The effect of mandibular 2-implant overdentures on oral health–related quality of life: an international multicentre study


  • Overdenture Effectiveness Study Team Consortium members: Allen F, Heydecke G, Mojon P, Müller F, Piovano A, Scilingo E, Spielberg GP, Spielberg M, Stoker G, Thomason JM, Wismeijer D.

Corresponding author:

Prof. Jocelyne S. Feine

Oral Health Society Research Unit

Room 102, 3550 University Street

Zip Code H3A2A7

Montreal, QC


Tel.: 514 398-7203

Fax: 514 398 8900




To determine the difference in oral health–related quality of life (OHRQoL) in patients who received mandibular 2-implant overdentures and conventional dentures in a pragmatic international study.

Materials and methods

In this prospective study, data were gathered from 203 edentulous patients (mean age, 68.8; SD: 10.4 years) at eight centres in North America, South America and Europe. The patients were provided with new mandibular conventional dentures or implant overdentures supported by 2 implants and ball attachments and opposed by conventional dentures. At baseline and at 6 months post-treatment, patients rated their oral health–related quality of life using the OHIP-20.


A significantly higher proportion of the participants in the implant group in North America reported improvement in both the psychological and the handicap domains, compared to those who received conventional dentures (93% vs. 52%; < 0.05). In South America, 100% of participants who received implant overdentures reported improvement in physical pain, compared to 66% in the conventional group (< 0.05). Differences in mean change scores among those who expressed improvement were not significantly different between sites or treatments.


Mandibular 2-implant overdentures are more likely than conventional dentures to improve OHRQL for edentulous patients. Cultural differences were also observed in the impact of implant overdentures on the different domains of the OHIP-20.