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Carious Primary MolarsNCT06968767

Preparation Time Of Bioflx Crowns Compared To Zirconia Crowns On Primary Molars

A study testing bioflx crown and zirconia crown in people with Carious Primary Molars, run by Cairo University at 1 site in Egypt.

Not yet recruiting

Opening soon. The study is approved but enrolment has not started yet. Sites may already take enquiries.

Sites and contacts
Official record
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Trial summary

This study aims to evaluate and compare the preparation time required for Bioflx crowns versus zirconia crowns on primary molars through a randomized clinical trial. Primary Objective: To compare the preparation time required for Bioflex crowns and zirconia crowns on primary molars in pediatric patients. Read more about this study

Who is it for?
Ages 4 to 8 yearsHealthy volunteers can take part
Conditions the study is for
Carious Primary Molars
What is being tested?
bioflx crown and zirconia crown
Could I receive a placebo?
No, everyone receives an active treatment
How many people
22 participants
Where
1 siteEgypt
Study dates
15 Jun 2025to 16 Jun 2026
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 4 to 8 years
  • All sexes
  • Healthy volunteers accepted
  • Child

Who may be able to join

  • Children aged between 4 and 8 years with a primary molar that needs to be covered by a crown.
  • Medically healthy children (ASA I or II according to the American Society of Anesthesiologists classification).
  • Children whose parent or guardian is willing to sign an informed consent.
  • Children whose parent or guardian are willing to comply with follow-up visits.
  • Frankl's positive and definitely positive patient.

Who cannot join

  • Molars with severe structural loss that may compromise crown retention.
  • Children with poor oral hygiene that may contribute to higher plaque levels and affect the clinical outcomes of the crown restorations.
  • Children with a history of allergies; known allergies to dental local anesthesia or to the materials used in Biofix crowns.
  • Children with any systemic conditions or disabilities that may affect their ability to participate in the study.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

halah M alshaeri, Bachelor of Dental surgery contact

00201149038858 ext. 002

hala.mosaed@dentistry.cu.edu.eg

Manal A Elshiekh, prof, phd contact

0223642705 ext. 002

rec@dentistry.cu.edu.eg

Egypt1 site
  • Faculty of Dentistry Cairo University

    Cairo, Egypt, 12613

    faculty of dentistry cairo university, 0020223642705, rec@dentistry.cu.edu.eg

    hala mosaed ali alshaeri, bachelore of dental science

Other trials in Egypt

About this study

Official title: Evaluation Of Preparation Time Of Bioflx Crowns Compared To Zirconia Crowns On Primary Molars

This study aims to evaluate and compare the preparation time required for Bioflx crowns versus zirconia crowns on primary molars through a randomized clinical trial.

  • Primary Objective: To compare the preparation time required for Bioflex crowns and zirconia crowns on primary molars in pediatric patients.
  • Secondary Objectives:
Read more

To evaluate the clinical performance of Bioflex crowns compared to zirconia crowns, including:

Retention, Patient Satisfaction, Parental Satisfaction, Occlusal Wear and Gingival Health.

the main question it aim to answer: Is there a significant difference in the preparation time required for Bioflx crowns compared to zirconia crowns in the primary molars of pediatric patients?

Read the detailed description

In pediatric dentistry, achieving efficient and aesthetic restoration of primary molars remains a significant challenge, particularly when treating young or anxious patients who may struggle with long or complex procedures. Zirconia crowns are widely used due to their durability, excellent biocompatibility, and natural tooth-like appearance, making them the gold standard for full-coverage aesthetic restorations in children. However, their placement involves extensive tooth preparation, which results in longer chair time and an increased risk of pulp exposure. These factors can negatively impact both treatment outcomes and patient behavior management.

Bioflex crowns have emerged as a potential alternative, offering a more flexible and user-friendly design that simplifies placement and reduces the amount of tooth preparation required. This may result in shorter procedure times and improved patient comfort. Despite these potential benefits, there is currently limited clinical evidence comparing the preparation time and efficiency of Bioflex crowns versus zirconia crowns for restoring primary molars.

This gap in knowledge makes it difficult for clinicians to make fully informed decisions about which crown system offers the best balance of procedural efficiency, aesthetics, and patient cooperation. By directly comparing Bioflex and zirconia crowns in terms of tooth preparation time and overall clinical practicality, the proposed study aims to determine whether Bioflex crowns provide a significant advantage in pediatric settings. The results could help identify the most time-efficient and effective restorative option for primary molars, ultimately improving care outcomes for pediatric patients.

Being tested
bioflx crown, zirconia crown

What participants receive

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

  • bioflx crownOther

    (Group A: Preformed Biofix Crown - Assigned Intervention)

    Crown Selection \& Tooth Preparation:

    Measure the mesiodistal width using calipers to select an appropriately sized crown. If a mesial or distal wall is missing, use the contralateral tooth for size selection. Choose the crown that closely matches the measured mesiodistal width. Select the smallest crown that preserves proximal contacts using a trial-and-error approach. If crimping is necessary, use Howe's pliers.

    Perform 1-1.5 mm occlusal reduction using a tapered diamond bur.

    Reduce proximal areas by approximately 0.5 mm to clear the contact area.

    Crown Placement \& Cementation:

    Ensure a snug fit of the selected crown. Apply a thin layer of glass ionomer cement inside the crown. Seat the crown firmly using finger pressure. Have the child bite down gently to ensure proper seating.

    Final Adjustments \& Cleanup:

    Remove excess cement with floss or an explorer. Verify the crown's fit, occlusion, and stability.

  • zirconia crownOther

    Group B: Preformed Zirconia Crown - Assigned Intervention)

    Crown Selection:

    Measure the mesiodistal width using calipers to select the appropriate crown. If a mesial or distal wall is missing, use the contralateral tooth for size selection. Choose the one that closely matches the mesiodistal width. Select the smallest crown that preserves proximal contacts.

    Tooth Preparation:

    Reduce the occlusal surface by 1.5-2 mm using a tapered diamond bur.

    Reduce interproximal areas by 1-1.5 mm, ensuring a feather-edge finish.

    Perform a 1-2 mm subgingival preparation in passively placed fissure bur.

    Crown Placement \& Passive Fit Check:

    Place the selected crown on the prepared tooth.

    Cementation of the Crown:

    Apply a thin layer of glass ionomer cement inside the crown. Seat the crown with passive finger pressure. Have the child bite down gently to ensure seating.

Study groups in NCT06968767
Study groupRoleWhat they receive
group A performed bioflx crownExperimental(Nu smile, united state) introduced Biofix Crowns and claimed as the first flexible, durable, and esthetic preformed crown for primary molars. Biofix Crowns are monochromatic, metal-free, tooth-colored crowns made up of high-strength resin polymer used in the medical device industry having high strength, flexibility, and durability. These crowns are autoclavable and are like SSC in tooth preparation as claimed by the manufacturer. Their flexibility and snap-fit technology aim to improve retention while minimizing trauma during placement.
Receives: Other: bioflx crown
group B performed zirconia crownExperimentalNuSmile Zirconia Crowns are prefabricated, esthetic full-coverage restorations designed for primary teeth. Known for their superior strength, durability, and natural tooth-like appearance, these crowns provide an excellent alternative to traditional stainless steel crowns. Made from high-quality medical-grade zirconia, they are biocompatible, resistant to chipping, and highly polished to minimize plaque accumulation and gingival irritation. NuSmile Zirconia Crowns require significant tooth preparation for proper fit and retention. They are available in various sizes to accommodate different primary molars and anterior teeth. Their lifelike translucency and color-matching capabilities make them a preferred choice for parents and clinicians.
Receives: Other: zirconia crown

What is being measured

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

  1. prepration time

    measured by stop watch per minutes

    Measured: time frame: T0: 0 basline, follow up 12 month

Secondary outcomes (4)
  1. Occlusal wear of crown

    Measure: By Modified United States Public Health System criteria

    Criteria:

    Alpha: Occlusal surface intact

    Bravo: Wear of occlusal surface without tooth surface exposure

    Charlie: Wear of occlusal surface with exposure

    Measure: By Modified United States Public Health System criteria

    Criteria:

    Alpha: Occlusal surface intact

    Bravo: Wear of occlusal surface without tooth surface exposure

    Charlie: Wear of occlusal surface with exposure

    Measure: By Modified United States Public Health System criteria

    Criteria:

    Alpha: Occlusal surface intact

    Bravo: Wear of occlusal surface without tooth surface exposure

    Charlie: Wear of occlusal surface with exposure

    Measured: T (Time): 12 months Intervals: T0: 0, T1: 3 months, T2: 6 months, T3: 12 months

  2. retention

    Measure: By Modified United States Public Health System criteria

    Criteria:

    Alpha: Intact

    Bravo: Chipped/loss of material

    Charlie: Complete loss of crown

    Measured: Follow-up: 12 months Intervals: T0: 0, T1: 3 months, T2: 6 months, T3: 12 months

  3. Gingival Health

    Measure: By Gingival Index

    Scores:

    0: Healthy gum

    1. Mild inflammation and edematous gingiva, no bleeding on probing
    2. Red edematous and shiny gingiva, bleeding on probing
    3. Red edematous and ulcerated gingiva, spontaneous bleeding

    Measured: 12 months Intervals: T0: 0, T1: 3 months, T2: 6 months, T3: 12 months

  4. Child and parental satisfaction

    Measure: By 5-point Likert scale (Units of measurement)

    1. Very happy
    2. Happy
    3. Neither
    4. Unhappy
    5. Very unhappy Questionnaire Type: Ordinary or N/A (Existing validated tool)

    Measured: T (Time): 12 months Intervals: T0: 0, T1: 3 months, T2: 6 months, T3: 12 months

Timeline

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

  1. First posted13 May 2025
  2. Study start15 Jun 2025 (estimated)
  3. Primary completion15 Jun 2025 (estimated)
  4. Study completion16 Jun 2026 (estimated)

Resources

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
Masking
Single blind
Who is masked
Participant
Enrolment
22 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06968767
Sponsor's protocol ID
PT-BFC VS ZRC
Status last verified
May 2025
First submitted
5 May 2025
Last updated
13 May 2025
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

A study testing bioflx crown and zirconia crown in people with Carious Primary Molars, run by Cairo University at 1 site in Egypt.

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 5 inclusion and 4 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: opening soon, as of the sponsor's last update on 13 May 2025. 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 Egypt. 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?

Contact halah M alshaeri, Bachelor of Dental surgery (00201149038858 ext. 002, hala.mosaed@dentistry.cu.edu.eg), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

prepration time (time frame: time frame: T0: 0 basline, follow up 12 month). It is what the study was designed to measure, not a finding.

Where can I read the original study information?
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 13 May 2025.

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