somite formation upstream of this by controlling supply and movement of cells into the PSM during gastrulation and tailbud outgrowth. In this work, we report that Ntla and Tbx16 play a more explicit role in segmentation by directly regulating dlc expression. In addition we describe a cis-regulatory module (CRM) upstream of dlc that drives expression of a reporter in the tailbud, PSM and somites during somitogenesis. This CRM is bound by both Ntla and Tbx16 at a cluster of T-box binding sites, which are required in combination for activation of the CRM.

Extraction of teeth leads to bone resorption that can result in asymmetrical hard and soft tissue topography. This article describes a technique to enhance a pontic site in the anterior maxilla by using forced eruption as an alternative to conventional hard and soft tissue augmentation surgeries. Forced eruption is a well-known procedure and its use in developing a pontic site for a fixed dental prosthesis is described in this clinical report.

BACKGROUND: In 2002 and 2009, two consensus statements-one from a symposium in Canada and one from England-were issued that recommended that the first-choice standard of care for an edentulous mandible should be the two implant-retained mandibular overdenture (IRMOD). The authors conducted a survey to determine if, in 2011, U.S. academic prosthodontic experts' opinions were aligned with those in the two consensus statements. METHODS: The authors administered a Delphi method survey to an expert panel of 16 nationally representative academic prosthodontists to determine if there is consensus on the first-choice standard of care for an edentulous mandible between the IRMOD and a conventional mandibular complete denture (CD). Consensus agreement was defined as a 70 percent agreement level among the panelists. RESULTS: The panel attained consensus favoring the IRMOD for nine of the 10 parameters assessed-retention, stability, speech, masticatory efficiency, comfort while eating soft foods and hard foods, confidence in intimate situations, satisfaction and self-esteem. The exception was esthetics for which only a majority (51-69 percent) favored the IRMOD. CONCLUSIONS: The panelists reached consensus that they would recommend an IRMOD instead of a CD as the first-choice standard of care for patients who are healthy or have mild systemic disease, but not for patients with severe systemic disease. CLINICAL IMPLICATIONS: Surveyed academic prosthodontists recommend an IRMOD as the first choice standard of care when restoring an edentulous mandible of a healthy patient or a patient with mild systemic disease.

Treatment with fixed and removable partial dentures has been the traditional method of addressing the replacement of teeth competencies in dental education. However, by 2013 the Commission on Dental Accreditation (CODA) standards will mandate a competency in "replacement of teeth including fixed, removable, and dental implants." In 2005, New York University College of Dentistry implemented a comprehensive implant program for predoctoral dental students. One of the outcome assessments of this program was to determine the level of patient satisfaction. Therefore, a patient satisfaction survey (n=103) assessed the use of implant treatment for the restoration of partially edentulous patients, measuring such dimensions of satisfaction as function, comfort, and esthetics. The results revealed that 96 percent of the patients surveyed were satisfied with their ability to chew, 91 percent were satisfied with the comfort of their restoration, and 86 percent were satisfied with the appearance of their restoration. Additionally, 90 percent of the surveyed patients who received implant-retained crowns as part of their routine care were satisfied with the overall treatment experience, and 97 percent of them would recommend this treatment to a friend. The survey results validate implant-supported crown treatment in predoctoral education. Although implant-supported restorations are a valid treatment option that must be presented to patients during treatment planning, creating a clinical competency in implant therapy requires greater consideration. Therefore, the benefits and challenges of such a clinical competency are discussed.

Using an expanded definition of scholarship that goes beyond the scholarship of discovery (research) to include the scholarship of integration, the scholarship of application, and the scholarship of teaching, this article explains interrelationships among these scholarship types in health professions and specifically dental education. Such interrelationships can lead to meaningful expansion of scholarship especially in the form of translational research, which relies on the development of all four of these types of scholarship. In recent years, health care-related organizations have been seeking ways to expand translational research. At the same time, an increasing number of academic institutions have been considering how to redefine what qualifies as advancing one's discipline in ways that go beyond mere number of publications and grants to better reflect the faculty member's overall scholarly effort. These redefinitions and a new attention to scholarly collaboration have led to the concept of a 'complete scholar': one who makes contributions in all four areas of scholarship by collaborating with other scholars, practitioners, and members of the community. Expanding the concept of a complete scholar to that of a 'complete institution' is the basis for what we propose as a Model of Institutional Scholarship. This model is exemplified by the Cochrane Collaboration, a gold standard for a complete vision of research on evidence-based health care. In the Model of Institutional Scholarship, an institution can visualize, plan, develop, and orchestrate all scholarship being conducted within its realm, creating collaborations among individual efforts that will enhance effectiveness and the creation of new knowledge