Localization and characterization of human papillomavirus-16 in oral squamous cell carcinoma.

OBJECTIVES: The role of Human papillomavirus (HPV) in the oral squamous cell carcinoma (OSCC) has not been completely elucidated. The purpose of the present study was to investigate the prevalence and localization of HPV-16 virus in OSCC and to correlate HPV-16 positivity and p16INK4A expression with the clinical and pathological features of OSCC. METHODS: The archives of Oral Pathology at the University of Florida, College of Dentistry were accessed for demographic, clinical, histopathological data, and slides of 114 OSCC patients. HPV-16 positivity of OSCC was evaluated by p16INK4A immunohistochemistry (IHC) and HPV-16 E6/E7mRNA by in situ hybridization (ISH). RESULTS: Out of 114 consecutive pathological slides of OSCC, 16 samples (14%) showed positivity for p16INK4A by IHC and 14 samples (12%) were positive for HPV-16 E6/E7mRNA ISH and the Positivity showed a significant correlation with the patients' age, alcohol consumption, and the degree of OSSC differentiation. The hard palate showed the highest positivity of p16INK4A IHC and HPV-16 mRNA ISH (38%, 36% respectively). CONCLUSION: HPV-16 is a significant factor in oral carcinogenesis. We recommend using p16INK4A as a surrogate marker for HPV detection in OSCC, which can be complemented by RNA ISH for the identification of HPV subtypes.

Biological effect of the nanocrystalline calcium sulfate bone graft in the periodontal regeneration.

BACKGROUND: The ultimate goal of tissue engineering is to reproduce functional alveolar∖Periodontal complex. This study aimed to asses micro- and nano-formulated crystalline calcium sulfate as possible treatment of intrabony defect utilizing an autologous Platelet rich fibrin scaffold. SUBJECTS: and Methods: An experimental prospective split mouth design using eight healthy mongrel dog's was conducted. After two months of extracting the first premolar, bilateral intrabony defects were created mesial to the mandibular second premolar. One side was grafted by nanocrystalline calcium sulfate, while, the opposite side was grafted with microcrystalline calcium sulfate graft. Dogs were randomly euthanized after one month (group I) and 3 months (group II). The primary outcomes were the histological changes of new bone formation in hematoxylin and eosin and Masson trichrome stains, while histomorphometric and radiographic analysis were the secondary outcome followed by statistical analysis (P value was set at .05). RESULTS: There was a significant increase in the percentage of bone formation in relation to defect height in nanocrystalline compared to microcrystalline form after one month and three months in both histological (p-values of <0.0001) and radiographic results (p-values of <0.0001). CONCLUSION: Nanocrystalline calcium sulfate presented a significant enhanced periodontal regeneration compared to the microcrystalline form.

Can mandibular lingual canals be used as a forensic fingerprint?

OBJECTIVES: This study aimed to identify whether the lingual canals of the mandible can be used as a unique fingerprint when dealing with forensic victim identification. MATERIALS AND METHODS: The study consisted of two parts; an observational part and an objective image analysis part. In the observational part a total of 100 in vivo high resolution CBCT datasets of human mandibles were included in the process of simulated matching of ante-mortem (AM) and post-mortem (PM) data. For the objective image analysis part 10 dry human mandibles were scanned with 2 different Cone Beam Computed tomography (CBCT) machines. In the observational part of the study trained observers attempted to correctly identify matching pairs of images taken from the same mandible out of a series of 100 mandibles. The aim was to simulate matching of the neurovascular structures on AM and PM mandibular midline images and determine the percentage of mandibles identified correctly. In the objective image analysis part, simulated matching was carried out using a specific CBCT dataset acquired to mimic a PM dataset and 10 datasets acquired from a different CBCT device which served as the source of potential AM cases. Comparison between AM and PM datasets resulted in the matching of the AM data and PM data obtained from the same mandible, leading to an assumed correct identification. RESULTS: The observational part of the study showed an average 95% correct identification of the mandibular midline neurovascular structures. Registration of mandibles resulted in perfect overlap of the same mandible from 2 different CBCT machine with an error distance equalling zero, while the registration of different mandibles deviated on average error distance 0.13 mm to 0.18 mm. CONCLUSION: The percentage of fit for the simulated AM and PM data of the same mandible was 100%. This finding together with the significant deviations noted for the non-matching cases, may have a potential role in forensic identification in the same way that fingerprints are recognised as being a unique identifying feature.

Allopurinol as a potential therapeutic agent for recurrent herpes labialis.

Recurrent herpes labialis (RHL) occurs in up to 40% of the population. Although the disease is usually self-limiting, patients seek treatment because of the significant pain and visibility of the lesion. Xanthine oxidase inhibitors (XOI) have been reported to have a potent antiviral effect against influenza-A virus. We examined the effect of the systemic xanthine oxidase inhibitor, allopurinol, on RHL duration of illness, severity of symptoms, number and frequency of recurrence during a 4-year follow up period in Egyptian patients. Duration of illness was shortened by about 25%, early disappearance of pain and other symptoms occurred. Also, aborted episodes were noticed when allopurinol was given just after beginning of common colds, at the prodromal stage of RHL or during severe stress conditions. Patients receiving 3 courses of treatment had markedly decreased recurrences during the follow up period. Ex vivo experiments to examine virus-induced plaque formation on Vero cells in the absence or presence of different concentrations of the drug could not prove any direct anti herpetic effect of the drug. However, allopurinol seems to be safe and effective in reducing duration of RHL and to abort lesion or prevent its appearance in treated patients even when they experience immunosuppressive conditions.