There was no documented information about the subject of this survey
   in the country. Regarding the importance of these lesions and their
   pathologic changes and considering this epidemiologic survey as  a base
   for future analytical researches , the survey seemed to be justified.

          A cross - sectional descriptive study was designed and with a cluster –
   random sampling the 350 patients selected in five zone of Hamadan, who
   were interviewed, and clinically examined at their homes in 1997.   

          78.8% of the surveyed patients had at least one denture induced soft
   tissue lesion. The most common lesion was inflammatory fibrous hyperplsia
   (26.8%)and Angular chellitis had the least prevalence(2.5%). Other soft tissue
   changes lied between these two rates.

          The denture induced soft tissue lesions had considerably more
   prevalence than any reports up to the time of survey which need more
   investigation.