Retention of Bioflx Crowns Compared to Zirconia Crowns on Primary Molars

NCT ID: NCT06856070

Last Updated: 2025-03-04

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 50 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-06-30
• Study Completion Date: 2026-02-28

Brief Summary

The goal of this clinical trial is to evaluate the retention and resistance to dislodgment 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 retention and resistance to dislodgement 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 occlusal wear, gingival health, preparation time, as well as child and parental satisfaction.

Detailed Description

Primary molars play a significant role in maintaining oral function, esthetics, and space for permanent teeth, therefore, restoring decayed primary molars is a critical aspect of pediatric dentistry. Stainless steel crowns have been the standard restorative material for primary molars due to their clinical success, retention, and durability. However, the aesthetic limitations of SSCs, have been problematic, especially when patients seek more esthetically acceptable treatment options.In an attempt to address the aesthetic limitations of stainless-steel crowns, pre-veneered stainless-steel crowns were introduced featuring a thin layer of composite resin or ceramic on the outside to improve their appearance. While they provided a better aesthetic than pure stainless steel, their limitations included a tendency to wear down over time, difficulty in matching natural tooth color, and the potential for the veneer to chip or detach.Recently, zirconia crowns are preferred over pre-veneered stainless-steel crowns for their esthetic superiority, biocompatibility, and resistance to wear. They demonstrate excellent retention and durability but require significant tooth preparation, which may compromise tooth structure. Despite their advantages, zirconia crowns posed challenges such as increased cost, more complex preparation techniques, and concerns about their brittleness under certain conditions. Moreover, zirconia crowns may not be suitable for all cases, especially those involving less mineralized or structurally compromised primary molars .In 2021, Kids-e-Dental LLP 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.

It is important to mention that retention is a crucial factor for the success of any dental crown. An inadequate retention can lead to crown displacement, necessitating re-treatment, and ultimately affect the long-term health of the primary tooth. While studies have demonstrated the superior esthetic properties of materials like Bioflx crowns, their clinical performance, particularly retention rates and overall longevity, require further evaluation in direct comparison to zirconia crowns .Thus, this trial aims to fill the gap in current knowledge and provide clinicians with evidence to support the choice of crown material based on retention performance, which is critical to the long-term success of pediatric restorations.

Conditions

Carious Primary Molars

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

(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 Type: EXPERIMENTAL

(Group A: Preformed Bioflx crown)

Intervention Type: OTHER

prepartion:1.The mesiodistal width of the tooth will be measured using calipers and a closely fitted crown will be selected based on the measurements.

2. The tooth will be prepared similarly to stainless steel crowns (SSCs):

• Occlusal reduction of approximately 1-1.5 mm will be done using a diamond bur.Mesial and distal reduction of no more than 1 mm will be performed using a No. 169L diamond bur.Depending on the tooth anatomy, either no buccal and lingual reduction will be needed, or a minimal reduction will be done.

3.All sharp line angles and corners will be smoothed to ensure proper crown fit.

4.The crown will be checked for proper fit before cementation. It will be positioned to extend 1 mm below the gingival margin.

5.The crown will be cemented using luting glass ionomer cement (GIC). The crown will be held with firm, constant pressure until the cement sets initially.

6.The marginal fit will be evaluated, and necessary adjustments will be made. 7.The occlusion will be checked,

(Group B: Preformed zirconia crown)

Zirconia crowns have been widely used in pediatric dentistry due to their high esthetic value, biocompatibility, and strength. Studies have shown that zirconia crowns exhibit superior retention due to their passive fit and resistance to fracture.

Group Type: EXPERIMENTAL

(Group B: Preformed Zirconia crown)

Intervention Type: OTHER

1\. Crown Selection: The mesiodistal dimension of the corresponding tooth will be measured . to select the appropriate size.2. Occlusal Reduction: The marginal ridge of adjacent teeth will be used as a reference point and a 1.5-2 mm of occlusal reduction will be performed to allow proper crown seating.3. Bucco-Lingual Reduction: The bucco-lingual wall will be reduced by approximately 1-1.5 mm using a flame-shaped diamond bur.4. Interproximal Reduction: 1 mm of interproximal reduction will be performed using a flame-shaped diamond bur such as a .368 or .330 tapered carbide bur.5. Feather Margin Preparation: Subgingival reduction of 1-2 mm will be done using a flame-shaped diamond bur, creating a feathered margin to achieve a passive fit.6. Trial Fitting of the Crown: The crown will be tried in to ensure proper adaptation. until the crown fits passively and extends sub gingivally by 1-2 mm wit.7. Glass ionomer cement will be used for cementation.

