The aim of this study was to isolate, quantify, identify, and compare opportunistic microorganisms (Candida and Staphylococcus genera and Enterobacteriaceae/Pseudomonadaceae families) from prosthesis-fitting surfaces, the hard palate, and mouth rinses of individuals wearing removable maxillary prosthesis with (50) and without (50) lesions of denture stomatitis (DS). The strains were collected and identified using phenotypic, biochemical and molecular tests. The counts of microorganisms were significantly higher in the group of individuals with DS (P < 0.05). C. albicans was the most frequently isolated yeast species in both groups, following by C. tropicalis and C. glabrata. Six isolates were identified as C. dubliniensis. S. aureus and S. epidermidis were the most frequent Staphylococcus species in both groups. Klebsiella pneumoniae was the predominant species in both groups. The association between Candida spp. and bacteria isolated in this study with DS suggests that these microorganisms may play important roles in the establishment and persistence of this disease.

The aim of this study was to investigate a possible relation between oral squamous cell carcinoma (SCC), the presence of high-risk human papillomavirus (HR-HPV) DNA and p16 expression in young patients. Paraffin-embedded tumor blocks from 47 oral SCC of young ( 40-year old) patients were evaluated. The presence of HPV DNA in tumor specimens was analyzed by polymerase chain reaction (PCR) using GP51/GP61 generic primers (L1 region) followed by dot blot hybridization for HPV typing. When necessary, the HPV16 positivity was confirmed by PCR HPV16 E7-specific primers. Cases involving young patients were compared with 67 oral SCC from patients !50-year old (controls). Demographic and clinical data were collected to analyze patient outcomes. p16 ink4 expression was evaluated by immunostaining of tissue microarrays. HPV16 was detected in 22 (19.2%) cases; 15 (68.2%) young and 7 (31.8%) control patients, a statistically significant difference (p 5 0.01). In 1 (1.7%) young group specimen, HPV DNA 16 and 18 was detected. p16 expression was observed in 11 (25.6%) cases from the young group and in 11 (19.6%) controls (p 5 0.48). Association between HPV and p16 was verified, and it was statistically significant (p 5 0.002). The higher prevalence of high-risk HPV types, especially HPV16, may be a contributing factor to oral carcinogenesis in younger individuals.Oral squamous cell carcinoma (SCC) affects mainly men between the fifth and sixth decades of life 1 and is rare in young patients ( 40-year old); however, incidence in this age group has increased in several countries over the last two decades. 2,3 In older patients, the main risk factors are tobacco and alcohol consumption. 1 However, in younger patients, the role of these factors is uncertain due to the short time of exposure. 4,5 Some studies have reported that high-risk human papillomavirus (HR-HPV) infection might exert an important role in carcinogenesis in this group. 6-11 HR-HPVs, especially HPV16 and HPV18 are considered a major cause of certain human cancers; they are responsible for all cervical cancers and about 50% of other anogenital cancers. 12 In oral SCC, their prevalence and importance are controversial. [6][7][8][9][10][11][13][14][15][16][17] HPV infection occurs more frequently in young individuals than in older 7,18,19 and it is correlated to sexual behavior. 18,19 The HPV oncoproteins E6 and E7 stimulate cell proliferation by activating cyclins E and A and inactivating p53 and retinoblastoma (Rb) cell cycle proteins. The absence of functional pRb can upregulate p16 ink4 expression. 12 p16 ink4 expression has been used to determine the presence of biologically active HPV in head and neck (HN) SCC. 20 Reports suggest that tumors with p16 ink4 expression and HPV positivity show improved survival rates, 18,21,22 although consensus has yet to be achieved. 16 The aim of this study was to determine HR-HPV prevalence and investigate a possible relation between the presence of HR-HPV DNA, p16 expression and clinical outcomes in oral SCC of young patients ...

In both groups, amplification had no influence on prognosis. Protein overexpression was an indicator of worse DFS in both groups.