Vertical Dimension Changes After Bioflx vs Stainless Steel Crowns in Primary Molars (BIOFLX-SSC-RCT)

April 6, 2026 updated by: Eman Adel Osman Hassan, Cairo University

Vertical Dimension Changes and Mean Biting Force Following Bioflx Placement Over Pulp-treated Primary Molars Versus Stainless Steel Crowns: A Randomized Controlled Trial.

this randomized controlled trial will compare Bioflx crowns and stainless-steel crowns in children with pulp-treated primary molars. The study will evaluate changes in vertical dimension and mean biting force after crown placement and will also assess parental satisfaction with esthetics and treatment impact. Eligible children aged 6 to 9 years will be randomly assigned in a 1:1 ratio to receive either a Bioflx crown or a stainless-steel crown. Measurements will be taken at baseline, immediately after crown placement, at 1 week, and at 4 weeks.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

Early childhood caries commonly affects primary molars and often requires full-coverage restoration after pulp therapy. Stainless steel crowns are widely used because of their durability and clinical success, but they may have limitations related to esthetics and acceptance. Bioflx crowns are a more esthetic and flexible alternative, but there is limited evidence comparing their functional performance with stainless steel crowns.

This parallel randomized controlled trial will be conducted at the outpatient clinic of Pediatric Dentistry and Dental Public Health, Faculty of Dentistry, Cairo University, Egypt. A total of 18 children with pulp-treated primary molars will be enrolled and randomly allocated in a 1:1 ratio to receive either a Bioflx crown or a stainless steel crown.

The primary outcome is vertical dimension alteration measured in millimetres using a digital caliper. Secondary outcomes include mean biting force distribution measured by T-Scan digital occlusal analysis, parental satisfaction with esthetics, and parental satisfaction with treatment impact assessed by 5-point Likert scale questionnaires. Outcome measurements will be recorded at baseline, immediately after crown placement, at 1 week, and at 4 weeks, with parental satisfaction assessed at 4 weeks.

The purpose of this study is to determine whether Bioflx crowns provide comparable or improved functional and esthetic outcomes compared with stainless steel crowns in pulp-treated primary molars.

Study Type

Interventional

Enrollment (Estimated)

18

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

  • Egypt
    • Giza/Egypt
      • Cairo, Giza/Egypt, Egypt, 12613
        • Cairo University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Pulp-treated primary molars (pulpotomy)

    • Asymptomatic teeth after pulp therapy with no signs of infection, mobility, or radiographic pathology, such as internal resorption or periapical lesions
    • Age 6 years to 9 years
    • Male or female
    • Cooperative child with positive Frankl behavior rating
    • No missing teeth
    • Normal occlusion, including normal overjet and overbite
    • Free from systemic disease to allow continuity of follow-up

Exclusion Criteria:

  • Medically compromised or uncooperative children

    • Tooth indicated for extraction because of root resorption, teeth near exfoliation, or deep subgingival caries that prevents proper coronal seal
    • Teeth with more than two-thirds root resorption
    • Previous pulp therapy
    • Parafunctional habits, including bruxism, thumb-sucking, or other habits that may affect occlusal force measurements
    • Inability to attend follow-up visits or parental refusal to participate

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Bioflx Crown Group
Participants in this arm will receive Bioflx crowns after pulp therapy of primary molars. Crown placement will follow the study protocol, and outcomes including vertical dimension, mean biting force, and parental satisfaction will be assessed during follow-up.
Device: Bioflx Crown
Aesthetic full-coverage pediatric crown used after pulp therapy of primary molars. The Bioflx crown will be selected according to tooth size, adapted following the study protocol, and cemented with resin-modified glass ionomer cement.
Active Comparator: Stainless Steel Crown Group
Participants in this arm will receive stainless steel crowns after pulp therapy of primary molars. Crown placement will follow the study protocol, and outcomes including vertical dimension, mean biting force, and parental satisfaction will be assessed during follow-up.
Device: Stainless Steel Crown
Preformed stainless steel full-coverage pediatric crown used after pulp therapy of primary molars. The stainless steel crown will be selected according to tooth size, adapted following the study protocol, and cemented with resin-modified glass ionomer cement

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Vertical dimension alterations
Time Frame: Baseline, immediately after crown placement, 1 week, and 4 weeks
Change in inter-occlusal vertical dimension measured in millimetres using a digital caliper at baseline, immediately after crown placement, at 1 week, and at 4 weeks. Mean differences will be compared between the Bioflx crown group and the stainless steel crown group.
Baseline, immediately after crown placement, 1 week, and 4 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Mean Biting Force Distribution
Time Frame: Baseline, immediately after crown placement, 1 week, and 4 weeks
Occlusal force distribution on the restored tooth measured as a percentage using T-Scan digital occlusal analysis at baseline, immediately after crown placement, at 1 week, and at 4 weeks. Force distribution will be compared between the Bioflx crown group and the stainless steel crown group.
Baseline, immediately after crown placement, 1 week, and 4 weeks
Parental Satisfaction With Treatment Impact
Time Frame: 4 weeks
Parental ratings of the impact of treatment on the child, including comfort, chewing ability, well-being, and perceived improvement in appearance, assessed using a 5-point Likert scale questionnaire.
4 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Cairo University

Investigators

  • Principal Investigator: Osama A El shahawy, PHD, Cairo University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

  • Almajed OS. Shaping Smiles: A Narrative Review of Crown Advancements in Pediatric Dentistry. Cureus. 2024;16(1):e52997. doi:10.7759/cureus.52997.
  • Mathew MG, Roopa KB, Soni AJ, Khan MM, Kauser A. Evaluation of clinical success, parental and child satisfaction of stainless-steel crowns and zirconia crowns in primary molars. J Family Med Prim Care. 2020 Mar 26;9(3):1418-1423. doi:10.4103/jfmpc.jfmpc_1006_19.
  • 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.
  • Maheshkumar K, Chowdhary N, Chowdharry R, Vundela RR, Sonnahalli NK, Anuraaga AT. Bite force evaluation at maximal intercuspal position: An in vivo comparative study between stainless steel and zirconia crowns on primary molar teeth. J Indian Soc Pedod Prev Dent. 2023 Apr-Jun;41(2):89-97. doi:10.4103/jisppd.jisppd_156_23.
  • Nair K, Chikkanarasaiah N, Poovani S, Thumati P. Digital occlusal analysis of vertical dimension and maximum intercuspal position after placement of stainless steel crown using Hall technique in children. Int J Paediatr Dent. 2020 Nov;30(6):805-815. doi:10.1111/ipd.12647.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

April 1, 2026

Primary Completion (Estimated)

August 1, 2026

Study Completion (Estimated)

August 1, 2026

Study Registration Dates

First Submitted

April 6, 2026

First Submitted That Met QC Criteria

April 6, 2026

First Posted (Actual)

April 13, 2026

Study Record Updates

Last Update Posted (Actual)

April 13, 2026

Last Update Submitted That Met QC Criteria

April 6, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • CU-PD-2025-001

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared. The study involves a small sample of pediatric participants, and data confidentiality and participant privacy will be protected according to institutional and ethical requirements.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Dental Caries

Clinical Trials on Bioflx Crown

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Switzerland

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe