Hepatitis viruses A, B, C, D, E and G: implications for dental personnel

The programed death-1/programed death ligand-1 axis and its potential as a therapeutic target for virus-associated tumours

As an important and serious condition impacting human health, the diagnosis, and treatment of tumours is clinically vital because tumour cell immune escape sustains tumour development. Programed death ligand-1 (PD-L1) on tumour cell surfaces binds to the programed death-1 (PD-1), inhibits T cell activation, and induces apoptosis, and incapacitates cells. This allows tumour cells to evade recognition and clearance by the immune system, thereby permitting tumour occurrence, and development and poor prognosis outcomes in patients with tumours. Currently, anti-PD-1/PD-L1 immunotherapy has become pivotal in tumour treatment. Pathogens, especially viruses, are important factors which induce many tumours. In this article, we examine associations between Epstein-Barr virus, human papilloma virus, hepatitis B virus, hepatitis C virus, and human immunodeficiency virus type 1-related tumours and PD-1/PD-L1 axis.

Liver cancer prediction in a viral hepatitis cohort: A deep learning approach

Viral hepatitis is the primary cause of liver diseases, among which liver cancer is the leading cause of death from cancer. However, this cancer is often diagnosed in the later stages, which makes treatment difficult or even impossible. This study applied deep learning (DL) models for the early prediction of liver cancer in a hepatitis cohort. In this study, we surveyed 1 million random samples from the National Health Insurance Research Database (NHIRD) to analyze viral hepatitis patients from 2002 to 2010. Then, we used DL models to predict liver cancer cases based on the history of diseases of the hepatitis cohort. Our results revealed the annual prevalence of hepatitis in Taiwan increased from 2002 to 2010, with an average annual percentage change (AAPC) of 5.8% (95% CI: 4.2-7.4). However, young people (aged 16-30 years) exhibited a decreasing trend, with an AAPC of -5.6 (95% CI: -8.1 to -2.9). The results of applying DL models showed that the convolution neural network (CNN) model yielded the best performance in terms of predicting liver cancer cases, with an accuracy of 0.980 (AUC: 0.886). In conclusion, this study showed an increasing trend in the annual prevalence of hepatitis, but a decreasing trend in young people from 2002 to 2010 in Taiwan. The CNN model may be applied to predict liver cancer in a hepatitis cohort with high accuracy.

Endodontics in Systemically Compromised Patients

A substantial number of people in today’s world are elderly and as the incidence of a number of pathologies increases with age, it is predicted to produce millions of individuals with systemic medical conditions that can affect oral health and subsequent dental treatment. The dental management of these medically compromised patients can be sometimes problematic in terms of oral complications, dental therapy, and emergency care. One of the challenges faced by dental specialists today is the assessment and management of these patients. As mentioned in detail in Chap. 12, geriatric patients are much more likely to be at least partially dentulous having a complex medical history and the use of multiple medications.

Hepatitis B vaccination and associated oral manifestations: a non-systematic review of literature and case reports

Hepatitis B vaccine has been administered in children and adults routinely to reduce the incidence of the disease. Even though, hepatitis B vaccine is considered as highly safe, some adverse reactions have been reported. A literature search was carried out in PubMed, accessed via the National Library of Medicine PubMed interface, searching used the following keywords: Hepatitis B vaccine and complications from 1980 to 2014. A total of 1147 articles were obtained out of which articles, which discuss the complications occurring orally or occurring elsewhere in the body, which have the potential to manifest orally after hepatitis B vaccination were selected. A total of 82 articles were identified which included 58 case series or case reports, 15 review articles, 4 cross sectional studies, 3 prospective cohort studies, one retrospective cohort study and a case control study. After reviewing the literature, we observed that complications seen after Hepatitis B vaccination are sudden infant death syndrome, multiple sclerosis, chronic fatigue syndrome, idiopathic thrombocytopenic purpura, vasculititis optic neuritis, anaphylaxis, systemic lupus erytymatosus, lichen planus and neuro-muscular disorder. Of these complications, some are manifested orally or have the potential to manifest orally. Although, most of the complications are self-limiting, some are very serious conditions, which require hospitalization with immediate medical attention.

Hepatitis B vaccination and associated factors among dentists

OBJECTIVE

We calculated the prevalence and studied the factors associated with hepatitis B vaccination. Reasons for non-vaccination among dentists were investigated.

METHODS

A cross-sectional study was performed in Montes Claros, Minas Gerais, from 2007 to 2008, to assess hepatitis B vaccination among practicing dental surgeons. Variables were evaluated using a previously tested structured questionnaire. Data underwent descriptive analysis. Non-conditional logistic regression was used to determine the variables associated with hepatitis B vaccination (p < 0.05).

