microbiology

0 Tube – like structure

0 Includes: Gastrointestinal (GI) Tract or Alimentary Canal – mainly the mouth, pharynx(throat), esophagus(food tube leading to stomach), stomach and the small and large intestines. Also includes accessory structures such as teeth and tongue.

0 System for mastication, digestion and absorption.

9/23/2012 Alona Rose L. Jimenea 2

Microbial Diseases of Digestive System

Structure and Function of the Digestive System

0 Each milliliter of saliva contain millions of bacteria

0 Stomach and small intestine have few microorganisms; limited by hydrochloric acid produced by stomach

0 In contrast large intestine has enormous microbial populations; exceeding 1oo billion bacteria per gram feces



Normal Microbiota of the Digestive System



Dental Caries (tooth decay)

0 Mainly caused by accumulations of masses of microorganismsand their products; dental plaque – type of biofilm and areintimately involve in the formation of dental caries.



0 Characterized by inflammation and degeneration of structures that supportsthe teeth.

0 Cementum: specialized connective tissue that covers the roots of the teeth.0 Gingivitis: infection restricted to the gums.0 Periodontitis: gums are inflamed and bleed easily. [Prophyromonas]0 Acute necrotizing ulcerative gingivitis/ Vincent’s disease/Trench Mouth :

makes normal chewing difficult , foul breath [Prevotella intermedia]

Periodontal Disease










0 Mumps: swelling of parotid glands

0 Testes may become inflamed: orchitis.









Science

microbiology