Faculty Bibliography

Incorporation of bioceramics on the surface of dental implants has been utilized in an attempt to increase biological response of bone to materials. This paper reports the in vitro biological evaluation of Ca/P-based nanothickness bioceramic coated alumina-blasted/acid-etched titanium implants (AB/AE nanotite implant) and compare its performance to the untreated and uncoated implants, Ca/P-based nanothickness bioceramic coated untreated implants (untreated nanotite implant), alumina-blasted/acid-etched titanium implants (AB/AE implant) and hydroxyapatite plasma-sprayed implants (PSHA Implant). Balb/c 3T3 fibroblasts were used to asses the cytocompatibility of implant materials according to ISO-10993-5 protocols. Osteablasts from Balb/c femurs seeded onto different implant surfaces showed the effect of surface topography and chemistry on cell adhesion. The results showed that all implants were not cytotoxic and that PSHA and AB/AE nanotite implants favored osteoblasts adhesion.

The objective of this study was to physico/chemically characterize and determine the corrosion resistance of a Calcium-Phosphate (Ca-P) based bioceramic thin coating processed by a sputtering process on titanium alloy (Ti-6Al-4V). The samples utilized in this study were uncoated and coated disks of 10 mm diameter by 3 mm thickness. The coating was characterized by SEM, XPS + ion beam milling (IBM), thin-film mode XRD, and atomic force microscope (AFM) (n = 3). Coated and uncoated Ti-6Al-4V disk surfaces were tested in Phosphate Buffered Saline (PBS) at 25 degrees C through an area of 0.79 cm(2). A three-electrode cell set-up was used with a saturated calomel electrode (SCE) and a platinum wire as reference and counter electrodes. After 3, 17, and 25 days of immersion, electrochemical impedance spectroscopy (EIS) experiments were performed (n = 3). The EIS tests were carried out in potentiostatic mode at the open circuit potential (OCP). The frequency range considered was from 100 kHz to 10 mHz, using 10 mV root mean square as the amplitude of the perturbation signal. A potentiodynamic polarization scan using a frequency response analyzer potentiostat, was acquired following 3 days of immersion in PBS. The potentiodynamic polarization scans (n = 3) were carried out with a scan rate of 1 mV/s ranging from -0.8V(SCE) to 3.0V(SCE). Results: The physico/chemical characterization showed an amorphous Ca- and P-based coating of ~400-700 nm thickness with Ca-P nanometer size particles embedded in a Ca-P matrix. The Bode phase angle diagrams showed highly capacitive results at low and medium frequencies for both surfaces tested. The polarization curves showed low current densities at the corrosion potential (E (corr)), in the order of 10(-8)A/cm(2), typical of passive materials with protective surface films. Coated sample current densities were comparable to the uncoated samples. Conclusion: Coated and uncoated samples were stable in the test solution with a protective film maintained throughout the 25 day immersion test period

BACKGROUND: Patients seeking elective aesthetic surgery often use herbal medications and/or antidepressants. As the popularity of these medications grows, the plastic surgeon must become familiar with these drugs and their potentially harmful effects during the perioperative period. METHODS: The authors performed a PubMed search to identify commonly used herbs and antidepressants and their effects on patients during elective cosmetic surgery. RESULTS: Case series, studies, and reviews for 29 of the most common herbs and antidepressant medications were obtained from this search. On the basis of the existing data, the authors established recommendations for the management of these medications before elective cosmetic surgery. CONCLUSIONS: Most commonly used herbs and antidepressant medications have potentially deleterious effects on the patient during surgery, ranging from increased risk of bleeding to fatal interactions. The plastic surgeon must be familiar with these drugs to manage these patients appropriately

PURPOSE: Mechanical analyses of idealized crown-cement-tooth systems through finite element analysis (FEA) has provided valuable insight concerning design parameters and materials that favor lower stress patterns. However, little information regarding variation of basic preparation guidelines in stress distribution has been available. The primary objective of this study was to evaluate maximum principal stresses on a molar crown veneer plus core system natural tooth configuration preparation with variations in the ratio of proximal axial length (PAL) to buccal axial length (BAL) as well as loading condition and position. MATERIALS AND METHODS: Three-dimensional models comprising a crown veneer (porcelain), crown core (zirconia), cement layer, and tooth preparation (4.2 mm BAL with PAL reductions of 0.8 mm, 1.0 mm, and 1.2 mm) yielding BAL:PAL ratios of 1.23, 1.31, and 1.4 were designed by computer software (Pro/Engineering). The models were imported into an FEA software (Pro/Mechanica), with all degrees of freedom constrained at the root surface of the tooth preparation. Each tooth preparation crown configuration was evaluated under a vertical (axial) 200 N load, and under a combined vertical 200 N and horizontal (buccally) 100 N load applied at different positions from the central fossa to the cusp tip. Maximum principal stress (MPS) was determined for the crown core for each crown BAL:PAL ratio, loading condition, and position. RESULTS: Under both vertical and combined loading conditions, the highest MPSs were located at the occlusal region and in the occlusogingival region of the ceramic core. MPS values increased in the proximal region as the BAL:PAL ratio increased. Combined loading resulted in a general increase in MPS compared to vertical loading. CONCLUSION: Increasing the BAL:PAL ratio (reducing the proximal axial length of the preparation) acted as a stress concentrator at regions near the crown margins, suggesting this area may be vulnerable to damage from fit adjustment as well as during function. Such increases in stress concentration should be considered in clinical scenarios, especially when inherent flaws are present in the material, since extensive high-magnitude tensile stress fields have been noted under all loading conditions

A 29-year-old woman with Freeman-Sheldon syndrome had a history of recurrent frontal sinus infections for which she underwent a 1-stage frontal sinus obliteration and cranioplasty using a free fibula osteocutaneous flap. This case is unique in that a free fibula flap had never been used to obliterate the frontal sinus in a patient with Freeman-Sheldon syndrome, nor had it been harvested from a limb with a clubfoot.

BACKGROUND: This study was designed to evaluate the efficacy of direct corneal neurotization using contralateral supraorbital and supratrochlear nerves in patients with unilateral facial palsy and corneal anesthesia. A novel surgical procedure in which these donor nerve branches are inserted at the contralateral anesthetic corneal limbus for sensory neurotization is described. METHODS: The charts of six patients were reviewed thoroughly to evaluate changes in corneal sensibility following surgery for direct corneal neurotization. Visual acuity, blink reflex, donor deficit, synesthesia, long-term corneal health, and several psychosocial measures and overall patient satisfaction with the procedure are reported. RESULTS: Six patients with an average denervation time of 7.00 +/- 8.56 years before surgery were followed for an average period of 16.3 +/- 2.42 years. All six eyes showed improvement of corneal sensibility, visual acuity, and corneal health and remained free of ulcers or other signs of advancing neurotropic keratopathy. Average corneal sensibility improved from 2.00 +/- 4.47 mm before surgery to 278.00 +/- 226.00 mm following corneal neurotization (p < 0.016). CONCLUSIONS: Direct neurotization of the cornea using the contralateral supraorbital and supratrochlear branches of the ophthalmic division of the trigeminal nerve appears to be an effective method of restoring the corneal sensibility in patients with unilateral facial palsy and anesthetic cornea. This technique preserves ocular anatomy and cosmesis and restores function by improving corneal health and visual acuity