Maxillary implant overdentures retained by use of bars or locator attachments: 5-year findings from a randomized controlled trial.

Background
Edentulous patients wearing a maxillary denture can experience problems. Lacking prosthesis stability and retention, combined with an increased gag-reflex are the most profound complaints. Current research on implant supported overdentures shows an increased stability and retention, while decreasing gag-reflexes by reducing palatal coverage. However, consensus on treating the edentulous maxilla with an implant overdenture has not been reached. One of the aspects in overdenture treatment is the used prosthetic anchorage system. Currently literature reports on different anchorage systems, but randomised controlled trials are limited to short term results. The clinical, radiographic and patient related outcome measures were previously evaluated in 50 patients after 1 year follow-up. Patients with complaints of their conventional maxillary denture were randomly assigned to either bar (n=25) or Locator (n=25) attachment groups. All patients received four maxillary implants, placed by surgeon. After healing, the prosthesis was made by one prosthodontics. Patient related outcomes were examined through patient questionnaires before surgery and at 1 year after placement of the prosthesis. Clinical and radiographic parameters were examinated at 1 month and 1 year after placement of the prosthesis. The conclusion of the 1-years follow up results reviewed that both anchorage systems are associated with high patient satisfaction, low peri-implant bone loss and healthy peri-implant tissues (Boven GC, Meijer HJA, Vissink A, Raghoebar GM. Maxillary implant overdentures retained by use of bars or locator attachments: 1-year findings from a randomized controlled trial. J Prosthodont Res. 2020;64(1):26-33. doi:10.1016/j.jpor.2019.04.013). For the current study we want to compare the clinical, radiographical and patient related outcome measures after 5 years.


Aim: to assess the 5-year results of the clinical, radiographical and patient related outcome measures in patients treated with maxillary implant overdenture therapy, retained by bar or locator attachments.

Study design: prospective comparative trial

Study population: 50 patients

Intervention: no

Main study parameters/eindpoint: the primary outcome measure is peri-implant bone loss during the follow-up of 5 years. The secondary outcome measures are implant survival, changes in clinical (probing depth, modified bleeding index, gingiva index) parameters and patient satisfaction (validated questionnaires).

Expected results: Satisfying results for both groups of patients. The patients will have no additional research appointments.

Satisfying results for both groups of patients, non-inferiority

5 years after placement prosthesis (baseline and 1-year results in previous study)