P53 Immunostaining As A Marker For Oral Cancer In Diagnostic Cytopathology-Preliminary Report

The expression of p53 in oral mucosal disorders is strongly associated with malignant disease. Smears from normal and malignant oral mucosa were investigated for the presence of p53 using CM1 polyclonal antibody against p53 protein. the expression of p53 in smears was compared with the expression of the marker in biopsies from these oral carcinomas. p53 was identified in eight smears from 12 biopsy positive oral cancers. It was not seen in smears from eight p53-negative oral cancers and 40 smears from normal oral mucosa. It is suggested that expression of p53 in smears from a clinically suspicious lesion may be of value in the diagnosis of oral carcinoma.     

The impact of liquid-based oral cytology on the diagnosis of oral squamous dysplasia and carcinoma

OBJECTIVE: Even though diagnostic oral exfoliative cytology is a useful, economical and practical tool in the diagnosis of oral dysplasia and carcinoma, it is not yet extensively used. The results of conventional exfoliative and liquid-based diagnostic cytology in oral potentially malignant lesions (PML) are herein reported and compared with the histological diagnosis. METHODS: Either conventional (89) or liquid-based (384) exfoliative cytology was used for the diagnosis of oral dysplasia/carcinoma in 473 subjects and the results were compared with scalpel biopsy histology. Cells were collected using a Cytobrush device for conventional smears and with a dermatological curette for the liquid-based cytology. The 'curette technique' also allowed for the collection of 'accidental' tissue fragments, utilized as microbiopsies. RESULTS: Histological diagnosis was squamous carcinoma in 96 of 473 cases, high-grade dysplasia (oral intraepithelial neoplasia two to three) in 24 and other lesions in 353 cases. The smears in the conventional cytology group were inadequate in 12.4%, with an 85.7% sensitivity and a 95.9% specificity. There were 8.8% of inadequate specimens in the liquid-based cytology group; sensitivity was 95.1% and specificity was 99.0%. CONCLUSIONS: Although conventional cytology is useful when diagnosing oral PML (better sensitivity and predictive positive value if compared with the cervical smear test with similar specificity) and can improve the accuracy of histological diagnosis, liquid-based cytology gives better results, as it not only enhances both sensitivity and specificity, but also provides material for further investigation (AgNORs, DNA, microbiopsies, etc.).     

Inhibitory effect of oral Lactobacillus against oral pathogens

Aims: To determine the inhibitory effect of oral Lactobacillus against putative oral pathogens. Methods and Results: Total 357 strains comprising 10 species of oral Lactobacillus, Lactobacillus fermentum (195), Lactobacillus salivarius (53), Lactobacillus casei (20), Lactobacillus gasseri (18), Lactobacillus rhamnosus (14), Lactobacillus paracasei (12), Lactobacillus mucosae (12), Lactobacillus oris (12), Lactobacillus plantarum (11) and Lactobacillus vaginalis (10) were used as producer strains. Inhibitory effect against a panel of indicators, periodontitis‐ and caries‐related pathogens, was assessed. Most oral Lactobacillus was able to inhibit the growth of both periodontitis‐ and caries‐related pathogens. The strongest inhibitory activity was associated with Lact. paracasei, Lact. plantarum, Lact. rhamnosus, Lact. casei and Lact. salivarius. Lactobacillus SD1–SD6, representing the six species with the strong inhibitory effect, inhibited growth of Streptococcus mutans ATCC 25175 in the biofilm model. Also, it was demonstrated that growth of Strep. mutans was inhibited in a mixture with Lact. paracasei SD1. The inhibition was enhanced in acidic condition and 5% glucose. Conclusions: The results have shown that oral Lactobacillus SD1–SD6 showed a strong inhibitory effect against Strep. mutans and Streptococcus sobrinus, as well as, Gram‐negative periodontal pathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. Significance and Impact of the Study: The results indicated that Lactobacillus may be of benefit as probiotics for the prevention of oral diseases.     

A review of the effectiveness of oral health promotion activities among elderly people

Objectives: This study aimed to review the effectiveness of oral health promotion studies conducted among elderly people between 1997 and 2007. Methods: Four electronic databases were searched and papers were rated for level of evidence and scientific quality. Key findings of the papers were summarised. Results: Thirteen thousand nine hundred and four papers were retrieved and 17 studies (18 papers) met the criteria for the review: 13 were randomised controlled studies, three were quasi‐experimental studies and one was a pre‐/post‐single group intervention study. According to the Levels of Evidence, 11 studies could be categorised as 1b and six studies could be categorised as 2b. The quality of the evidence of the 17 studies ranged from 12 to 19; 13 of the studies had a score of 15 or above; four of the studies ranged from 12 to 14. Evidence from oral health promotion activities aimed at preventing caries, improving periodontal health and altering oral health behaviours were reviewed. The use of fluoride, antimicrobial agents and health‐care provider education has important roles within oral health promotion activities for elderly people. Studies have tended to be of short‐term duration and rely on surrogate outcome measures of oral health. Conclusion: In the last 10 years, increasing attention has been paid to oral health promotion activities among the elderly population and high quality evidence has emerged. However, there is a need for even higher‐quality research to provide more definitive guidelines on oral health promotion practices for elderly people.     

