Faculty Bibliography

AIM: There is little information considering the framework association between cast clasps and attachments. The aim of this study was to evaluate the retention strength of frameworks match circumferential clasps and extra resilient attachment cast in three different alloys (cobalt-chromium, nickel-chromium titanium and commercially pure titanium), using two undercut (0.25 and 0.75 mm) and considering different period of time (0, 1/2, 1, 2, 3, 4 and 5 years). METHODS: Using two metallic matrices, representing a partially edentulous mandibular right hemiarch with the first molar crown, canine root and without premolars, 60 frameworks were fabricated. Three groups (n = 20) of each metal were cast and each group was divided into two subgroups (n = 10), corresponding the molar undercut of 0.25 mm and 0.75 mm. The nylon male was positioned at the matrix and attached to the acrylic resin of the prosthetic base. The samples were subjected to an insertion and removal test under artificial saliva environment. RESULTS: The data were analyzed and compared with ANOVAs and Tukey's test at 95% of probability. The groups cast in cobaltchromium and nickel-chromium-titanium had the highest mean retention strength (5.58 N and 6.36 N respectively) without significant difference between them, but statistically different from the group cast in commercially pure titanium, which had the lowest mean retention strength in all the periods (3.46 N). The association frameworks using nickel-chromium- titanium and cobalt-chromium could be used with 0.25 mm and 0.75 mm of undercut, but the titanium samples seems to decrease the retention strength, mainly in the 0.75 mm undercut. The circumferential clasps cast in commercially pure titanium used in 0.75 mm undercuts have a potential risk of fractures, especially after the 2nd year of use. CONCLUSION: This in vitro study showed that the framework association between cast clasp and an extra resilient attachment are suitable to the three metals evaluated, but strongly suggest extra care with commercially pure titanium in undercut of 0.75 mm. CLINICAL SIGNIFICANCE: Frameworks fabricated in Cp Ti tend to decrease in retentive strength over time and have a potential risk of fracture in less than 0.75 mm of undercut.

While acute tissue injury potently induces endogenous danger signal expression, the role of these molecules in chronic wound healing and lymphedema is undefined. The purpose of this study was to determine the spatial and temporal expression patterns of the endogenous danger signals high-mobility group box 1 (HMGB1) and heat shock protein (HSP)70 during wound healing and chronic lymphatic fluid stasis. In a surgical mouse tail model of tissue injury and lymphedema, HMGB1 and HSP70 expression occurred along a spatial gradient relative to the site of injury, with peak expression at the wound and greater than twofold reduced expression within 5 mm (P < 0.05). Expression primarily occurred in cells native to injured tissue. In particular, HMGB1 was highly expressed by lymphatic endothelial cells (>40% positivity; twofold increase in chronic inflammation, P < 0.001). We found similar findings using a peritoneal inflammation model. Interestingly, upregulation of HMGB1 (2.2-fold), HSP70 (1.4-fold), and nuclear factor (NF)-kappabeta activation persisted at least 6 wk postoperatively only in lymphedematous tissues. Similarly, we found upregulation of endogenous danger signals in soft tissue of the arm after axillary lymphadenectomy in a mouse model and in matched biopsy samples obtained from patients with secondary lymphedema comparing normal to lymphedematous arms (2.4-fold increased HMGB1, 1.9-fold increased HSP70; P < 0.01). Finally, HMGB1 blockade significantly reduced inflammatory lymphangiogenesis within inflamed draining lymph nodes (35% reduction, P < 0.01). In conclusion, HMGB1 and HSP70 are expressed along spatial gradients and upregulated in chronic lymphatic fluid stasis. Furthermore, acute expression of endogenous danger signals may play a role in inflammatory lymphangiogenesis.

PURPOSE: Computer use, Internet access, and online searching for health information were assessed toward enhancing Internet use for health promotion. DESIGN: Cross-sectional random digit dial landline phone survey. SETTING: Eight zip codes that comprised Central Harlem/Hamilton Heights and East Harlem in New York City. SUBJECTS: Adults 18 years and older (N=646). MEASURES: Demographic characteristics, computer use, Internet access, and online searching for health information. ANALYSIS: Frequencies for categorical variables and means and standard deviations for continuous variables were calculated and compared with analogous findings reported in national surveys from similar time periods. RESULTS: Among Harlem adults, ever computer use and current Internet use were 77% and 52%, respectively. High-speed home Internet connections were somewhat lower for Harlem adults than for U.S. adults overall (43% vs. 68%). Current Internet users in Harlem were more likely to be younger, white vs. black or Hispanic, better educated, and in better self-reported health than non-current users (p<.01). Of those who reported searching online for health information, 74% sought information on medical problems and thought that information found on the Internet affected the way they eat (47%) or exercise (44%). CONCLUSIONS: Many Harlem adults currently use the Internet to search for health information. High-speed connections and culturally relevant materials may facilitate health information searching for underserved groups.

Contrary to a clinical aphorism that early head and neck cancer is painless, we show that patients who develop head and neck cancer experience significant pain at the time of initial diagnosis. We compared orofacial pain sensitivity in groups of patients with normal oral mucosa, oral precancer, and newly diagnosed oral cancer. The University of California San Francisco Oral Cancer Pain Questionnaire was administered to these patients at their initial visit, before being prescribed analgesics for pain and before any treatment. In contrast to those with biopsy-proven normal oral mucosa and oral precancer, only oral cancer patients reported significant levels of spontaneous pain and functional restriction from pain. Moreover, oral cancer patients experienced significantly higher function-related, rather than spontaneous, pain qualities. These findings suggest an important predictor for the transition from oral precancer to cancer may be the onset of orofacial pain that is exacerbated during function. Screening patients who have new-onset orofacial pain may lead to a diagnosis of early resectable head and neck cancer and may improve quality of life and survival for head and neck cancer patients. An important predictor for the transition from oral precancer to oral cancer may be the onset of orofacial pain that is exacerbated during function

BACKGROUND AND PURPOSE: Small oral cavity tumors are an imaging challenge. Intimate apposition of vestibular oral mucosa to the alveolar mucosa makes tumor assessment difficult. In CT imaging, the 'puffed cheek' method has been used to separate surfaces, though this is not feasible with long MR imaging sequences. We implemented placement of 2 x 2 inch (6.45 cm) gauze into the oral vestibule before the MR imaging examination, to determine whether this might improve tumor visualization. MATERIALS AND METHODS: MR imaging examinations of all T1 oral malignant tumors treated at University of California, San Francisco, by the Oral and Maxillofacial Department were reviewed by 2 neuroradiologists. Nine patients were included in the final analysis. Six patients were imaged by using a standard protocol. Three patients were imaged with gauze placement. The radiologists evaluated the MR images, assessing whether they could see the tumor and then fully delineate it and its thickness. RESULTS: Fisher exact analysis was performed on questions 1, 2, and 4 with the following results: P value = .048, Can you see the tumor? P value = .012, Can you fully delineate? P value of .012, How confident are you? MR imaging examinations with gauze clearly delineated the tumor with the tumor thickness measurable. MR imaging examinations without gauze did not clearly show the tumor or its thickness. Confidence of interpretation of the findings was also increased when gauze was used. CONCLUSIONS: A 2 x 2 inch (6.45 cm) rolled gauze in the oral vestibule significantly improved tumor localization and delineation at MR imaging. This technique is simple and provides superior preoperative imaging evaluation and treatment planning of small oral cavity tumors

BACKGROUND: Chemical modification of implant surface is typically associated with surface topographic alterations that may affect early osseointegration. This study investigates the effects of controlled surface alterations in early osseointegration in an animal model. METHODS: Five implant surfaces were evaluated: 1) alumina-blasting, 2) biologic blasting, 3) plasma, 4) microblasted resorbable blasting media (microblasted RBM), and 5) alumina-blasting/acid-etched (AB/AE). Surface topography was characterized by scanning electron microscopy and optical interferometry, and chemical assessment by x-ray photoelectron spectroscopy. The implants were placed in the radius of six dogs, remaining 2 and 4 weeks in vivo. After euthanization, specimens were torqued-to-interface failure and non-decalcified-processed for histomorphologic bone-implant contact, and bone area fraction-occupied evaluation. Statistical evaluation was performed by one-way analysis of variance (P <0.05) and post hoc testing by the Tukey test. RESULTS: The alumina-blasting surface presented the highest average surface roughness and mean root square of the surface values, the biologic blasting the lowest, and AB/AE an intermediate value. The remaining surfaces presented intermediate values between the biologic blasting and AB/AE. The x-ray photoelectron spectroscopy spectra revealed calcium and phosphorus for the biologic blasting and microblasted RBM surfaces, and the highest oxygen levels for the plasma, microblasted RBM, and AB/AE surfaces. Significantly higher torque was observed at 2 weeks for the microblasted RBM surface (P <0.04), but no differences existed between surfaces at 4 weeks (P >0.74). No significant differences in bone-implant contact and bone area fraction-occupied values were observed at 2 and 4 weeks. CONCLUSION: The five surfaces were osteoconductive and resulted in high degrees of osseointegration and biomechanical fixation.