France has a system of public coverage that guarantees low-income earners full payment of basic dental health costs. In spite of this coverage and major needs for care, deprived populations have lower access to dental care. The aim of this qualitative study was to explore dentists' experience with low-income patients benefiting from the French universal healthcare coverage system. This study is based on 17 one-on-one semistructured interviews carried out with French private dentists. Dentists distinguished two categories of low-income patients: 'good patients', described as being regular attenders; and 'bad patients', whose main characteristic is irregular attendance. Dentists explained that they have difficulties in dealing with patients who do not keep their appointments. First, dentists feel that they fail in conducting their mission of being a care provider (therapeutic failure). The absence of the patient is also seen as a lack of recognition (relationship failure). Furthermore, dentists do not earn money when patients miss their appointments (financial failure). In this context, many dentists feel discouraged and powerless (personal failure). Moreover, dentists do not understand why patients renounce the dental-care opportunities offered under the system of public coverage (failure of the system). Dentists who repeatedly experience failures related to irregular attendance tend to adopt exclusion strategies.