RESULTS

There were 333 subjects eligible for the study, 297 (89.2%) participated, and 283 answered the question about vaccination; of these, 258 (91.2%) completed the three-dose schedule vaccination and 25 (8.8%) were not vaccinated or did not complete the vaccination schedule. Lack of information (48%) was stated as the main reason for not being vaccinated. Variables associated with vaccination were: tobacco use (OR = 2.50; IC95% = 1.22-7.13), alcohol consumption (OR = 2.99; IC95% = 1.16-7.74), satisfaction with the profession (OR = 4.62; IC95% = 1.50-8.25) and knowledge on the post-exposure management protocol (OR = 4.28; IC95% = 1.63-9.26).

CONCLUSIONS

We found a high prevalence of complete vaccination among dentists in Montes Claros. It is higher among professionals who do not use tobacco and alcohol, are more satisfied with their profession and know the protocol after occupational exposure. The study suggests that the lack of information is the main reason for not being vaccinated.

Oral fluid and hepatitis A, B and C: a literature review

BACKGROUND AND AIMS

Viral hepatitis is a significant global health problem that, depending upon the virus, affects individuals of the developing and/or developed world. In recent years, there has been renewed interest in whether oral fluids can be considered as a source of viral hepatitis transmission and whether oral fluid, in particular, whole saliva, may be a useful source for viral detection as part of the diagnosis and monitoring of viral hepatitis. The aim of this article was to review current data concerning the possible carriage of the hepatitis A, B and C viruses within saliva and gingival crevicular fluid. Such knowledge will indicate if (i) oral fluid is a possible source of infection and (ii) whether oral fluid can be used for diagnosis and monitoring of viral hepatitis.

DATA AND SOURCES

A literature search was conducted using PubMed (Medline), EMBASE/Excerpta medica, the Cochrane database and Scopus. The results were limited to published material after 2000. Relevant material was evaluated and reviewed.

CONCLUSION

There is some evidence that hepatitis viruses A, B and C are present in oral fluids, particularly whole saliva and gingival crevicular fluid and may thus be possible sources of viral detection in clinical diagnosis and monitoring. However, the data are inconsistent and warrant the need for well-planned longitudinal studies to explore the precise frequency of oral carriage of such viruses and to determine the virological and host factors that may influence the oral presence of hepatitis A, B and C viruses.

Hepatitis B virus infection in dentistry: a forgotten topic

More than two billion people have been infected with hepatitis B virus (HBV). Globally, 350-400 million suffer from chronic HBV infection. It is postulated that dentists and dental staff are infected and transmit the virus to their patients more than any other occupation. The aim of this article is to review the HBV incidence in dental society, the points of view of dentists and their patients regarding transmission of the virus during dental procedures, the occurrence of HBV outbreaks in dental clinics and the importance of methods of preventing HBV infection in dentistry.

Comparing dental students' knowledge of and attitudes toward hepatitis B virus-, hepatitis C virus-, and HIV-infected patients in Taiwan

This study investigated and compared Taiwanese dental students' knowledge of hepatitis B virus (HBV), hepatitis C virus (HCV), and HIV infection, attitudes toward infected patients, and important factors associated with the willingness to treat infected patients. In 2001, a self-administered questionnaire survey was conducted on all 1930 dental students enrolled from seven dental schools in Taiwan, with a response rate of 54.4%. Multiple logistic regression analysis was applied to assess the relationship between multiple factors and willingness to treat. Multivariate analysis was used to compare knowledge levels and the willingness. Of the respondents, 80%, 75%, and 49% were willing to treat HBV-, HCV-, and HIV-infected patients, respectively, and differences among the percentages were statistically significant. Students were less knowledgeable about HCV infection compared to HBV and HIV infection. Factors significantly associated with willingness to treat HBV- or HCV-infected patients were: feeling morally responsible and being able to treat infected patients safely. Those feeling morally responsible (odds ratio [OR] = 33.0, 95% confidence interval [CI] = 15.2, 71.8) and those being able to treat infected patients safely (OR = 4.1, 95% CI = 1.7, 9.9) were more willing to treat HIV patients. Taiwanese dental students were more willing to treat HBV- and HCV-infected patients than to treat HIV-infected patients.

Immunizations and oral health care providers

Two very successful approaches aimed at preventing infectious diseases acquired in the dental office have introduced more vigilant infection control and barrier techniques as well as the use of specific immunizations. Special consideration is given to the subgroup of dental professionals at increased risk for common diseases that may prevail because of the location and demographics of their practices. A brief review of the basic principles of immunology and immunization is covered as well as immunizations and the medically compromised oral health care worker, the medically compromised patient, new vaccines that may be in the offing, and the future role of immunization for dentists.

Advances in the diagnosis and management of human viral hepatitis

This article presents a comprehensive review of viral hepatitis types A through G and TTV. The information that is provided includes the definition, causes, signs and symptoms, diagnosis, pathogenesis, and acute and chronic forms of hepatitis. The modes of transmission, risk groups, morbidity and mortality, epidemiology, and treatment modalities are also presented. The primary objective for this extensive review is to provide dental health care workers with the most current information on the subject, which will allow them to identify the patients who will potentially have complications as the result of invasive dental treatment. By using this information, dental health care workers can be assured that they are practicing "state-of-the-art dentistry" while ensuring the health of their patients, staff, and families.