BioFlex Crowns Using Hall TechniqueNCT06847646
Evaluation of Bioflex Crowns Using the Hall Technique in Primary Molars
A study testing bioflex crown using hall technique and stainless steel crown using hall technique in people with BioFlex Crowns Using Hall Technique, run by Alexandria University at 1 site in Egypt.
Trial summary
The goal of this randomized controlled clinical trial is to to evaluate the clinical performance and radiographic success of BioFlex crowns versus SSCs using Hall Technique in primary dentition. Read more about this study
- Who is it for?
- Ages 4 to 7 years
- Conditions the study is for
- BioFlex Crowns Using Hall Technique
- What is being tested?
- bioflex crown using hall technique and stainless steel crown using hall technique
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 74 participants
- Where
- 1 siteEgypt
- Study dates
- 20 Aug 2024to 20 Aug 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
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 7 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Primary molar teeth with occlusal or occlusoproximal carious lesions into dentin (ICDAS codes: 3-5).
Who cannot join
- Clinical or radiographic signs of irreversible pulpitis.
- Presence of fistula or abscess.
- Spontaneous pain.
- Pulp exposure.
- Bruxism.
- Pathologic mobility (identified by gently rocking the tooth buccolingually using tweezers).
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Evaluation of Bioflex Crowns Using the Hall Technique in Primary Molars (a Randomized Controlled Clinical Trial)
The goal of this randomized controlled clinical trial is to to evaluate the clinical performance and radiographic success of BioFlex crowns versus SSCs using Hall Technique in primary dentition. The main questions it aims to answer are:
Does bioflex crowns have the same clinical performance and radiographic success of stainless steel crowns when placed using Hall Technique?
Read more
will bioflex crowns alter the occlusal vertical dimensions or affect the tempomandibular joint?
If there is a comparison group: Researchers will compare bioflex crown to stainless steel crown to see of the bioflex crowns are effective as stainless steel crowns when placed using hall technique
Participants will recieve bioflex crown and stainless steel crown according to randomization and they will be followed up immediately after treatment, after 2 weeks , after 1 months , after 3 months , after 6 months and after 12 months
Read the detailed description
The study will be a double-armed randomized controlled clinical trial, with parallel design. A total of 74 pediatric patients aged 4-8 years will be selected from the Pediatric Dentistry Outpatient Clinic, Faculty of Dentistry, Alexandria University, Egypt. Participants will be allocated into 2 groups according to the type of crown used. Group I (study group) will be treated with BioFlex crowns using Hall technique, while Group II (control group) will be treated with the SSCs using Hall technique. Clinical and radiographic success of both crowns will be assessed. The function of the temporomandibular joint (TMJ) will be evaluated using the Helkimo Clinical Dysfunction Index (Di) and the AAPD questionnaire. The Occlusovertical dimension measurements will also be evaluated using the Van der Zee and Van Amerongen method. Plaque and gingival health will be recorded using plaque and gingival indices, and the satisfaction level of the child will be assessed using the Facial Image Scale (FIS), while the satisfaction level of parents will be assessed using questionnaire.
- Conditions
- BioFlex Crowns Using Hall Technique
- Being tested
- bioflex crown using hall technique, stainless steel crown using hall technique
- Keywords
- BioFlex crowns, SSCs, Hall technique, TMJ function
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
bioflex crown using hall techniqueOther
crowns assessment
stainless steel crown using hall techniqueOther
crown assessment
| Study group | Role | What they receive |
|---|---|---|
| bioflex crown using hall technique | Experimental | bioflex crown using the hall technique Receives: Other: bioflex crown using hall technique |
| stainless steel crowns using hall technique | Active comparator | stainless steel crown using the hall technique Receives: Other: stainless steel crown using hall technique |
What is being measured
The primary outcome is the main question the study is designed to answer.
To evaluate the clinical performance of BioFlex crowns versus SSCs using HT.
clinical evaluation of crown performance
Success:
- Satisfactory restoration/crown, no intervention required
- No clinical signs or symptoms of pulp pathology
Minor Failures:
- Crown presents perforation
- Crown loss - tooth able to be re-treated
Major Failures:
- Reversible or irreversible pulpitis or dental fistula/abscess, requiring pulpotomy, pulpectomy or extraction.
