The role of cytomegalovirus infection in the pathogenesis of periodontal diseases.

The main characteristic ofperiodontal disease is chronic inflammation that leads to progressive destruction of the connective tissues and bone with subsequent tooth mobility and finally tooth loss. Traditionally, the pathogenesis of periodontitis was based on the infection caused by bacteria that colonize tooth surface and gingival sulcus. Accumulated evidence show that host response factors such as inflammatory reaction and activation of the innate immune system are critical to the pathogenesis of periodontal disease. Periodontal disease has been widely recognized as a chronic disease but the nature of chronicity remains unclear. The question is whether periodontal disease is a continuous process or consists of episodes of exacerbations and remissions. Maybe cytomegalovirus infection of the periodontium, depending on the latent or active phase of infection, can partly explain the episodic progressive nature of periodontal disease. Cytomegalovirus infection impairs periodontal defense and permits overgrowth of periodontopathogenic bacteria. Owing to advances in new technologies, experimental evidence show the influence and interrelatedness of genomic, epigenetic, proteomic and metabolic factors in the pathogenesis of periodontal disease. Data on the pathogenesis of periodontal disease are reviewed.