Introduction to the major histocompatibility complex Cellular interactions are very important for the recognition and presentation of antigens to the immune system by antigen-presenting cells 13, 14. The primary components of these interactions are the T-cell antigen receptor (TCR) and the Major histocompatibility complex (MHC)/human leukocyte antigen (HLA) molecules. The major function of the TCR…
Read MoreIntroduction to humoral immunity Humoral immunity is the type of host defense that is mediated by antibodies, the products of B-cells. Antibodies are secreted into mucosal lumens, blood, and interstitial fluids, and combat microbes at all these sites. As already stated, B-cells are the source of antibodies, let us first understand the development and maturation…
Read MoreIntroduction to congenital immunodeficiency conditions Immunodeficiency can be broadly classified as primary or secondary. Primary immunodeficiency results from inherited immune disorders associated with genetic mutations, usually present at birth and diagnosed in childhood. On the other hand, secondary immunodeficiency is also referred to as acquired immunodeficiency that results from disease or environmental factors, such as…
Read MoreIntroduction to hypersensitivity Hypersensitivity is an exaggerated or inappropriate reaction harmful to the host. The first response sensitizes the immune system and subsequent contacts cause an allergic reaction. Hypersensitivity is of four types; Type I hypersensitivity – Anaphylactic shock. Type II hypersensitivity – Cytotoxic hypersensitivity Type III hypersensitivity – Immune complex hypersensitivity. TYPE IV hypersensitivity…
Read MoreIntroduction to immunity Immunity is defined as resistance to disease, specifically infectious disease. The immune system is the collection of cells, tissues, and molecules that functions to defend us against infectious microbes. The main function of the immune system is to prevent or limit infections. This defense function of the immune system is essential for…
Read MoreIntroduction to bone destruction in periodontitis Microbial etiology of periodontal diseases is well established, but the present data strongly suggest an equally important role of host immune response in the pathogenesis of periodontal diseases. The initial response to bacterial infection is a local inflammatory reaction that activates the innate immune system, causing the release of…
Read MoreIntroduction to the periodontal pocket The formation of a true periodontal pocket is the hallmark of periodontitis. It is characterized by the apical migration of the junctional epithelium from its normal position at the cementoenamel junction. Various investigators throughout history have tried to understand the exact mechanism of pocket formation. Historically, various theories of pocket…
Read MoreIntroduction to periodontal Pocket The periodontal pocket is a pathologically deepened gingival sulcus due to the apical migration of junctional epithelium. It may occur due to coronal movement of the gingival margin, apical displacement of epithelial attachment or a combination of the above. The coronal movement of the gingival margin (gingival enlargement) without the destruction…
Read MoreIntroduction to gingivitis It has been well established that diseases are initiated by oral bacteria perturbing epithelial cells, which trigger innate, inflammatory, and adaptive immune responses. These processes result in the destruction of the tissues surrounding and supporting the teeth and eventually result in tissue, bone, and, finally, tooth loss. Lipopolysaccharide (LPS) is a cell…
Read MoreIntroduction to the recent 2017 classification system Since the introduction of the World Workshop 1999 classification, tremendous research has been done in both basic and clinical fields in periodontics. With the evolution of new evidence, there was a need to re-define various periodontal and peri-implant diseases and conditions. With this intention, the American Academy of…
Read More