The aim of the present study was to investigate the profile of surgical periodontal therapy performed at the Suidobashi Hospital of Tokyo Dental College, during the period of April 2010 through March 2011. A total of 112 periodontal surgeries in 69 patients (mean age: 51.4 years; 28 men and 41 women) were registered for the data analysis. The surgical interventions performed by 17 dentists comprised 79 cases of open flap debridement, 27 cases of periodontal regenerative therapy with enamel matrix derivative and 6 cases of periodontal plastic surgery. Eighty percent of the surgical sites were in the molar region and 41 cases had furcation involvement. In these patients, an improvement in oral hygiene status was observed prior to surgery: the mean plaque score of 45% at initial visit was significantly reduced to 31% after initial periodontal therapy (p<0.01). At sites that subsequently received open flap debridement or periodontal regenerative therapy, the mean probing depth and clinical attachment level after initial therapy was 6.4 mm and 7.6 mm, respectively. These values were significantly lower than those at initial visit (p<0.01). Lower prevalence of sites with positive bleeding on probing was observed after initial therapy. The initial periodontal therapy performed was considered to be effective in improving the periodontal condition of the sites prior to surgery. More effort, however, is indicated in improvement of patient oral hygiene status.