[Late results with hybrid dentures in low-income patients. An investigation at the Cantonal Public Dental Clinic of Zurich].

72 patients who had received overdentures at the Cantonal Public Dental Clinic of Zurich during a period of ten years (1970-1980) were called for re-examination. Results obtained were evaluated according to an analogous survey which had been conducted 12 years previously at the same public dental clinic (Wiesmann 1975): The test subjects of both studies belonged exclusively to the lower-income population and treatment was performed by post-graduate dentists employed at the clinic. A comparison with Wiesmann's findings demonstrated a definite improvement in the general oral health conditions of these wearers of hybrid prosthesis. Since 1972 a recall system has been successively introduced which, for the greatest part, offers the most probable explanation for these positive findings. Each patient was summoned for at least one dental examination per year, thereupon presenting better results in regard to average plaque index, carious lesions, degree of gingival inflammation, probing depth and functionality of the prosthetic appliance, a marked difference to those patients who did not participate in such a dental maintenance program. Therefore, the regular motivation and supervision of patients is mandatory for long-term success of overdenture treatment.