Background Frailty has been demonstrated to negatively influence dental service-use and oral self-care behavior of older people. The aim of this study was to explore how the type and level of frailty affect the dental service-use and oral self-care behavior of frail older people. Methods We conducted a qualitative study through 51 open interviews with elders of varying frailty in the East-Netherlands, and used a thematic analysis to code transcripts, discussions and reviews of the attributes and meaning of the themes to the point of consensus among the researchers. Results Three major themes and five sub-themes emerged from our analyses. The major themes indicate that frail elders: A) favor long-established oral hygiene routines to sustain a sense of self-worth; B) discontinue oral hygiene routines when burdened by severe health complaints, in particular chronic pain, low morale and low energy; and C) experience psychological and social barriers to oral health care when institutionalized. The subthemes associated with the discontinuation of oral care suggest that the elders accept more oral pain or discomfort because they: B1) lack belief in the results of dental visits and tooth cleaning; B2) trivialize oral health and oral care in the general context of their impaired health and old age; and B3) consciously use their sparse energy for priorities other than oral healthcare. Institutionalized elderly often discontinue oral care because of C1) disorientation and C2) inconveniencing social supports. Conclusion The level and type of frailty influences people’s perspectives on oral health and related behaviors. Frail elders associate oral hygiene with self-worth, but readily abandon visits to a dentist unless they feel that a dentist can relieve specific problems. When interpreted according to the Motivational Theory of Life Span Development, discontinuation of oral care by frail elderly could be viewed as a manifestation of adaptive development. Simple measures aimed at recognizing indicators for poor oral care behavior, and providing appropriate information and support, are discussed.