Objectives: We assessed the percentage of patients with hepatitis B virus (HBV), hepatitis C virus (HCV), or human immunodeficiency virus (HIV) infection diagnosed by preoperative screening, and estimated the cost of screening. Methods: We retrospectively analyzed elective surgical cases in our-maxillofacial surgery department between April 2012 and March 2015. We also compared the number of HBV+, HCV+, and HIV+ patients identified by preoperative screening to those identified through a preoperative interview and questionnaire. We also compared the prevalence of HBV and HCV infections by age, sex, and the eleven commonest dental diagnoses. Results: Of 4469 patients, 34 (0.76%) and 90 (2.01%) patients were seropositive for hepatitis B surface antigen (HBsAg) and HCV, respectively. Five (0.59%) of 845 patients exhibited HIV-1/2 antibody. The self-reported rates were as follows: HBV, 47.1% (16/34); HCV, 64.4% (58/90); and HIV, 60% (3/5). The odds ratio for HBsAg was not significant, irrespective of age. HCV antibody was more prevalent in patients with alveolar disorders and impacted teeth, after adjustment for age. The annual cost for screening was ¥12,750,000 (US $127,500 at an exchange rate of US $1 = ¥100). Conclusion: Given the high cost, low prevalence, and the real likelihood of seroconversion after testing, screening for HBV, HCV, and HIV infections in patients requiring dental and oral-maxillofacial surgery is impractical. Universal precautions, with post-exposure prophylaxis (PEP) as needed, remain the method of choice for minimizing risk to practitioners.