This study investigated the effectiveness of subglottic irrigation (SI) with 100 mL of saline on reducing bacterial contamination in the subglottic space during oral surgery procedures without the use of throat packs. Subglottic lavage and irrigation were performed through the suction lumen located on specialized endotracheal tubes (ETTs) with capabilities of permitting evacuation from the subglottic space. Fifty-three patients who were scheduled for oral surgery procedures under general anesthesia while intubated with specialized ETTs at Kyushu Dental University Hospital were enrolled in this study. Subglottic irrigation was performed, and the sample fluid was collected through the ETT suction lumen for smear and culture bacterial examinations after 3 points in time: immediately after intubation, after completing the surgical procedure, and again after SI. Oral surgery without a throat pack significantly increased bacterial contamination in the subglottic lavage (p < .001), and SI decreased bacterial contamination (p < .001) similarly to levels found after tracheal intubation. Subglottic irrigation with 100 mL of saline was effective in reducing bacterial load in the subglottic space to levels similarly noted immediately after intubation for patients undergoing intraoral surgical procedures without the use of a throat pack.