Use of intravenous sedation is increasing in the management of dental patients in consideration of accompanying diseases and patient demand for comfort and safety. We surveyed choice of sedative agent and dosage on the basis of accompanying diseases or conditions in patients receiving treatment at the Department of Dental Anesthesiology, Tokyo Dental College Chiba Hospital between 2010 and 2011. A total of 5,256 patients were reviewed and divided into the following categories: 1) medically compromised patients (MC); 2) minor oral surgery (OS); 3) cerebral palsy (CP); 4) mental retardation (MR); 5) mental disorder (MD); and 6) dental phobia with/without gag reflex. The investigated variables were sex, age, weight, duration of sedation, and dosage of agent. Dosage of midazolam (M), M plus propofol (MP), and P alone was investigated. A total of 2,336 patients were managed by intravenous sedation during the study period. The combination of MP was used in approximately 63–79% of patients in all categories, except MC. Midazolam was used in approximately 47% in the MC group. Propofol was used in approximately 32% of patients in the MR group. Other agents (minor tranquilizers, analgesics, and so on) were used in approximately 12% in the OS group. The dose of M was approximately 0.05–0.06 mg/kg. When MP was administered, the dose of M showed no difference among groups. The dose of P, however, tended to be lower in the MC and CP groups than in the other groups. These results suggest that MP is chosen for intravenous sedation in most types of dental treatment.