Multicentre prospective evaluation of implant-assisted mandibular bilateral distal extension removable partial dentures: Patient satisfaction

Objective To compare the levels of patient satisfaction with either conventional mandibular bilateral distal extension partial dentures or those assisted by bilateral distal implants. Materials and methods Forty-eight participants who were dissatisfied with their existing conventional mandibular distal extension dentures opposing complete maxillary dentures were selected for a multicentre prospective study in New Zealand, Colombia and the Netherlands. A control group of 12 participants in New Zealand received conventional mandibular partial dentures. Three test groups involving 36 participants in New Zealand (12), Colombia (12) and the Netherlands (12) received bilateral distal implants in the second molar regions. After conventional loading, the test group participants initially had healing caps placed on the distal implants providing support only, followed after approximately 6 months by ball abutments (retentive anchors) for support and retention. Patient outcomes were determined with questionnaires completed at specific stages of the study for up to 3 years. Results Visual analogue scale, Likert and oral health impact questionnaires before and after treatment indicated improved results. There were significantly improved parameters of overall satisfaction, stability, chewing and appearance after 3 years (P < 0.05). There were also improvements on stability, chewing and overall satisfaction. Speech also improved, but not significantly. Ball abutments (retentive anchors) on the distal implants, as opposed to healing caps improved patient satisfaction for stability, chewing and overall satisfaction. Changing to ball abutments (retentive anchors) revealed significant improvement by participant response when evaluating parameters of stability, chewing and overall satisfaction (P < 0.05). Conclusion Mandibular implant-assisted removable partial dentures are a preferable treatment option for patients with complaints about their conventional distal extension partial dentures.