Carious Primary MolarsNCT06890949
Occlusal Wear Of Bioflx Crowns Compared To Zirconia Crowns On Primary Molars
A study testing (Group A: Preformed Bioflx Crown) and (Group B: Preformed Zirconia crown) in people with Carious Primary Molars, run by Cairo University at 1 site in Egypt.
Trial summary
The goal of this clinical trial is to evaluate the occlusal wear of Bioflx crowns compared to zirconia crowns in the restoration of primary molars. The main question[s] it aims to answer : " Is there a difference in the occlusal wear of BioFlx crowns compared to zirconia crowns in the restoration of primary molars?"… 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?
- (Group A: Preformed Bioflx Crown) and (Group B: Preformed Zirconia crown)
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 50 participants
- Where
- 1 siteEgypt
- Study dates
- 15 Jun 2025to 16 Jul 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 primary molar that needs to be covered by crown.
- Medically healthy children (ASA I or II according to the American Society of Anesthesiologists classification).
- Children whose parent or guardian are 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 history of allergies; Known allergies to dental local anesthesia or to the materials used in Bioflx 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.
Eithar musa Abdelrahman Hussion, Bachelor of dental science contact
Egypt1 site
Faculty of dentistry cairo university
Cairo ,Giza, Egypt, 12613
Faculty of dentistry cairo university, 0020223642705, rec@dentistry.cu.edu.eg
Eithar M Abdelrahman, BDS
About this study
Official title: Evaluation Of Occlusal Wear Of Bioflx Crowns Compared To Zirconia Crowns On Primary Molars
The goal of this clinical trial is to evaluate the occlusal wear of Bioflx crowns compared to zirconia crowns in the restoration of primary molars.
The main question[s] it aims to answer : " Is there a difference in the occlusal wear of BioFlx crowns compared to zirconia crowns in the restoration of primary molars?" The study will also assess the clinical performance of both types of crowns in terms of retention,gingival health, preparation time, as well as child and parental satisfaction.
Read the detailed description
Occlusal wear is a critical factor in determining the longevity and functional efficiency of dental restorations, especially in pediatric patients. Primary molars undergo significant masticatory forces, which can lead to material wear and affect the restoration's durability. Bioflex (a relatively new material) and zirconia crowns are commonly used for full-coverage restorations in primary molars, yet there is limited research comparing their occlusal wear characteristics. Understanding how these materials perform under occlusal forces can guide clinicians in selecting the most suitable material for pediatric dental restorations Dental caries in primary molars represent a significant issue within pediatric dentistry. In cases where traditional fillings prove insufficient, full coronal coverage becomes necessary. Stainless steel crowns (SSCs) have long been the standard due to their durability and cost-effectiveness, but their metallic appearance has led to increased interest in aesthetic alternatives like zirconia and Bioflx crowns.
Zirconia offers improved aesthetics, biocompatibility, and mechanical strength, though its long-term clinical performance remains underexplored. While zirconia crowns provide durability and superior aesthetics, they require significant tooth preparation, which may compromise tooth structure. Bioflx crowns, a newer option, combine the benefits of stainless steel and zirconia with more flexibility and less tooth reduction. However, comparative studies on their clinical efficacy, occlusal wear, and patient satisfaction are still needed.
Zirconia offers improved biocompatibility, mechanical strength, and enhanced esthetics, but limited comparative data exists regarding its clinical performance.
The growing awareness among parents regarding the importance of maintaining primary teeth until their natural shedding necessitates a thorough evaluation of the durability, wear resistance, retention, gingival response, and overall clinical efficacy of these crown materials. Zirconia crowns have been the preferred choice for aesthetic restorations due to their natural appearance and durability. However, their requirement for excessive tooth preparation poses challenges in pediatric patients.
Bioflx crowns, made from a biocompatible hybrid resin polymer, offer a flexible fit with minimal tooth reduction while maintaining aesthetic appeal. A comprehensive comparison of occlusal wear between these two materials is crucial for assisting clinicians in selecting the most suitable restorative solution for primary molars. This research seeks to offer evidence-based guidance by evaluating the long-term clinical performance of Bioflx crowns in relation to zirconia crowns.
- Conditions
- Carious Primary Molars
- Being tested
- (Group A: Preformed Bioflx Crown), (Group B: Preformed Zirconia crown)
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
(Group A: Preformed Bioflx Crown)Other
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.
Tooth Preparation 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.
(Group B: Preformed Zirconia crown)Other
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 crown that closely matches the measured 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 using a tapered fissure bur.
Crown Placement \& Passive Fit Check
Place the selected crown and check for passive fit.
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 proper seating.
Final Adjustments \& Cleanup
Remove excess cement using floss or an explorer. Verify fit, occlusion, and stability
| Study group | Role | What they receive |
|---|---|---|
| (Group A : preformed Bioflx crown | Experimental | Kids-e-Dental LLP (ANDHERI, MUMBAI, INDIA) introduced Bioflx Crowns and claimed as the first flexible, durable, and esthetic preformed crown for primary molars. Bioflx 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: (Group A: Preformed Bioflx Crown) |
| (Group B: Preformed zirconia crown) | Experimental | NuSmile 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 seeking a highly esthetic and long-lasting pediatric restoration Receives: Other: (Group B: Preformed Zirconia crown) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Occlusal wear of crown
Measure by Modified United States Public Health System criteria:
Alpha: Occlusal surface intact. Bravo: Wear of occlusal surface without tooth surface exposure Charlie: Wear of occlusal surface with exposure
Measured: T (Time): 12months interval T0: 0 T1: 3 month T2: 6month T3: 12 month]
Secondary outcomes (4)
Retention
Measure by :Modified United States Public Health System criteria:Alpha: Intact Bravo:Chipped/loss of material Charlie: Complete loss of crown
Measured: [Time Frame: follow-up:T (Time): 12months interval T0: 0 T1: 3month T2: 6month T3 : 12 month]
Gingival Health
Measure by: Gingival index:
0: healthy gum
- mild discoloration and edematous gingiva no bleeding on probing
- red oedematous and shiny gingiva bleeding on probing
- red oedematous and ulceration gingiva spontaneous bleeding
Measured: T (Time): 12 months interval T0: 0 T1: 3month T2: 6month T3 : 12 month]
preparation time
Measure by : Stopwatch per minutes.
Measured: [Time Frame: baseline]
child and parental satisfaction
Measure by: 5-Point likert's scale units of measurement
- very happy
- happy
- neither
- unhappy
- very unhappy / Questionnaire:Ordinary or N/ A existing validated tool
Measured: [Time Frame: T (Time): 12months interval T0: 0 T1: 3 month T2: 6month T3: 12 month]
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Mar 2025
- Study start15 Jun 2025 (estimated)
- Primary completion15 Jun 2026 (estimated)
- Study completion16 Jul 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Carious Primary MolarsStudies 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
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 50 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Cairo University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Eithar Musa Abdelrahman Hussien, Cairo University
- Investigators
- Manal Ahmed Elshiekh, prof, PhD, Study director, Cairo University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06890949
- Sponsor's protocol ID
- OW-BFC VS ZRC
- Status last verified
- Mar 2025
- First submitted
- 15 Mar 2025
- Last updated
- 24 Mar 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Rahate I, Fulzele P, Thosar N. Comparative evaluation of clinical performance, child and parental satisfaction of Bioflx, zirconia and stainless steel crowns in pediatric patients. F1000Res. 2023 Dec 21;12:756. doi: 10.12688/f1000research.133464.2. eCollection 2023.
PubMed 38911945
Study at a glance
From the registry record, last updated by the sponsor on 24 Mar 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation Of Occlusal Wear Of Bioflx Crowns Compared To Zirconia Crowns On Primary Molars
- ClinicalTrials.gov ID
- NCT06890949
- Acronym / sponsor ID
- OW-BFC VS ZRC
- Conditions
- Carious Primary Molars
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 50 participants (estimated)
- Lead sponsor
- Cairo UniversityUniversity, hospital or other
- Study start
- 15 Jun 2025 (estimated)
- Primary completion
- 15 Jun 2026 (estimated)
- Study completion
- 16 Jul 2026 (estimated)
- First posted
- 24 Mar 2025 (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.
The goal of this clinical trial is to evaluate the occlusal wear of Bioflx crowns compared to zirconia crowns in the restoration of primary molars.
The main question[s] it aims to answer : " Is there a difference in the occlusal wear of BioFlx crowns compared to zirconia crowns in the restoration of primary molars?" The study will also assess the clinical performance of both types of crowns in terms of retention,gingival health, preparation time, as well as child and parental satisfaction.
Detailed description
Occlusal wear is a critical factor in determining the longevity and functional efficiency of dental restorations, especially in pediatric patients. Primary molars undergo significant masticatory forces, which can lead to material wear and affect the restoration's durability. Bioflex (a relatively new material) and zirconia crowns are commonly used for full-coverage restorations in primary molars, yet there is limited research comparing their occlusal wear characteristics. Understanding how these materials perform under occlusal forces can guide clinicians in selecting the most suitable material for pediatric dental restorations Dental caries in primary molars represent a significant issue within pediatric dentistry. In cases where traditional fillings prove insufficient, full coronal coverage becomes necessary. Stainless steel crowns (SSCs) have long been the standard due to their durability and cost-effectiveness, but their metallic appearance has led to increased interest in aesthetic alternatives like zirconia and Bioflx crowns.
Zirconia offers improved aesthetics, biocompatibility, and mechanical strength, though its long-term clinical performance remains underexplored. While zirconia crowns provide durability and superior aesthetics, they require significant tooth preparation, which may compromise tooth structure. Bioflx crowns, a newer option, combine the benefits of stainless steel and zirconia with more flexibility and less tooth reduction. However, comparative studies on their clinical efficacy, occlusal wear, and patient satisfaction are still needed.
Zirconia offers improved biocompatibility, mechanical strength, and enhanced esthetics, but limited comparative data exists regarding its clinical performance.
