Mandibular Overdentures Retained by Four Locator Attachments Versus Four-Implant Bar Attachments

ConditionBone Loss

Trial statusRecruiting

Trial phaseNot listed

Trial typeObservational

Biological sexAll

Age40-70

SponsorMenoufia University

About this trial

This 10-year retrospective study investigates residual ridge changes in edentulous patients treated with mandibular overdentures (ODs) retained by either four Locator attachments or a four-implant bar system. Although two-implant ODs are well established, four-implant configurations may offer enhanced stability and function. Locator and bar attachments are commonly used, but their long-term effects on bone resorption patterns-especially posterior mandibular and anterior maxillary resorption-remain unclear. By standardizing implant positions, this study aims to directly compare the two systems to help guide clinicians in selecting the most effective attachment type for long-term success.

Eligibility criteria

This trial does not accept healthy volunteers

Qualifiers

Completely edentulous mandible and maxilla for at least 12 months.

Four interforaminal dental implants placed in the lateral incisor and first premolar regions.

Opposing maxillary complete denture constructed using a muco-compressive impression technique, with maximum denture base extension and lingualized occlusion.

Mandibular bone height between 15-25 mm at the symphysis region as measured on panoramic radiograph.

Disqualifiers

Systemic diseases affecting bone metabolism.

Parafunctional habits (e.g., bruxism).

Smokers of more than 10 cigarettes/day or those with alcohol abuse.

Patients with implant failures, missing follow-up data, or implants placed outside the interforaminal region.

Trial population

The study population consisted of completely edentulous patients who received mandibular overdentures retained by four dental implants placed in the interforaminal region. Patients were selected retrospectively based on having been treated with either four Locator attachments or a four-implant bar attachment system and followed for a minimum period of 10 years. All participants had similar implant positioning (lateral incisor and first premolar areas) and were free from systemic conditions that could affect bone healing or implant success. Inclusion criteria required good oral hygiene compliance and regular follow-up records. Exclusion criteria included uncontrolled systemic diseases, history of head and neck radiation, and lack of long-term follow-up data.

Trial design

Design model

Cohort

Time perspective

Retrospective

Treatments tested in this trial

Four Locator Attachments, Four Bar Attachment System
Other intervention
This study retrospectively evaluated two types of implant-retained mandibular overdenture attachment systems placed in edentulous patients over a 10-year period. All patients received four dental implants placed in the interforaminal region (lateral incisor and first premolar areas). In the Locator group, each implant was restored with an individual Locator attachment, allowing for independent retention and easier hygiene access. In the Bar group, the four implants were splinted together with a rigid metal bar, and the overdenture was attached using clips that engaged the bar, offering splinted support and enhanced load distribution. Both interventions were designed to support mandibular overdentures and were compared in terms of their long-term effects on posterior mandibular ridge resorption, marginal bone loss around implants, and anterior maxillary ridge resorption.

Treatment groups

22 Participants

are divided into 2 treatment groups

Group A: Group I - Locator Attachments1 intervention

Group B: Group II - Bar Attachments1 intervention

Trial outcomes

Primary outcomes

Marginal Bone Loss (MBL)

Crestal bone loss around dental implants

Time frame

10 years

Sponsors and contacts

Click on the lead sponsor to view all of their trials.

Menoufia University

Lead sponsor

Mansoura University

Collaborator

Source ClinicalTrials.gov

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