Interventions

(Group A: Preformed Bioflx crown)

prepartion:1.The mesiodistal width of the tooth will be measured using calipers and a closely fitted crown will be selected based on the measurements.

2. The tooth will be prepared similarly to stainless steel crowns (SSCs):

• Occlusal reduction of approximately 1-1.5 mm will be done using a diamond bur.Mesial and distal reduction of no more than 1 mm will be performed using a No. 169L diamond bur.Depending on the tooth anatomy, either no buccal and lingual reduction will be needed, or a minimal reduction will be done.

3.All sharp line angles and corners will be smoothed to ensure proper crown fit.

4.The crown will be checked for proper fit before cementation. It will be positioned to extend 1 mm below the gingival margin.

5.The crown will be cemented using luting glass ionomer cement (GIC). The crown will be held with firm, constant pressure until the cement sets initially.

6.The marginal fit will be evaluated, and necessary adjustments will be made. 7.The occlusion will be checked,

Intervention Type: OTHER

(Group B: Preformed Zirconia crown)

1\. Crown Selection: The mesiodistal dimension of the corresponding tooth will be measured . to select the appropriate size.2. Occlusal Reduction: The marginal ridge of adjacent teeth will be used as a reference point and a 1.5-2 mm of occlusal reduction will be performed to allow proper crown seating.3. Bucco-Lingual Reduction: The bucco-lingual wall will be reduced by approximately 1-1.5 mm using a flame-shaped diamond bur.4. Interproximal Reduction: 1 mm of interproximal reduction will be performed using a flame-shaped diamond bur such as a .368 or .330 tapered carbide bur.5. Feather Margin Preparation: Subgingival reduction of 1-2 mm will be done using a flame-shaped diamond bur, creating a feathered margin to achieve a passive fit.6. Trial Fitting of the Crown: The crown will be tried in to ensure proper adaptation. until the crown fits passively and extends sub gingivally by 1-2 mm wit.7. Glass ionomer cement will be used for cementation.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

1. Children aged between 4 and 8 years with primary molar that needs to be covered by crown.

2. Children who can cooperate sufficiently for the duration of the procedure, as assessed by behavior management techniques.

3. Medically healthy children (ASA I or II according to the American Society of Anesthesiologists classification).

4. Children whose parent or guardian are willing to sign an informed consent.

5. Children whose parent or guardian are willing to comply with follow-up visits. -

Exclusion Criteria

1. Molars with severe structural loss that may compromise crown retention.

2. Children with poor oral hygiene that may contribute to higher plaque levels and affect the clinical outcomes of the crown restorations.

3. Children with history of allergies; Known allergies to dental local anesthesia or to the materials used in Bioflx crowns.

4. Children with any systemic conditions or disabilities that may affect their ability to participate in the study.

• Minimum Eligible Age: 4 Years
• Maximum Eligible Age: 8 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Cairo University

OTHER

Sponsor Role: lead

Responsible Party

noura jamal elnoor mohamed

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Dr.manal ahmed elshiekh Prof, Ph.D

Role: STUDY_DIRECTOR

Cairo University

Locations

Faculty of Dentistry, Cairo University.

Cairo, Giza Governorate, Egypt

Faculty of Dentistry, Cairo University.

Cairo, , Egypt

Countries

Egypt

Central Contacts

noura jamal elnoor mohamed, bachelor of dental science

Role: CONTACT

nourajamal997@gmail.com

00201148788374

Facility Contacts

noura jamal elnoor mohamed, B.DSc

Role: primary

nourajamal997@gmail.com

00201148788375

References

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.

Reference Type: BACKGROUND

PMID: 38911945 (View on PubMed)

Patil AS, Jain M, Choubey S, Patil M, Chunawala Y. Comparative evaluation of clinical success of Stainless Steel and Bioflx crowns in primary molar - A 12 month split mouth prospective randomized clinical trial. J Indian Soc Pedod Prev Dent. 2024 Jan 1;42(1):37-45. doi: 10.4103/JISPPD.JISPPD_484_23. Epub 2024 Apr 15.

Reference Type: BACKGROUND

PMID: 38616425 (View on PubMed)

Other Identifiers

RR-BFC Vs ZR

Identifier Type: -

Identifier Source: org_study_id