Emotional stress effects on immunity, gingivitis and periodontitis.

Gingivitis and periodontitis are thought to result from an imbalance between those oral microorganisms which normally colonize tooth surfaces in close contact with the gingival margin, and the nature and efficiency of the host response. The bacteria are the triggering agents, but host defence mechanisms within the gingival/periodontal tissues seem to be responsible for most of the tissue damage and for the outcome and progression of the diseases. It has recently been shown that emotional or psychological load (stress) may influence immune activities directly via nerve messenger substances (neurotransmitters and neuropeptides) and/or indirectly via neuroendocrine (hormone) substances. This review discusses how emotional stressors and nervous and neuroendocrine responses to psychological stressors may modulate the immune response to bacteria, and thus be expected to influence the progression and course of gingivitis and periodontitis.