Phase 1 clinical trials frequently involve 18-26 year-old individuals. Subjects are monitored frequently for the occurrence of soft tissue lesions (e.g. aphthous lesions), tooth staining and other manifestations in the oral cavity. However, there is a paucity of data about these occurrences in a "normal" population, i.e. without any treatment or intervention. Fifty otherwise healthy 18-26 year-old students at Georgetown University were examined six times over the period of approximately one year. At each examination a) any soft tissue lesions were noted and photographed; b) teeth were photographed; and c) bleeding index determined. Data are presently being assimilated and various approaches to examination of the parameters involved in the study are being assessed.