Human oral epithelial cell culture II. Keratin expression in fetal and adult gingival cells

Summary Epithelial cells from human fetal and adult gingiva were cultured in keratinocyte growth medium (KGM), a serum-free medium. The expression of keratin proteins in these cells was evaluated using immunohistochemistry and SDS-PAGE-immunoblot analysis and compared with expression in the tissue. Keratins 5, 6, 14, 16, and 19 were identified in cells cultured from both fetal and adult tissues. K19 was localized in basal cells of fetal oral tissue but was not seen in adult gingiva (except for scattered Merkel cells). K1 and K10 were expressed in tissue, but not in cultured cells. The keratin profiles of cultured epithelial cells from several adult donors were similar and were identical in cultures from primary through Passage 5. K13, a differentiation-specific keratin, was expressed in all suprabasal cells of fetal oral epithelium, but shows only spotty expression in adult gingival tissue. K13 was expressed in cultures of fetal cells, but very weakly or not at all in cultures of adult cells. K13 expression was greater in cultures grown with physiologic calcium concentrations (1.2 mM) than in those grown at 0.15 mM or less. Our findings are consistent with basal-like characters of these cells in 0.15 mM calcium growth conditions. Differentiation of fetal oral cells in culture to the suprabasal basal cell stage in 1.2 mM Ca²⁺ is shown by the expressionof K13. This work was supported by Biomedical Research grant RR05346, National Institutes of Health grant DE04660, University of Washington Graduate Fund and Hack Foundation Fund, Department of Periodontology, University of Washington.     

益生菌与口腔微生态调控的研究进展

口腔疾病的发生和发展与口腔微生物群落的失衡密切相关。益生菌是一类对人体健康有益的活的微生物,主要通过分泌抗菌物质、与致病菌竞争性定殖、调节毒力相关基因表达、调节宿主免疫反应、调节氧化应激反应、参与硝酸盐—亚硝酸盐—一氧化氮代谢循环通路、调整生物膜pH值等过程发挥其益生效能。研究发现,益生菌疗法能够降低龋齿的风险、改善牙周状况、提高口腔黏膜病的治疗效果,有望成为防治口腔疾病的潜在途径。本文就近年来益生菌与口腔微生态调控相关的研究情况做一综述。     

基于微流控的生物被膜研究进展及口腔微生态系统应用展望

口腔是人体最重要的微生物储藏库之一,这些微生物通常以生物被膜的形式稳定地黏附于口腔内粘膜及牙齿表面,在病理条件下则可以深入髓腔及牙槽骨内,成为龋病、根尖周炎、牙周病等常见口腔疾病的主要病因,甚至与许多全身性疾病密切相关.在人类口腔微生态系统中,微生物种类繁多,生物被膜的构成及相互作用关系复杂,目前对其认识还十分有限;此...     

Prevalence of soft tissue oral lesion in elderly and its relations with deleterious habits

doi: 10.1111/j.1741‐2358.2011.00618.x Prevalence of soft tissue oral lesion in elderly and its relations with deleterious habits Introduction: With ageing, the oral mucosa becomes more susceptible to external stimuli. Objective: To investigate the prevalence of soft tissue oral lesion in elderly and its relations with deleterious habits. Materials and methods: It was a quantitative research conducted at the dental clinic of UNIFOR, Fortaleza‐CE, in the period from 1998 to 2006. The sample consisted of all 756 records of the elderly, and the data were processed by SPSS 15.0 (SPSS, Inc., Chicago, IL, USA). Results: The majority (63.0) were women, age 60–92, mean age 67 ± 6. The most significant proportions were married (48.4%), retired (42.3%) and incomplete primary school (31.5%). It was found a prevalence of 18.3% of oral lesions, with the risk being 1.6 times higher (p = 0.030) among youngest (up to 65 years) and 1.7 times higher among smokers (p = 0.048). Although this risk is 1.6 times higher among those who drank alcohol, it was not statistically significant (p = 0.122). Conclusion: The elderly showed a high prevalence of oral lesion, being the youngest, the smokers and the alcohol consumers those most vulnerable to the emergence of these diseases. Dental services need to implement programs of elderly care and health education, essential to clarify the risks and their associations with oral diseases, aiming to promote health.