Color Stability of Dental CeramicsNCT07786272

Impact of Khat Chewing on Color Stability and Patient Satisfaction of Multilayer Zirconia and Feldspathic Veneer Zirconia.

A study testing Multilayer Zirconia Crowns and Feldspathic Veneered Zirconia Crowns in people with Color Stability of Dental Ceramics and Zirconia Restorations, run by Thamar University at 1 site in Yemen.

Active, not recruiting

Under way, not looking for participants. Everyone needed has enrolled. The study is still running.

Official record

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Trial summary

Who is it for?: Ages 18 to 60 yearsHealthy volunteers can take part
Conditions the study is for: Color Stability of Dental Ceramics, Zirconia Restorations, Khat Chewing Effects
What is being tested?: Multilayer Zirconia Crowns and Feldspathic Veneered Zirconia Crowns
Type of treatment: Medical device
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 10 participants
Where: 1 siteYemen
Study dates: 1 Jan 2026to 12 Mar 2027
Phase: Interventional
Are there results?: Not yet: the study is under way

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 18 to 60 years
All sexes
Healthy volunteers accepted
Adult

Who may be able to join

Age > 18 years old.
Participants required crowns with proper endodontic treatment.
Participants with stable normal occlusion.
Khat chewer.
Participants required crowns for posterior teeth (premolar and molar) in the side of khat chewing.
Participants with extensive decay, cracks, or large restorations that necessitate a crown.

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Participants wishing to improve the appearance of discolored or damaged teeth may be suitable candidates for crowns.
Good oral hygiene.
Availability for follow-up

Who cannot join

Participants with high caries index.
Participants with parafunctional habits as clenching/bruxism.
Severe periodontal disease.
Participants not indicated for crowns.
Allergy to materials.

Trial locations and contacts

1 site in 1 country.

Yemen1 site

Thamar University , Faculty of Dentistry
Dhamar

Other trials in Yemen

About this study

Official title: Impact of Khat Chewing on Color Stability and Patient Satisfaction of Multilayer Zirconia and Feldspathic Veneer Zirconia: A Split-Mouth Clinical Trial.

This study aims to evaluate and compare the impact of khat chewing on the color stability and patient satisfaction of multilayer zirconia and feldspathic veneered zirconia restorations. A split-mouth clinical trial design is utilized to assess color changes using a spectrophotometer and patient satisfaction via a structured questionnaire over the follow-up period.

Conditions: Color Stability of Dental Ceramics, Zirconia Restorations, Khat Chewing Effects, Dental Restoration Staining
Being tested: Multilayer Zirconia Crowns, Feldspathic Veneered Zirconia Crowns
Keywords: Multilayer Zirconia, Feldspathic Veneered Zirconia, Split-Mouth Study, Spectrophotometer, Patient Satisfaction
Medical subject headings: Patient Satisfaction

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Multilayer Zirconia CrownsDevice
Multilayered zirconia restorations placed in one arch.
Feldspathic Veneered Zirconia CrownsDevice
Feldspathic veneered zirconia Restorations Placed in the opposing arch.

Study groups in NCT07786272
Study group	Role	What they receive
Multilayer Zirconia Group	Experimental	Restorations fabricated using multilayer zirconia in one arch. Receives: Device: Multilayer Zirconia Crowns
Feldspathic Veneered Zirconia Group	Active comparator	Restorations fabricated using feldspathic veneered zirconia in the opposing arch. Receives: Device: Feldspathic Veneered Zirconia Crowns

What is being measured

The primary outcome is the main question the study is designed to answer.

