Imran Farooq, Abdul Khabeer, Saqib Ali, Baal Jandan.
Effect of various predisposing factors on host defence mechanisms triggering oral infections - a comprehensive review.
J Med Sci Jan ;27(4):370-5.

The oral cavity consists of normal micro-flora which is essential for a healthy mouth. In certain conditions, some of the micro-flora can act as opportunistic pathogens that can breach the host defence and invade deeper tissues to cause infection. Apart from microbial causes, there are many other diverse local and systemic predisposing factors that can also affect host defence mechanisms. In this review, host defence mechanisms have been described briefly and the predisposing factors that can affect an individual’s immunity; thus making them more prone towards an infection are also covered. The past 70 years of literature were searched on the “Google Scholar” search engine with the keywords “host defence mechanisms”, “immunity”, “predisposing factors affecting host defence mechanisms”, and “causes of oral infections”. Duplicate articles, conference abstracts, and all the articles/books published in languages other than English were excluded. The review concluded that many oral infections are related to predisposing factors and the initiation and progression of infections are dependent on the equilibrium between host defence mechanisms and these factors. Whenever this balance is disturbed, infections can ensue. Maintenance of good oral hygiene and avoidance of predisposing factors is, therefore the key to avoiding many oral infections.

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