Faculty Bibliography

Persistent oral ulcers and erosions can be the final common manifestation, sometimes clinically indistinguishable, of a diverse spectrum of conditions ranging from traumatic lesions, infectious diseases, systemic and local immune-mediated lesions up to neoplasms. The process of making correct diagnosis for persistent oral ulcers still represents a challenge to clinicians. Major diagnostic criteria should include the clinical appearance of both ulcer and surrounding non-ulcerated mucosa, together with the evaluation of associated signs and symptoms, such as: number (single or multiple), shape, severity of the ulcer(s), conditions of remaining mucosa (white, red or with vesiculo-bullous lesions) and systemic involvement (e.g. fever, lymphadenopathy or evaluation of haematological changes). The aim of this paper was to review the literature relating to persistent oral ulcers and provide a helpful, clinical-based diagnostic tool for recognising long-standing ulcers in clinical dental practice. The authors, therefore, suggest distinguishing simple, complex and destroying (S-C-D system) ulcerations, as each requires different diagnostic evaluations and management. This classification has arisen from studying the current English literature relating to this topic, performed using MEDLINE / PubMed / Ovid databases.

A 48-year-old woman with a history of chronic intranasal cocaine abuse presented with unilateral proptosis associated with severe visual loss from optic neuropathy in the right eye. Imaging showed extensive bone and soft tissue destruction in the paranasal region and an orbital mass. Initial biopsies suggested a low-grade neoplasm. The correct diagnosis was established only on repeat biopsy, which revealed marked pleomorphism and nonspecific chronic inflammation with irregular collagen bundles containing thick-walled blood vessels. This case emphasizes that intranasal cocaine abuse may clinically, radiographically, and histopathologically mimic a neoplasm or a necrotizing vasculitis.

OBJECTIVES: We studied the effect of transforming growth factor (TGF)-beta on immortalized human vocal fold fibroblasts. METHODS: Normal human vocal fold fibroblasts were subjected to sequential lentiviral transduction with genes for human telomerase (hTERT) and SV40 large T antigen in order to produce an 'immortalized' cell line of normal phenotype. After confirmation of vocal fold fibroblast transfection, these cells, referred to as HVOX, were treated with various concentrations of exogenous TGF-beta1 and assayed for collagen secretion, migration, and proliferation. In addition, components of the TGF-beta signaling pathway were examined in this cell line. RESULTS: TGF-beta stimulated collagen secretion and migration without altering proliferation of HVOX. HVOX constitutively expressed type I and II TGF-beta receptors, as well as messenger RNA for the Smad signaling proteins and for all TGF-beta isoforms. Exogenous TGF-beta1 induced temporally dependent alterations in Smad2 and Smad3 gene expression. TGF-beta increased Smad7 expression at both 4 and 24 hours. Prolonged exposure to TGF-beta decreased TGF-beta1 gene expression. CONCLUSIONS: Insight into the underlying pathophysiology of vocal fold fibrosis is likely to yield improved therapeutic strategies to mitigate vocal fold scarring. Our data suggest that TGF-beta signaling may be both paracrine and autocrine in this vocal fold fibroblast cell line, and we therefore propose that TGF-beta may be a reasonable target for therapies to prevent and/or treat vocal fold fibrosis, given its putative role in both acute and chronic vocal fold injury, as well as its effects on vocal fold fibroblasts

