What is the evidence on the added value of implant-supported overdentures? A review.

Background: Implant-supported overdentures (IODs) have been reported to increase patients' oral health-related quality of life (OHRQoL) in comparison with conventional dentures (CDs); however, the conclusiveness of evidence on the clinical effectiveness and value for money of IODs versus CDs remains unclear.
Purpose: To review how the added value of IODs is demonstrated in the literature.
Materials and Methods: MEDLINE, EMBASE, and the Cochrane Database were searched for randomized control trials, controlled clinical trials, and prospective cohort studies containing evaluations of the economic and health benefits and costs of IODs. Information about the clinical effectiveness, such as magnitude of bite forces or chewing efficacy, OHRQoL, costs, and cost-effectiveness of IODs, was extracted.
Results: A total of 17 articles were included, reporting 15 economic evaluations: 11 cost-utility analyses (CUAs), 2 of which were combined with a cost-effectiveness analysis (CEA), and 2 cost-benefit analyses (CBAs). Seven CUAs used the Oral Health Impact Profile (OHIP) questionnaire while four used satisfaction questionnaires to assess the OHRQoL. One study applied quality-adjusted prosthesis years (QAPYs) for this purpose. The CBAs expressed both the beneficial outcome and the costs of the IOD in monetary terms. The included studies employed a large variety of economic evaluation methods, which limited cross-study comparability.
Conclusions: On the basis of existing economic evaluations, IODs have frequently been suggested to be a cost-efficient treatment alternative to CDs; however, the comparability between the various economic evaluation studies was limited due to the different outcome measures used. In addition, it remains unclear whether the additional health benefits of IODs outweigh the higher costs. This is largely dependent on the decision maker's valuation of oral health outcomes. Future research is encouraged to further elucidate patient willingness to pay for IODs and the societal return on investing in IODs more generally.
(© 2021 The Authors. Clinical Implant Dentistry and Related Research Published by Wiley Periodicals LLC.)