[Influence of risk factor "hot foods over 37 degrees Celsius" on oral flora and the pathogenesis of gingivitis and periodontitis].

Austrian law prescribes that hot food and beverages must be served at a minimum temperature of 75 degrees C. Within a group of 50 volunteers, we studied hot food at a temperature higher than 37 degrees C as a risk factor for the pathogenesis of gingivitis and periodontitis. In the first part of the investigation the effects of heat on bacterial growth in the mouth were evaluated. Bacterial growth was significantly reduced after drinking hot tea (70 degrees C) (p < 0.001). The ability of the volunteers to estimate the temperature of a direct heat stimulus in the mouth was tested in the second part of the study. 82% of the volunteers underestimated the temperature of tea (70 degrees C) by about 15 degrees C. In the third part of the study the periodontal state of the volunteers was determined by index measurements. Moreover, eating behaviour was assessed by a questionnaire. No statistically significant correlation between eating behaviour (hot/cold) and periodontal inflammation was found.