The growing awareness among parents regarding the importance of maintaining primary teeth until their natural shedding necessitates a thorough evaluation of the durability, wear resistance, retention, gingival response, and overall clinical efficacy of these crown materials. Zirconia crowns have been the preferred choice for aesthetic restorations due to their natural appearance and durability. However, their requirement for excessive tooth preparation poses challenges in pediatric patients.
Bioflx crowns, made from a biocompatible hybrid resin polymer, offer a flexible fit with minimal tooth reduction while maintaining aesthetic appeal. A comprehensive comparison of occlusal wear between these two materials is crucial for assisting clinicians in selecting the most suitable restorative solution for primary molars. This research seeks to offer evidence-based guidance by evaluating the long-term clinical performance of Bioflx crowns in relation to zirconia crowns.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| (Group A : preformed Bioflx crown | Experimental | Other: (Group A: Preformed Bioflx Crown)Kids-e-Dental LLP (ANDHERI, MUMBAI, INDIA) introduced Bioflx Crowns and claimed as the first flexible, durable, and esthetic preformed crown for primary molars. Bioflx 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 |
| (Group B: Preformed zirconia crown) | Experimental | Other: (Group B: Preformed Zirconia crown)NuSmile 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 seeking a highly esthetic and long-lasting pediatric restoration |
Who may qualify
- Ages
- 4 to 8 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child
Key inclusion criteria (5 listed)
- Children aged between 4 and 8 years with primary molar that needs to be covered by crown.
- Medically healthy children (ASA I or II according to the American Society of Anesthesiologists classification).
- Children whose parent or guardian are 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
Key exclusion criteria (4 listed)
- 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 history of allergies; Known allergies to dental local anesthesia or to the materials used in Bioflx crowns.
- Children with any systemic conditions or disabilities that may affect their ability to participate in the study.
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 |
|---|---|---|
| (Group A: Preformed Bioflx Crown)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. Tooth Preparation 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. | Other | (Group A : preformed Bioflx crown |
| (Group B: Preformed Zirconia crown)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 crown that closely matches the measured 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 using a tapered fissure bur. Crown Placement \& Passive Fit Check Place the selected crown and check for passive fit. 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 proper seating. Final Adjustments \& Cleanup Remove excess cement using floss or an explorer. Verify fit, occlusion, and stability | Other | (Group B: Preformed zirconia crown) |
Primary outcome
Occlusal wear of crown
Time frame: T (Time): 12months interval T0: 0 T1: 3 month T2: 6month T3: 12 month]
Measure by Modified United States Public Health System criteria: Alpha: Occlusal surface intact. Bravo: Wear of occlusal surface without tooth surface exposure Charlie: Wear of occlusal surface with exposure
4 secondary outcomes
Retention
Time frame: [Time Frame: follow-up:T (Time): 12months interval T0: 0 T1: 3month T2: 6month T3 : 12 month]
Gingival Health
Time frame: T (Time): 12 months interval T0: 0 T1: 3month T2: 6month T3 : 12 month]
preparation time
Time frame: [Time Frame: baseline]
child and parental satisfaction
Time frame: [Time Frame: T (Time): 12months interval T0: 0 T1: 3 month T2: 6month T3: 12 month]
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 24 Mar 2025.
- Background: PubMed 38911945Rahate I, Fulzele P, Thosar N. Comparative evaluation of clinical performance, child and parental satisfaction of Bioflx, zirconia and stainless steel crowns in pediatric patients. F1000Res. 2023 Dec 21;12:756. doi: 10.12688/f1000research.133464.2. eCollection 2023.
- Individual participant dataSharing planned: No
Related trials for Carious Primary Molars
Not yet recruiting
Clinical and Radiographic Evaluation of Silver Diamine Fluoride Versus Light-Cured Silver Diamine Fluoride in Carious Primary Molars
Dental Caries
Not yet recruiting
Clinical and Radiographic Comparison of SMART Hall and Conventional Hall Techniques in Children With Carious Primary Molars
Clinical Effect
Not yet recruiting
Oxymetazoline Versus Sodium Hypochlorite as Hemostatic Agents in MTA Pulpotomy of Primary Molars
Pulp Disease, Dental, Pulp Therapy in Primary Molars
Recruiting
A Study Comparing the Hall Technique and Conventional Stainless-Steel Crowns in Carious Primary Molars : Clinical Outcomes, Anxiety, Time, and Cost-Effectiveness
Hall Technique
Not yet recruiting
Pain Perception of Novel Chemo-mechanical Caries Remove Versus Atraumatic Restorative Treatment Method in Primary Molars
Carious Primary Molars
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.
Eithar musa Abdelrahman Hussion, Bachelor of dental science contact
Manal Ahmed Elshiekh, prof, PhD study director
Cairo University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing (Group A: Preformed Bioflx Crown) and (Group B: Preformed 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 24 Mar 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 Eithar musa Abdelrahman Hussion, Bachelor of dental science (00201098801323, Eithar.musa55@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Occlusal wear of crown (time frame: T (Time): 12months interval T0: 0 T1: 3 month T2: 6month T3: 12 month]). 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 NCT06890949, which also lists 1 linked publication.
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 24 Mar 2025.