Clinical Evaluation of Conventional and 3D-printed Implant-supported Overdentures Retained With New Attachment Systems (IODs)

May 7, 2026 updated by: Mohamed Moustafa, Al-Azhar University
Randomized Crossover Clinical Trial Comparing Two Denture Designs (A and B) Retained by Two Locator Systems (ST and EMI) in Implant Overdenture Patients

Study Overview

Status

Enrolling by invitation

Intervention / Treatment

Detailed Description

This randomized crossover clinical trial evaluates patient-reported outcomes and clinical performance of implant overdentures (IODs) using two different denture designs (A and B) retained by two locator attachment systems: Locator ST and Locator EMI. Each participant will receive both denture designs in a crossover sequence, allowing direct within-subject comparison.

Study Type

Interventional

Enrollment (Estimated)

20

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Asyut, Egypt
        • Faculty of Dental Medicine, Al-Azhar University, (Assiut Branch)

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Completely edentulous patients
  • Non-smokers
  • Patients free from intra-oral diseases that may affect implant-overdenture prognosis
  • Patients free from systemic conditions that may influence bone resorption or implant success
  • Able and willing to comply with study visits and follow-up schedule

Exclusion Criteria:

  • Smokers or tobacco users
  • Presence of active oral lesions, infections, or mucosal pathology
  • Systemic diseases affecting bone metabolism (e.g., uncontrolled diabetes, osteoporosis requiring bisphosphonates)
  • History of head and neck radiation
  • Severe parafunctional habits (e.g., bruxism)
  • Inability to attend follow-up appointments or provide informed consent

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Health Services Research
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Arm 1: Denture A with Locator ST Participants receive Denture A retained by Locator ST attachments.
Participants receive Denture A retained by Locator ST attachments.
Participants receive Denture A, a conventional mandibular implant overdenture, retained by two Locator ST attachments placed in the interforaminal region. Outcomes include OHIP-19, VAS satisfaction, retention force, attachment wear, periodontal parameters, and denture tooth wear resistance.
Experimental: Denture A with Locator EMI
Participants receive Denture A retained by two Locator EMI attachments. Same outcome measures as above, allowing comparison of attachment type influence on patient-reported and clinical outcomes.
Participants receive Denture A, a conventional mandibular implant overdenture, retained by two Locator ST attachments placed in the interforaminal region. Outcomes include OHIP-19, VAS satisfaction, retention force, attachment wear, periodontal parameters, and denture tooth wear resistance.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Retention Force of Implant Overdentures (IODs)
Time Frame: Outcome measures were assessed at four clearly defined time points: 1. Baseline (Immediately after overdenture pick up) 2. 3 month follow up 3. 6 month follow up 4. 9 month follow up These time points correspond to the evaluation of implant overdentures
Retention force measured using a digital force gauge to quantify the dislodgement force required to remove the overdenture from the implants. Measurements will be reported in Newtons (N).
Outcome measures were assessed at four clearly defined time points: 1. Baseline (Immediately after overdenture pick up) 2. 3 month follow up 3. 6 month follow up 4. 9 month follow up These time points correspond to the evaluation of implant overdentures
Denture Wear of Implant Overdentures (IODs)
Time Frame: Wear was evaluated relative to the baseline measurement taken immediately after pick-up, with follow-up assessment 9-month per denture type: 1. 3 month follow up 2. 6 month follow up 3. 9 month follow up
Denture wear assessed by measuring surface loss on occlusal surface using digital analysis. Wear depth recorded in millimeters (mm) at each evaluation point.
Wear was evaluated relative to the baseline measurement taken immediately after pick-up, with follow-up assessment 9-month per denture type: 1. 3 month follow up 2. 6 month follow up 3. 9 month follow up
Peri-implant Soft Tissue Health (Modified Plaque Index and Modified Bleeding Index Scores)
Time Frame: Assessments performed over an 18-month total follow-up period, at the following intervals: 1 - Immediately after pick-up (baseline) 2 - 3 months 3 - 6 months 4 - 9 months 5 - 12 months 6 - 15 months 7 - 18 months

Peri-implant soft tissue health assessed using the Modified Plaque Index (mPI) and Modified Bleeding Index (mBI).

Both indices are ordinal clinical scales scored according to standard peri-implant evaluation criteria:

mPI range: 0-3 0 = no plaque 3 = abundant plaque

mBI range: 0-3 0 = no bleeding 3 = profuse bleeding

Interpretation:

Higher scores indicate worse peri-implant soft tissue health.

Unit of Measure:

Ordinal index scores (mPI, mBI)

Assessments performed over an 18-month total follow-up period, at the following intervals: 1 - Immediately after pick-up (baseline) 2 - 3 months 3 - 6 months 4 - 9 months 5 - 12 months 6 - 15 months 7 - 18 months
Crestal bone level changes
Time Frame: Radiographic measurements performed over an 18-month total follow-up period, at the following intervals: 1 - Immediately after pick-up (baseline) 2 - 3 months 3 - 6 months 4 - 9 months 5 - 12 months 6 - 15 months 7 - 18 months
Crestal bone levels measured on standardized periapical radiographs taken with a paralleling technique. Bone level is defined as the distance from the implant shoulder to the first bone-to-implant contact.
Radiographic measurements performed over an 18-month total follow-up period, at the following intervals: 1 - Immediately after pick-up (baseline) 2 - 3 months 3 - 6 months 4 - 9 months 5 - 12 months 6 - 15 months 7 - 18 months
Oral Health-Related Quality of Life (OHIP-19 score)
Time Frame: OHIP-19 scores recorded three times during each 9-month denture phase: 1 -Before pick-up 2 - Immediately after pick-up 3 - At 9 months follow up

Oral health-related quality of life assessed using the Oral Health Impact Profile-19 (OHIP-19) questionnaire. The OHIP-19 consists of 19 items, each scored on a 5-point ordinal scale from 0 to 4:

0 = never 4 = very often

Minimum score: 0 Maximum score: 76 Interpretation: Higher scores indicate worse oral health-related quality of life.

OHIP-19 scores recorded three times during each 9-month denture phase: 1 -Before pick-up 2 - Immediately after pick-up 3 - At 9 months follow up
Patient Satisfaction (Visual Analog Scale Score)
Time Frame: VAS satisfaction scores recorded three times during each 9-month denture phase: 1 - Before pick-up 2 - Immediately after pick-up 3 - At 9 months follow up

Patient satisfaction with the denture and attachment system measured using a 10-point Visual Analog Scale (VAS).

Participants rated their satisfaction on a scale from 0 to 10:

0 = completely dissatisfied 10 = completely satisfied

VAS satisfaction scores recorded three times during each 9-month denture phase: 1 - Before pick-up 2 - Immediately after pick-up 3 - At 9 months follow up

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

June 1, 2024

Primary Completion (Estimated)

June 1, 2026

Study Completion (Estimated)

August 1, 2026

Study Registration Dates

First Submitted

April 25, 2026

First Submitted That Met QC Criteria

May 7, 2026

First Posted (Actual)

May 12, 2026

Study Record Updates

Last Update Posted (Actual)

May 12, 2026

Last Update Submitted That Met QC Criteria

May 7, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Implant Supported Overdenture

Clinical Trials on Crossover Assignment

Subscribe