Partial Edentulism Class IVRCTNCT07886008
Comparative Assessment of Marginal Bone Loss Around the Implant When Using PEEK With Composite Veneering Versus Monolithic Zirconia Restorations as Implant Restorations
A study testing PEEK (Polyetheretherketone) screw-retained implant restoration veneered with composite and Monolithic zirconia screw-retained implant restoration in people with Partial Edentulism Class IV, run by Cairo University at 1 site in Egypt.
Trial summary
This study compares two different materials used for screw-retained dental implant restorations in the front of the upper jaw (the "esthetic zone"). The goal is to determine which material is better at preserving the bone level around the implant over time and how this will affect the survival rate of the restorations Read more about this study
- Who is it for?
- Ages 20 to 50 years
- Conditions the study is for
- Partial Edentulism Class IV
- What is being tested?
- PEEK (Polyetheretherketone) screw-retained implant restoration veneered with composite and Monolithic zirconia screw-retained implant restoration
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 48 participants
- Where
- 1 siteEgypt
- Study dates
- 10 Apr 2025to 30 Aug 2026
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 20 to 50 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Missing Teeth: Patients must be partially edentulous, specifically missing teeth in the upper (maxillary) aesthetic zone
- Age: between the ages of 20 and 50 years.
- Systemic Health: Individuals must be free from any systemic diseases
- Jaw Relationship: Participants must have an Angle's Class I skeletal relationship.
- Facial Structure: Patients must demonstrate normal facial symmetry
Who cannot join
- Jaw Joint Issues: Patients suffering from Temporomandibular Disorder (TMD) problems.
- Smoking Status: Heavy smokers are excluded from the study.
- Bone and Tissue Health: Patients with existing bone loss in the anterior (front) area, flabby tissues, or a sharp residual ridge.
- Neuromuscular Disorders: Any patient with a neuromuscular disorder is ineligible
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Marginal Bone Loss Around the Implant of Screw-retained Implant Restorations in the Esthetic Zone Using PEEK With Composite Veneering Versus Monolithic Zirconia Restorations Using a Fully Digital Workflow: A Randomized Controlled Clinical Trial
This study compares two different materials used for screw-retained dental implant restorations in the front of the upper jaw (the "esthetic zone"). The goal is to determine which material is better at preserving the bone level around the implant over time and how this will affect the survival rate of the restorations
Read the detailed description
Purpose of the Study
The primary purpose of this randomized controlled clinical trial is to compare two specific materials used for screw-retained dental implant restorations in the "esthetic zone" (the front of the upper jaw) to see which one better preserves the surrounding bone.
Core Research Objective
The study aims to evaluate whether PEEK (Polyetheretherketone) veneered with composite is superior to monolithic zirconia in decreasing marginal bone loss around dental implants.
The Scientific Rationale
Researchers are investigating these materials for several key reasons:
- Stress Distribution:** PEEK has an elastic modulus (flexibility) similar to human bone. It is believed this may help avoid high-stress transfer at the bone-implant interface and reduce "stress shielding," which can lead to bone loss.
- Improving on Current Standards:** While monolithic zirconia is popular due to its high esthetic potential and biocompatibility, it is very rigid, and common failures include the chipping of veneering porcelain.
- Establishing Gold Standards:** The study seeks to determine a "gold standard" for screw-retained restorations that can maximize implant survival rates and enhance the quality of life for partially edentulous patients.
- Clinical Guidance:** The findings are intended to provide clinicians with specific precautions and recommendations for implant planning in the esthetic zone to enhance overall treatment success.
Primary and Secondary Outcomes
To fulfill this purpose, the study measures two main factors:
- Primary Outcome: The amount of marginal bone loss** (measured in millimeters) using digital X-rays at 6 and 12 months.
- Secondary Outcome:The survival rate of the different types of restorations over the one-year follow-up period.
