This article gives a brief overview of the causes of tooth loss. Caries is still the most prominent reason for tooth loss. In patients over 40 years, periodontal reasons become more prevalent. However, also in this age category caries is the main reason. In young individuals, missing teeth are most frequently associated with agenesia or trauma. Iatrogenic damage is considered to be a casuistic cause of tooth loss. Nevertheless, some specific areas, such as in the combined treatment 'endodontic treatment--post and core--crown', can be distinguished in which tooth loss is more frequently seen.