The purpose of this study was to evaluate whether manipulation or position change of the head during dental procedures for handicapped patients (mentally retarded) using a reinforced laryngeal mask airway for ventilation would lead to air leak.All patients had a reinforced laryngeal mask airway inserted after induction of anesthesia; anesthesia was maintained with sevoflurane. Normal saline stained with methylene blue was instilled into the oral cavity of the patient. Then, the patient's laryngeal region was checked for blue staining with a fiberoptic bronchoscope. After dental treatment, the laryngeal region was checked again under fiberoptic bronchoscopy. The staining results were recorded and analyzed.In one of 51 patients (1.96%), the laryngeal region was stained blue after the flexible laryngeal mask airway was inserted. In ten of 51 (19.6%) patients, the laryngeal area was stained blue after the dental procedure. One of the ten patients who had a leak because the laryngeal mask was pulled out during the dental procedure. And in another one patient endotracheal tube was placed in lieu of laryngeal mask due to severe leakage. No oxygen desaturation below 90% occurred in all patients. No major complications such as fever or aspiration pneumonia were reported.The use of a reinforced laryngeal mask airway eliminates the complications due to endotracheal intubation and enhances the progress of the dental procedure. Although leakage may happen during dental manipulation, it usually does not raise serious problem. No serious complications such as aspiration were found in our cases. So a reinforced laryngeal mask airway may be considered to be another safe choice for maintenance of a patent airway in handicapped patients during dental procedures.