Objective: This retrospective study investigated the incidence rate of accidental foreign body aspiration and ingestion according to patient sex and age and the dental department. This study was aimed to verify the risk factors for accidental foreign body aspiration and ingestion in dental practice. Methods: Accidental foreign body aspiration and ingestion cases were collected by searching the electronic health records and the Safety Report System of Yonsei University Dental Hospital from January 2011 to December 2017. The collected data comprised the patient age, sex, and medical condition, treatment procedure, and foreign objects that were accidentally aspirated or ingested. The incidence rate was calculated as the number of accidental foreign body aspirations and ingestions relative to the total number of patient visits, and differences according to the patient sex and age and the dental department were identified statistically. Results: There were 2 aspiration and 37 ingestion cases during the 7-year analysis period. The male-to-female incidence ratio was 22.7:8.1. The incidence rate trended upward with age and increased rapidly among those aged 80 or older. Seven of the 39 patients had intellectual disability, Lou Gehrig’s disease, dystonia, or oral and maxillofacial cancer. The incidence rate was the highest in the Predoctoral Student Clinic and the Department of Prosthodontics. The most frequently swallowed objects were fixed dental prostheses and dental implant components. Conclusion: The incidence rate of accidental foreign body aspiration and ingestion is higher in men than in women and the highest in patients aged 80 or older. The most frequently aspirated or ingested objects are fixed dental prostheses and dental implant components. Dental practitioners need to identify high-risk patients and apply various methods to prevent accidental foreign body aspiration and ingestion in dental clinics. Inexperienced dentists should be especially careful. Keywords: accidental foreign body aspiration and ingestion, incidence rate, dental treatment