This paper presents an optimal path planning method of steerable electrode arrays for robot assisted cochlear implant surgery In this paper, the authors present a novel design of steerable electrode arrays that can actively bend at the up An embedded strand in the electrode array provides an active steering degrees of freedom (DoF) This paper addresses the calibration of the steerable electrode arrays and the optimal path planning for inserting it into planar and three dimensional scala tympani models The goal of the path planning is to minimize the intracochlear forces that the electrode array applies on the walls of the scala tympam during insertion This problem is solved by designing insertion path planning algorithms that provide best fit between the shape of the electrode aunty and the curved scala tympani during insertion Optimality measures that account fittape discrepancies between the steerable electrode array and the scala tympam are used to solve for the optimal path planning of the robot Different arrangements of DoF and insertion speed force feedback (ISFF) are simulated and experimentally validated in this paper A quality of insertion metric describing the gap between the steerable electrode array and the scala tympam model is presented and as correspondence to the insertion force is shown The results of using 1DoF 2DoF and 4DoF electrode array insertion setups are compared The 1DoE insertion setup fiver nonsteerable electrode arrays The 2DoF insertion setup uses single axis insertion with steerable electrode arrays. The 4DoF insertion setup allows full control of the insertion depth and the approach angle of the electrode with respect to the cochlea while using steerable electrode arrays It is shown that living steerable electrode arrays significantly reducer the maximal insertion force (59.6% or more) and effectively prevents buckling of the electrode array The 4DoF Insertion setup further reduces the maximal electrode insertion forces The results of using ISFF for steerable electrodes show a slight decrease in the insertion forcer in contrast to a slight increase for nonsteerable electrodes These results show that further research is required in order to determine the optimal ISFF control law and its effectiveness in reducing electrode invention fortes [DOI 10.1115/1.3039513]

Hedgehog signaling is often activated in tumors, yet it remains unclear how GLI2, a transcription factor activated by this pathway, acts as an oncogene. We show that GLI2 is a pleiotropic oncogene. The overexpression induces genomic instability and blocks differentiation, likely mediated in part by enhanced expression of the stem cell gene SOX2. GLI2 also induces transforming growth factor (TGF)B1-dependent transdifferentiation of foreskin and tongue, but not gingival fibroblasts into myofibroblasts, creating an environment permissive for invasion by keratinocytes, which are in various stages of differentiation having downregulated GLI2. Thus, upregulated GLI2 expression is sufficient to induce a number of the acquired characteristics of tumor cells; however, the stroma, in a tissue-specific manner, determines whether certain GLI2 oncogenic traits are expressed

OBJECTIVES: We determined the clinical characteristics and treatment outcomes of an unusual cluster of intracranial complications seen in acute mastoiditis (AM). METHODS: We performed a retrospective review of pediatric patients treated for AM in a tertiary care hospital from March 2006 to March 2007. RESULTS: Eleven children, 6 months to 10 years of age (mean age, 3.8 years), were treated for AM confirmed by computed tomography, which identified asymptomatic intracranial complications in 8 of the 11 patients: these were sigmoid sinus thrombosis (4 patients), epidural abscess (4), perisigmoid abscess or bony erosion (2), and tegmen mastoideum dehiscence (1). All patients required operative intervention with tympanomastoidectomy, although only 2 patients required neurosurgical intervention, consisting of evacuation of epidural abscess and sigmoid sinus thrombosis, respectively. Cultures yielded routine organisms and 1 multidrug-resistant strain of Streptococcus pneumoniae. One patient developed reaccumulation of the subperiosteal abscess that required revision mastoidectomy, and another patient developed postoperative sigmoid sinus thrombosis. CONCLUSIONS: Although uncommon, intracranial complications of AM may present without clinical signs or symptoms. Computed tomography of the temporal bone with contrast is essential for identifying asymptomatic complications. Mastoidectomy remains the mainstay of surgical treatment. Neurosurgical intervention and anticoagulation may be avoided with protracted postoperative intravenous antibiotics. Postoperative vigilance is crucial, as complications may evolve despite aggressive therapy

The business of rhinoplasty has undergone changes in keeping with increased competitive pressures locally, nationally, and internationally. Patient demands and progress in the field have abolished the 'cookie-cutter' nose, with patients now requesting extensive discussions and predictions with computer photoimaging. The R-Factor Question and The D.O.S. Conversation are effective tools in rhinoplasty consultations. These tools provide patients with the clarity of what surgery can do for their lives and help patients overcome the fear produced by the overwhelming amount of information available. By helping our patients achieve the next level of success in their lives, we guarantee ourselves a busy practice filled with happy patients. The rhinoplasty consultation is the key to beginning this relationship of success