AntimicrobianosProfi laxis antimicrobiana de corta duración versus profi laxis antimicrobiana de larga duración en cirugía maxilofacial mayor limpia-contaminada. Un estudio de cohorte Julio Villanueva M., Ignacio Araya C. y Nicolás Yanine M.Short-term antibiotic prophylaxis versus long-term antibiotic prophylaxis in major clean-contaminated maxillofacial surgery.Introduction: There is no consensus on the most appropriate duration of antimicrobial prophylaxis (single or multiple dose) in clean-contaminated maxillofacial surgery. Objective: To determine whether short-term antimicrobial prophylaxis is effective compared to long-term antimicrobial prophylaxis in preventing surgical site infection in clean-contaminated maxillofacial surgery. Patients and Methods: The cohort study included 527 patients. We compared the incidence of surgical site infection in two groups. One group received short-term antibiotic prophylaxis (single dose) and the other group, long-term antimicrobial prophylaxis (multiple dose). Results: The single dose group showed 5.7% of postoperative infections and the multiple-dose group, 5.9%, with an odds ratio of 0.96 (95% CI 0.44 to 2.10) p = 0.9214. Conclusion: No signifi cant differences were found between the infection incidences in the single dose antibiotic prophylaxis group compared with the use of multiple doses.