Color stability
Assessment of color change (delta E) of the restorations measured using a spectrophotometer.
Measured: Baseline, 3 months, and 6 months

Secondary outcomes (1)

Patient Satisfaction
Evaluation of patient satisfaction with aesthetic appearance and overall restoration outcome measured using a standardized questionnaire or Visual Analog Scale (VAS).
Measured: 6 months

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

1 Jan 202612 Mar 2027

First posted25 Aug 2026
Study start1 Jan 2026
Primary completion1 Feb 2027 (estimated)
Study completion12 Mar 2027 (estimated)

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Other trials for Color Stability of Dental CeramicsStudies of the same condition, open and under way.
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: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Model description: This is a split-mouth clinical trial. Each participant receives both restoration types simultaneously on the same side: multilayer zirconia in one arch (maxillary or mandibular) and feldspathic veneered zirconia in the opposing arch, assigned randomly.
Masking: Double blind
Who is masked: Participant, Outcomes assessor
Enrolment: 10 participants (estimated)

IDs, dates and publications

ClinicalTrials.gov ID: NCT07786272
Sponsor's protocol ID: EC/FD/2025/005
Status last verified: Aug 2026
First submitted: 21 Aug 2026
Last updated: 25 Aug 2026
Results posted: No
Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No
Individual data sharing: No: Individual participant data will not be shared to protect participant privacy and maintain confidentiality.

Study at a glance

From the registry record, last updated by the sponsor on 25 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Impact of Khat Chewing on Color Stability and Patient Satisfaction of Multilayer Zirconia and Feldspathic Veneer Zirconia: A Split-Mouth Clinical Trial.
ClinicalTrials.gov ID: NCT07786272
Acronym / sponsor ID: EC/FD/2025/005
Conditions: Color Stability of Dental Ceramics, Zirconia Restorations, Khat Chewing Effects, Dental Restoration Staining
Keywords: Multilayer Zirconia, Feldspathic Veneered Zirconia, Split-Mouth Study, Spectrophotometer, Patient Satisfaction
Study type: Interventional
Recruitment status: Active, not recruiting
Enrolment: 10 participants (estimated)
Lead sponsor: Thamar UniversityUniversity, hospital or other
Study start: 1 Jan 2026 (actual)
Primary completion: 1 Feb 2027 (estimated)
Study completion: 12 Mar 2027 (estimated)
First posted: 25 Aug 2026 (actual)
Results: Not posted in the source record

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Study design

Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: Double blind (participant, outcomes assessor)
Number of arms: 2
Model description: This is a split-mouth clinical trial. Each participant receives both restoration types simultaneously on the same side: multilayer zirconia in one arch (maxillary or mandibular) and feldspathic veneered zirconia in the opposing arch, assigned randomly.

Arm	Type	Receives
Multilayer Zirconia Group	Experimental	Device: Multilayer Zirconia CrownsRestorations fabricated using multilayer zirconia in one arch.
Feldspathic Veneered Zirconia Group	Active comparator	Device: Feldspathic Veneered Zirconia CrownsRestorations fabricated using feldspathic veneered zirconia in the opposing arch.

Who may qualify

Ages: 18 to 60 years
Sex: All
Healthy volunteers: Accepted
Age groups: Adult

Key inclusion criteria (9 listed)

Age > 18 years old.
Participants required crowns with proper endodontic treatment.
Participants with stable normal occlusion.
Khat chewer.
Participants required crowns for posterior teeth (premolar and molar) in the side of khat chewing.

Key exclusion criteria (5 listed)

Participants with high caries index.
Participants with parafunctional habits as clenching/bruxism.
Severe periodontal disease.
Participants not indicated for crowns.
Allergy to materials.

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
Multilayer Zirconia CrownsMultilayered zirconia restorations placed in one arch.	Device	Multilayer Zirconia Group
Feldspathic Veneered Zirconia CrownsFeldspathic veneered zirconia Restorations Placed in the opposing arch.	Device	Feldspathic Veneered Zirconia Group

Primary outcome

Color stability
Time frame: Baseline, 3 months, and 6 months
Assessment of color change (delta E) of the restorations measured using a spectrophotometer.

1 secondary outcome

Patient Satisfaction
Time frame: 6 months

Results and safety

This study is still under way. Results are not available in the source record yet.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 25 Aug 2026.
Individual participant dataSharing planned: No. Individual participant data will not be shared to protect participant privacy and maintain confidentiality.

Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

The record lists no contact. Use the official record to reach the sponsor.

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 9 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: under way, not looking for participants, as of the sponsor's last update on 25 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Yemen. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Color stability (time frame: Baseline, 3 months, and 6 months). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT07786272.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 25 Aug 2026.