- Conditions
- Partial Edentulism Class IV
- Being tested
- PEEK (Polyetheretherketone) screw-retained implant restoration veneered with composite, Monolithic zirconia screw-retained implant restoration
- Keywords
- Marginal Bone Loss, Survival rate, Screw retained FPD, Zirconia, PEEK
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PEEK (Polyetheretherketone) screw-retained implant restoration veneered with compositeProcedure or surgery
Also called PEEK
To distinguish the interventions in this specific study from those in other clinical trials, the following unique technical and procedural details should be noted:
- Specific Material Combination: The primary intervention uses PEEK (Polyetheretherketone) specifically veneered with Visio-lign composite**, a combination chosen to mimic the elastic modulus of human bone and reduce stress shielding.
- Targeted Anatomical Site: The study is exclusively limited to the maxillary esthetic zone** (upper front teeth), where both mechanical stress and esthetic demands are highest.
- Fully Digital Workflow: Unlike studies that may use conventional impressions, this protocol utilizes a fully digital workflow**, including digital intraoral scans and CAD/CAM fabrication for both the PEEK and zirconia restorations.
- Prosthetically Driven Surgical Guidance:** The placement of the two implants is "prosthetically driven," meaning the final tooth position dictates the surgey
Monolithic zirconia screw-retained implant restorationProcedure or surgery
Also called Zirconia
In this study, the comparator group (the control group) receives a monolithic zirconia screw-retained restoration. This group serves as the standard clinical benchmark against which the experimental PEEK-composite material is measured.
The specific details that distinguish this intervention from others include:
- Material Selection: The restoration is made of monolithic zirconia**, a high-strength ceramic known for its biocompatibility and esthetic potential, but which is significantly more rigid than the experimental PEEK material.
- Fully Digital CAD/CAM Workflow: Unlike traditional methods, the zirconia restoration is designed and fabricated using a fully digital workflow**, including digital intraoral scans and computer-aided manufacturing.
- Specific Anatomical Placement: This intervention is applied specifically to two dental implants** located in the maxillary esthetic zone
| Study group | Role | What they receive |
|---|---|---|
| Marginal bone loss around Monolithic Zirconia screw-retained implant restoration | Active comparator | The "gold standard" or comparator group (Control Group) consists of Monolithic Zirconia screw-retained restorations.
The specific intervention for this group includes the following steps:
Surgical Phase: Each participant receives two dental implants installed in the esthetic areas of the maxillary arch.
Surgical Guidance: The implants are prosthetically driven and installed with the help of digitally constructed surgical guides.
Provisional Phase: Temporary (provisional) restorations are loaded immediately after implant insertion and worn during the healing phase.
Final Restoration: After three months of healing, the final fixed partial denture-made of monolithic zirconia-is inserted.
Workflow: The entire process follows a fully digital workflow.
Maintenance: Patients receive regular maintenance instructions and are recalled for follow-up assessments Receives: Procedure: Monolithic zirconia screw-retained implant restoration |
| Marginal bone loss around PEEK screw-retained implant restoration veneered with composite | Experimental | In this clinical trial, the intervention group receives PEEK (Polyetheretherketone) screw-retained restorations veneered with composite
The specific steps and components for this group include:
* Implant Placement:** Each participant receives two dental implants in the upper front (maxillary esthetic) zone.
* Surgical Guidance:** The implants are placed using a prosthetically driven approach with the aid of digitally constructed surgical guides.
* Provisional Loading:** Temporary restorations are loaded immediately after the implants are inserted and worn throughout the healing phase.
* Final Restoration:** After three months of healing, the final fixed partial denture-made of PEEK and veneered with "Visio-lign" composite-is inserted.
* Digital Workflow:** The design and fabrication of the restoration follow a fully digital CAD/CAM workflow.
* Monitoring:** The health of the bone around the implants is measured using digital X-rays at 6 and 12 months Receives: Procedure: PEEK (Polyetheretherketone) screw-retained implant restoration veneered with composite |
What is being measured
The primary outcome is the main question the study is designed to answer.