Measured: 12 months
To evaluate the radiographic success of BioFlex crowns versus SSCs using HT.
radiographic evaluation using digital xrays
- Teeth will be considered radiographically successful if they show no evidence of:
- Radicular radiolucency
- Internal or external root resorption
- Periodontal ligament space widening
Measured: 12 months
Secondary outcomes (6)
Temporomandibular joint function assessment
The Helkimo Clinical Dysfunction Index (modified version) assesses TMJ dysfunction based on:
Maximum Opening:
0 = ≥35 mm
- = 25-34 mm
- = <25 mm
Deflection During Opening:
0 = <2 mm
- = 2-5 mm
- = >5 mm
Impaired TMJ Function:
0 = no impairment
- = palpable click
- = audible click, deadlock, or luxation
Pain in TMJ:
0 = no pain
- = palpable pain
- = reflex pain
Muscle Pain (Temporalis \& Masseter):
0 = no pain
- = palpable pain
- = reflex pain
Score Classification:
0 = no dysfunction 1-4 = mild dysfunction 5-9 = moderate dysfunction 9 = serious dysfunction
The AAPD guidelines are used for assessing TMJ symptoms, asking about difficulty opening the mouth, pain, muscle pain in the temporalis and masseter, sounds, and jaw-related injuries. Responses are yes/no.
Measured: 6 months
Changes in the occlusal vertical dimensions
The assessment of the OVD will be performed according to a Modified version of van der Zee and van Amerongen method The cusp tip of the left maxillary canine was marked using a pencil on the lower canine in the maximum intercuspation, and its distance to the mandibular canine cusp tip was measured using a UNC-15 probe and used as the overbite score
Measured: 1 month
Dental plaque assessment
Criteria for scoring plaque index (Silness and Löe)
0 No plaque
- A film of plaque adhering to the free gingival margin and adjacent area of the tooth. The plaque may only be recognized by running a probe across the tooth surface.
- Moderate accumulation of soft deposits within the gingival pockets or the tooth and gingival margin which can be seen with the naked eye.
- Abundance of soft matter within the gingival pocket and /or on the tooth and gingival margin.
Measured: 12 months
gingival health assessment
Criteria for scoring gingival index (Löe and Silness) 0 Healthy (No gingivitis.).
- Mild gingivitis, Slight redness and edema, no bleeding upon probing
- Moderate gingivitis, moderate redness and edema, bleeding upon probing
- Severe gingivitis, severe redness and edema, spontaneous bleeding and ulcerations
Measured: 12 months
Parental satisfaction assessment
- The satisfaction level of parent/legal guardian will be assessed as performed immediately post-operative, in addition to problems that the child might be facing, such as bleeding around the crown, sensitivity, and food lodgment using questionnaire Parental satisfaction will be assessed on a Likert type scale from 1 to 5 using the seven following variables: shade, size, shape, retention, durability, overall satisfaction, and child's satisfaction.
Measured: 12 months
child satisfaction assessment
- The patient's perception of the treatment will be assessed by using the Facial Image Scale (FIS) modified from the Maunuksela et al scale
- Very happy.
- Happy.
- Neutral.
- Sad.
- Very sad.
Measured: immediately after treatment
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted26 Feb 2025
- Study start20 Aug 2024
- Primary completion20 Aug 2025
- Study completion20 Aug 2025
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 BioFlex Crowns Using Hall TechniqueStudies of the same condition, open and under way.
- More trials run by Alexandria 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
- Model description
- The study was a two arm, parallel group, randomized controlled clinical trial. Allocation ratio is intended to be 1:1.
- Masking
- None (open label)
- Enrolment
- 74 participants (actual)
Sponsor and investigators
- Lead sponsor
- Alexandria University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Yousra Ramadan, Alexandria University
- Investigators
- yousra ramadan, Ms, Principal investigator, Alexandria University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06847646
- Sponsor's protocol ID
- 0931-06/2024
- Status last verified
- Dec 2025
- First submitted
- 19 Feb 2025
- Last updated
- 18 Dec 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Publications
Ramadan Y, Baraka M, Dean JA, Wahba NA. Clinical and radiographic success of bioflex versus stainless steel crowns using the hall technique in primary molars: a 12-month randomized controlled trial. Clin Oral Investig. 2026 Oct 22;30(11):544. doi: 10.1007/s00784-026-07156-4.
PubMed 42911278
Study at a glance
From the registry record, last updated by the sponsor on 18 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of Bioflex Crowns Using the Hall Technique in Primary Molars (a Randomized Controlled Clinical Trial)
- ClinicalTrials.gov ID
- NCT06847646
- Acronym / sponsor ID
- 0931-06/2024
- Conditions
- BioFlex Crowns Using Hall Technique
- Keywords
- BioFlex crowns, SSCs, Hall technique, TMJ function
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 74 participants (actual)
- Lead sponsor
- Alexandria UniversityUniversity, hospital or other
- Study start
- 20 Aug 2024 (actual)
- Primary completion
- 20 Aug 2025 (actual)
- Study completion
- 20 Aug 2025 (actual)
- First posted
- 26 Feb 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 randomized controlled clinical trial is to to evaluate the clinical performance and radiographic success of BioFlex crowns versus SSCs using Hall Technique in primary dentition. The main questions it aims to answer are:
Does bioflex crowns have the same clinical performance and radiographic success of stainless steel crowns when placed using Hall Technique?
will bioflex crowns alter the occlusal vertical dimensions or affect the tempomandibular joint?
