Because oral health among residents of German nursing homes is inadequate, this intervention study evaluated the effects of dental training for nurses and nursing assistants (RN and RA) in homes for the elderly on their assessment of oral health in residents and, as a consequence, on the status of residents' oral health. 53 residents and the RNs and RAs from three homes for the elderly participated in this study. The nursing staff received training in dental health care. As primary outcome, the competence in performing the Brief Oral Health Examination (BOHSE) was measured at baseline date and four months after training. Additional outcome measures were dental and denture hygiene in residents, functional status of dentures, and treatment needs. Dental training was shown to improve the nursing staff's competences in oral health assessment in tendency. Residents' oral hygiene improved significantly, whereas no relevant effects on hygiene and functional status of dentures were registered. The need for dental treatment turned out to be considerable at both measurements. Modifications in test tools with identification of dental treatment needs seem to be indicated in order to improve cooperation between nursing staff and dentists in homes for the elderly.