Margina Bone Loss
Method: The marginal bone height level is radiographically assessed using Digital Subtraction Radiography with the DIGORA system.
Technique: Researchers utilize a long paralleling technique to measure bone height in millimeters from the mesial and distal aspects of the implants.
Standardization: To ensure consistency across different time points, a customized occlusal bite index (made of hard acrylic attached to a film holder) is used to standardize the film placement and the angle of the X-ray cone.
Measured: the assessments are conducted at the following intervals: Baseline (T0): Immediately after the placement of the implants. 6 Months (T4): Six months after the initial implant placement. 12 Months (T5): One year after the initial implant placement
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Oct 2026
- Study start10 Apr 2025
- Primary completion10 Aug 2026
- Study completion30 Aug 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (5)Papers the sponsor has linked to this study.
- Other trials for Partial Edentulism Class IVStudies of the same condition, open and under way.
- More trials run by Cairo UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 48 participants (actual)
Sponsor and investigators
- Lead sponsor
- Cairo University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Heba Hossam Abd Elfattah Ahmed, Cairo University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07886008
- Sponsor's protocol ID
- 6-2-1
- Acronym
- RCT
- Status last verified
- Oct 2026
- First submitted
- 2 Apr 2026
- Last updated
- 21 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: * Confidentiality and Privacy\*\*: All participant information is kept in safekeeping to protect their identity. Records containing names or personal identifiers are stored separately from the study records and are identified only by code numbers to maintain anonymity. * Restricted Access to Personnel\*\*: Access to the full, unblinded datasets is limited to the principal investigator and the study supervisors. Other project team members only receive data that has been blinded to any identifying information. * Security Measures\*\*: Data is stored on a personal laptop and encrypted using password protection to prevent unauthorized access. Physical records are kept in locked file cabinets. Institutional and Academic Requirements: The data is primarily collected for a master's degree thesis at Cairo University. Thedissemination policy requires the trial to be described in a thesis form and approved by the department before it can be published internationally Ethical Constraints
Publications
Moustafa Ali, R., Helmy, M. (2020). 'Poly ether-ether ketone veneered with composite Versus Porcelain fused to metal Full arch fixed screw retained prosthesis for atrophied mandibular ridges. One year randomized clinical and radiographic trial study', Egyptian Dental Journal, 66(Issue 4 - October (Fixed Prosthodontics, Removable Prosthodontics and Dental Materials)), pp. 2439-2449. doi: 10.21608/edj.2020.35663.1173
Reissmann DR, Dard M, Lamprecht R, Struppek J, Heydecke G. Oral health-related quality of life in subjects with implant-supported prostheses: A systematic review. J Dent. 2017 Oct;65:22-40. doi: 10.1016/j.jdent.2017.08.003. Epub 2017 Aug 5.
PubMed 28789860Martins RG, Castro TS, Dib LL, Gehrke SA, Mesquita AMM. Influence of Restorative Material on the Distribution of Loads to the Bone in Hybrid Abutment Crowns-In Vitro Study. Medicina (Kaunas). 2023 Jun 22;59(7):1188. doi: 10.3390/medicina59071188.
PubMed 37512000Yazigi C, Kern M, Chaar MS, Libecki W, Elsayed A. The influence of the restorative material on the mechanical behavior of screw-retained hybrid-abutment-crowns. J Mech Behav Biomed Mater. 2020 Nov;111:103988. doi: 10.1016/j.jmbbm.2020.103988. Epub 2020 Jul 26.
PubMed 32799134Belser UC, Mericske-Stern R, Bernard JP, Taylor TD. Prosthetic management of the partially dentate patient with fixed implant restorations. Clin Oral Implants Res. 2000;11 Suppl 1:126-45. doi: 10.1034/j.1600-0501.2000.011s1126.x.
PubMed 11168262