Infectious Diseases

One of the newest frontiers in oral medicine is understanding how bacteria and viruses interact with hosts. The human oral microbiome contains over 1000 bacterial and fungal species. The oral microbiome plays a very important role in oral and systemic health by inhibiting pathogen colonization, antagonizing pathogens by producing antimicrobial substances such as bacteriocin, and developing local and systemic immunity. This chapter focuses on atypical bacterial infections, such as sexually transmitted infections (STIs), actinomycosis, and tuberculosis. The four most common bacterial STIs are chlamydia, gonorrhea, syphilis, and trichomoniasis. The chapter discusses less common fungal infections, which can have oral manifestations. The majority of viral infections affecting the orofacial region are self-limiting in otherwise healthy individuals, while atypical presentations with systemic complications are more likely to occur in immunocompromised hosts. Hepatitis viruses cause serious liver damage and its consequences, especially susceptibility to bleeding and contraindications of certain drugs that depends upon the severity.