Corticosteroids are potent anti-inflammatory hormones that have been used effectively since the early 1950s to reduce swelling and pain following Dental surgery. Patients report a strong preference for corticosteroids when they have experienced surgery with and without this therapy. Nevertheless, because these hormones are potently immunosuppressant, there is a strong concern by clinicians that corticosteroids may delay healing, thereby increasing the risk of post-operative infection. For this reason, despite the known benefits, many oral surgeons do not administer corticosteroids to their patients. Surprisingly, the effects of corticosteroids on the healing of oral (mucosal) tissues have never been systematically examined and, hence, remain unclear. Recent evidence from our laboratory, using a well established oral wound model in humans, has found that reduced inflammation in the mouth relates to faster healing times. This strongly suggests that the anti- inflammatory properties of corticosteroids will not hinder, and may augment, the healing of oral tissues. This study will clarify this important point. Sixty adult volunteers (30 men, 30 women) will receive either corticosteroid, in a single intravenous dose common in oral surgery (125 mg methylprednisolone), or placebo. Subjects will then have three small wounds placed on the oral hard palate by a periodontist. A tissue biopsy will be obtained from one wound at 6h and one wound at 24h post-wounding to determine the degree of tissue inflammation at two time points. The third wound will be photographed daily until healed to determine healing rates. Finally, a biopsy of healed tissue will be obtained on Day 14 to assess scar formation. Approximately one month later, subjects will undergo the same procedure on the opposite side of the mouth and will receive the alternate drug treatment (drug order will be counter-balanced between subjects). This study design will enable us to directly assess the effects of corticosteroids on healing rates, inflammation and scar formation, using subjects as their own controls. The results of this study will have an immediate impact upon clinical Dentistry, by providing insight of how corticosteroid administration impacts upon oral tissue healing. If the rate of healing is unaffected or, as we predict, shortened following corticosteroid administration this strongly advocates corticosteroid administration in Dental surgeries. Conversely, if corticosteroids impair tissue healing then their use is put to question, especially for minor Dental procedures and in individuals at a higher risk of post-surgical infection. By better identifying when corticosteroid therapy is appropriate, these results will have a financial impact on health care by reducing direct costs (follow-up visits), indirect costs (loss of income) and intangible costs (pain and suffering) related to oral surgeries. This study will also provide a better understanding of the mechanisms which underlie oral tissue healing. Public Health Significance: These results will have an immediate impact upon clinical Dentistry, and possibly on cosmetic surgery, by providing insights of how corticosteroid administration impacts upon tissue healing. If the rate of healing is unaffected or shortened following corticosteroid administration, this strongly advocates corticosteroid administration in Dental surgeries; conversely, if corticosteroids impair tissue healing then their use is put to question, especially for minor Dental procedures and in individuals at a higher risk of post-surgical infection. By better identifying when, and for whom, corticosteroid therapy is appropriate, these results will impact health care expenses by reducing direct costs (follow-up visits), indirect costs (loss of income) and intangible costs (pain and suffering) related to oral surgeries. [unreadable] [unreadable] [unreadable]