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

NCT07580534 | Enrolling By Invitation

• 1 other identifier: Al-Azhar University, (Assiut B
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Randomized Crossover Clinical Trial Comparing Two Denture Designs (A and B) Retained by Two Locator Systems (ST and EMI) in Implant Overdenture Patients

Conditions

Implant Supported Overdenture; Wear, Occlusal

Keywords

Implant overdentures (IODs); Denture wear; Peri-implant soft tissue health; Crossover clinical trial; Prosthodontic outcomes; attachment system

Outcome Measures

Primary Outcomes (6)

• Retention Force of Implant Overdentures (IODs)

  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)

  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)

  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

  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)

  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)

  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

Study Arms (2)

Arm 1: Denture A with Locator ST Participants receive Denture A retained by Locator ST attachments.

EXPERIMENTAL

Participants receive Denture A retained by Locator ST attachments.

Other: Crossover Assignment

Denture A with Locator EMI

EXPERIMENTAL

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.

Other: Crossover Assignment

Interventions

Crossover Assignment OTHER

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.

Arm 1: Denture A with Locator ST Participants receive Denture A retained by Locator ST attachments.; Denture A with Locator EMI

Eligibility Criteria

• Age: Up to 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• 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

You may not qualify if:

• 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

Sponsors & Collaborators

• Al-Azhar University: lead

Study Sites (1)

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

Asyut, Egypt

Location

MeSH Terms

Conditions

Tooth Attrition

Condition Hierarchy (Ancestors)

Tooth Wear; Tooth Diseases; Stomatognathic Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: HEALTH SERVICES RESEARCH
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Model Details: This randomized crossover clinical trial investigates the impact of two different denture designs (Denture A and Denture B) retained by two locator attachment systems (Locator ST and Locator EMI) in patients rehabilitated with mandibular implant overdentures (IODs). The study aims to evaluate both clinical performance and patient-reported outcomes, providing a comprehensive assessment of treatment effectiveness. Each participant receives both denture designs in a crossover sequence, allowing direct within-subject comparison and minimizing inter-patient variability. The locator systems (ST and EMI) are tested with each denture design to determine whether attachment type influences patient satisfaction, prosthesis function, and oral health-related quality of life. Primary outcomes are measured using the Arabic version of the Oral Health Impact Profile-19 (OHIP-19) and Visual Analog Scales (VAS) for satisfaction domains (comfort, chewing ability, speech clarity, esthetics, and retention

Study Record Dates

• First Submitted: April 25, 2026
• First Posted: May 12, 2026
• Study Start: June 1, 2024
• Primary Completion: June 1, 2026
• Study Completion (Estimated): August 1, 2026
• Last Updated: May 12, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

EG (1)