A NATIONWIDE EVALUATIVE STUDY ON IMPLANT-RETAINED OVERDENTURES

Objectives: In the Netherlands, dental implants have been included in the National Dental Insurance Scheme (NDIS) since 1989. Nowadays, out- of-pocket expenditure is low, making implant treatment financially fea sible for a large group of edentulous, potential implant candidates. T reatment can be performed by both oral surgeons and general dentists. Results of implant treatment in the literature are usually obtained in academic and specialized centers. In contrast to this, the present st udy evaluates the quantitative and qualitative aspects of rehabilitati on with oral implants in combination with an overdenture when applied on a nationwide scale. Methods: For this purpose all patients (n=5410) treated between January 1989 and July 1992 were extensively documente d pre-operatively, implant patients (n=429) were clinically investigat ed by two independent observers and the effect of treatment on denture complaints was assessed by means of a questionnaire (n=460). Results: Only a small proportion of the potential pool of implant candidates i s actually being treated, to a constant number of approximately 2000 p atients a year. The selected patients have major denture problems and have received relatively high levels of prosthetic care during the las t decade. Clinical results are comparable to those reported in the lit erature, implant survival after 3 years for the lower jaw being 96.3% and for the upper jaw 70.4%. Oral hygiene was frequently considered su boptimal and seen in conjunction with marginal inflammation of the per i-implant mucosa. Subjective results were excellent, patients were qui te satisfied with the improvements in the comfort and esthetics of the ir lower denture. Conclusions: Implant-overdenture treatment, within t he guidelines and regulations set by the Dutch NDIS, is a safe and eff ective treatment alternative, in particular for the rehabilitation of the lower jaw. (C) 1997 Elsevier Science Ltd.