Surveys of adult dental health in recent years have shown that more than one third of the United Kingdom population over the age of sixteen years is edentulous. In spite of this, surprisingly little research work has been carried out into the nature of oral mucosa in the edentulous mouth. The initial part of this work was to devise a method for the quantitative evaluation of oral mucosa. This was achieved by modifying the techniques of stereology described by Warnakulasuriya (1976). In addition, descriptive analysis was carried out on the stratum corneum to assess the type and degree of keratinisation. These techniques were used to evaluate the differences between mucosa on the crest of the ridge in the maxillary first molar and mandibular anterior regions in post-mortem material. Intact edentulous palates were obtained post-mortem and cross-sections were prepared in the first molar region. These enabled an assessment to be made of the regional variations in the tissues across the palate from the surface layer to the periosteum. In order to determine the effects of complete dentures on oral mucosa, it is necessary to have detailed information on the structure of normal oral mucosa. Quantitative and descriptive analyses were therefore undertaken on a number of patients to provide baseline data. Having established this information, the study was extended to include patients who had been wearing dentures for a number of years and whose oral mucosa was clinically normal. These results enabled conclusions to be drawn on the effects of complete dentures on oral mucosa. Throughout this work the effects of the age and the sex of the individuals on the mucosa were evaluated. In addition, in the clinical studies, the influence of the number of hours of denture-wearing per day, the length of denture experience and the smoking habits of the individuals were assessed