If there is a comparison group: Researchers will compare bioflex crown to stainless steel crown to see of the bioflex crowns are effective as stainless steel crowns when placed using hall technique
Participants will recieve bioflex crown and stainless steel crown according to randomization and they will be followed up immediately after treatment, after 2 weeks , after 1 months , after 3 months , after 6 months and after 12 months
Detailed description
The study will be a double-armed randomized controlled clinical trial, with parallel design. A total of 74 pediatric patients aged 4-8 years will be selected from the Pediatric Dentistry Outpatient Clinic, Faculty of Dentistry, Alexandria University, Egypt. Participants will be allocated into 2 groups according to the type of crown used. Group I (study group) will be treated with BioFlex crowns using Hall technique, while Group II (control group) will be treated with the SSCs using Hall technique. Clinical and radiographic success of both crowns will be assessed. The function of the temporomandibular joint (TMJ) will be evaluated using the Helkimo Clinical Dysfunction Index (Di) and the AAPD questionnaire. The Occlusovertical dimension measurements will also be evaluated using the Van der Zee and Van Amerongen method. Plaque and gingival health will be recorded using plaque and gingival indices, and the satisfaction level of the child will be assessed using the Facial Image Scale (FIS), while the satisfaction level of parents will be assessed using questionnaire.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- The study was a two arm, parallel group, randomized controlled clinical trial. Allocation ratio is intended to be 1:1.
| Arm | Type | Receives |
|---|---|---|
| bioflex crown using hall technique | Experimental | Other: bioflex crown using hall techniquebioflex crown using the hall technique |
| stainless steel crowns using hall technique | Active comparator | Other: stainless steel crown using hall techniquestainless steel crown using the hall technique |
Who may qualify
- Ages
- 4 to 7 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (1 listed)
- Primary molar teeth with occlusal or occlusoproximal carious lesions into dentin (ICDAS codes: 3-5).
Key exclusion criteria (6 listed)
- Clinical or radiographic signs of irreversible pulpitis.
- Presence of fistula or abscess.
- Spontaneous pain.
- Pulp exposure.
- Bruxism.
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 |
|---|---|---|
| bioflex crown using hall techniquecrowns assessment | Other | bioflex crown using hall technique |
| stainless steel crown using hall techniquecrown assessment | Other | stainless steel crowns using hall technique |
Primary outcome
To evaluate the clinical performance of BioFlex crowns versus SSCs using HT.
Time frame: 12 months
clinical evaluation of crown performance Success: * Satisfactory restoration/crown, no intervention required * No clinical signs or symptoms of pulp pathology Minor Failures: * Crown presents perforation * Crown loss - tooth able to be re-treated Major Failures: • Reversible or irreversible pulpitis or dental fistula/abscess, requiring pulpotomy, pulpectomy or extraction.
To evaluate the radiographic success of BioFlex crowns versus SSCs using HT.
Time frame: 12 months
radiographic evaluation using digital xrays • Teeth will be considered radiographically successful if they show no evidence of: 1. Radicular radiolucency 2. Internal or external root resorption 3. Periodontal ligament space widening
6 secondary outcomes
Temporomandibular joint function assessment
Time frame: 6 months
Changes in the occlusal vertical dimensions
Time frame: 1 month
Dental plaque assessment
Time frame: 12 months
gingival health assessment
Time frame: 12 months
Parental satisfaction assessment
Time frame: 12 months
child satisfaction assessment
Time frame: immediately after treatment
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Dec 2025.
- Derived from this study: PubMed 42911278Ramadan Y, Baraka M, Dean JA, Wahba NA. Clinical and radiographic success of bioflex versus stainless steel crowns using the hall technique in primary molars: a 12-month randomized controlled trial. Clin Oral Investig. 2026 Oct 22;30(11):544. doi: 10.1007/s00784-026-07156-4.
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.
yousra ramadan, Ms principal investigator
Alexandria 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 bioflex crown using hall technique and stainless steel crown using hall technique in people with BioFlex Crowns Using Hall Technique, run by Alexandria 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 1 inclusion and 6 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: finished, as of the sponsor's last update on 18 Dec 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
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?
To evaluate the clinical performance of BioFlex crowns versus SSCs using HT. (time frame: 12 months). The study lists 2 primary outcomes in all. 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 NCT06847646, 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 18 Dec 2025.