Clinical Outcomes and Satisfaction of Stainless Steel vs Bioflx Crowns in Primary Molars

NCT07357402 | Active Not Recruiting DMC FDA Device

• 1 other identifier: 3526/QĐ-ĐHYD
• Study Type: interventional
• Target: 25
• Locations: 1 country
• Sites: 2

Brief Summary

The goal of this clinical trial is to learn if the Bioflx crown (a tooth-colored material) is as effective as the standard stainless steel crown for treating severely decayed baby back teeth in children aged 4 to 10 years old. The study also aims to evaluate parent and child satisfaction with these restorative options. The main questions it aims to answer are:

1. 1.Is the Bioflx crown as effective as the stainless steel crown in terms of durability, staying in place, and protecting the tooth from new decay?
2. 2.Does the Bioflx crown maintain better gum health and cause less wear on the opposing teeth compared to the stainless steel crown?
3. 3.Receive one Bioflx crown and one stainless steel crown on similar teeth on opposite sides of the mouth.
4. 4.Visit the clinic for two separate appointments, spaced 1 to 2 weeks apart, to have the crowns placed.
5. 5.Return for checkups at 3 months and 6 months so researchers can examine the health of the teeth and gums.
6. 6.Answer questions about how happy they are with the appearance and feel of the crowns.

Conditions

Severely Decayed Primary Molars Requiring Full-Coverage Crowns

Keywords

Stainless steel crowns; Bioflx crowns; Primary molars; Split-mouth study; Parental and child satisfaction

Outcome Measures

Primary Outcomes (1)

• - Clincal outcomes: crown stability; bite discomfort; fit and color changes at the crown edge; crown shape; crown retention; crown wear; wear of the opposing tooth or crown - Oral hygiene and gum health around the crowns

  * Each clinical parameter was assessed using the modified United States Public Health Service (USPHS) criteria. * Outcomes were rated on a three-level scale (Alpha, Bravo, Charlie), where Alpha indicates an ideal condition, Bravo an acceptable condition with minor defects, and Charlie an unacceptable condition requiring repair or replacement. For analysis, Alpha and Bravo scores were considered acceptable, while Charlie scores were considered failures. * Secondary caries were assessed using periapical radiographs, while all other clinical parameters were assessed by dental explorer and documented using photographs (Canon 6D camera). * This outcome evaluates how clean the teeth are and how healthy the gums are around crowned teeth. Plaque and gum condition were evaluated using standard dental indices (Plaque Index and Gingival Index). Dentists exam by using a periodontal probe at six points around the crowns, and the scores were combined to provide an overall result.

  - Crown stability, bite discomfort, fit and color at the crown margin, and crown shape were checked after crown placement, at 3 months, and at 6 months follow-up visits. Others were checked at 3, 6 months, except secondary caries was checked at 6 months

Secondary Outcomes (1)

• parent and child satisfaction

  From immediately after crowns placement through the 3-month and 6-month follow-up visits.

Study Arms (2)

Stainless steel crown

ACTIVE COMPARATOR

Participants receive a prefabricated stainless steel crown placed on a primary molar according to standard pediatric dental procedures. The crown is selected, adapted, and cemented following conventional clinical protocols and serves as the standard treatment comparator in this study.

Device: Stainless Steel Crown

Bioflx crown

EXPERIMENTAL

Participants receive a prefabricated Bioflx crown placed on a primary molar using manufacturer-recommended techniques. The crown is selected and cemented following standardized clinical procedures and is evaluated as the experimental intervention for clinical performance and patient-related outcomes.

Device: Bioflx crown

Interventions

Bioflx crown DEVICE

Bioflx crowns are prefabricated tooth-colored polymer crowns designed to improve esthetics compared with conventional stainless steel crowns

Bioflx crown

Stainless Steel Crown DEVICE

Stainless steel crowns are prefabricated metal crowns that have been widely and long used in pediatric dentistry to restore primary molars with extensive caries or following pulp therapy.

Stainless steel crown

Eligibility Criteria

• Age: 4 Years - 10 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• Children with at least two carious primary molars located on both the right and left sides of the dental arch and indicated for crown placement
• Children and their parents have ability to communicate in Vietnamese
• Primary molars indicated for full-coverage crown restoration, including teeth with:
• Multi-surface caries
• Extensive caries or enamel-dentin defects
• Interproximal caries
• High risk of failure with other restorative materials
• Teeth following pulpotomy or pulpectomy

You may not qualify if:

• Uncooperative children
• Presence of psychiatric or neurological disorders affecting communication ability
• Malocclusion (crossbite or scissors bite)
• Having abnormal parafunctional habits
• Teeth with root resorption exceeding one half of the root length

Sponsors & Collaborators

• PHAM LE ANH THY: lead

Study Sites (2)

University of Medicine and Pharmacy at Ho Chi Minh City

Ho Chi Minh City, 700000, Vietnam

Location

University of Medicine and Pharmacy at Ho Chi Minh City

Ho Chi Minh City, Vietnam

Location

Related Publications (5)

• Tin BT, Phuong NTM, Anh NTH, Bau TH, Dong TT, Ngoc VTN. Short-Term Clinical Evaluation of Bioflx Crowns for Primary Molar Restoration in Children Aged 4-8 Years in Vietnam: A Pilot Observational Study. Int J Paediatr Dent. 2026 Jan;36(1):187-194. doi: 10.1111/ipd.70039. Epub 2025 Oct 22.

  PMID: 41126408 BACKGROUND

• 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. eCollection 2020 Mar.

  PMID: 32509626 BACKGROUND

• Lopez-Cazaux S, Aiem E, Velly AM, Muller-Bolla M. Preformed pediatric zirconia crown versus preformed pediatric metal crown: study protocol for a randomized clinical trial. Trials. 2019 Aug 24;20(1):530. doi: 10.1186/s13063-019-3559-1.

  PMID: 31445509 BACKGROUND

• Pozos-Guillen A, Chavarria-Bolanos D, Garrocho-Rangel A. Split-mouth design in Paediatric Dentistry clinical trials. Eur J Paediatr Dent. 2017 Mar;18(1):61-65. doi: 10.23804/ejpd.2017.18.01.13.

  PMID: 28494606 BACKGROUND

• 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.

  PMID: 38616425 BACKGROUND

Study Officials

• Huong Thi Nguyen Nguyen, PhD

  Faculty of Dentistry, University of Medicine and Pharmacy at Ho Chi Minh City

  STUDY CHAIR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Dentist

Model Details: The study is designed as a randomized split-mouth clinical trial. Each child will receive both types of crowns on two similar teeth on opposite sides of the mouth. One side is randomly assigned to receive a stainless steel crown, and the other side receives a Bioflx crown. The placement of the two crowns is performed in two separate appointments, with an interval of 1 to 2 weeks between them. This approach allows the child to adapt to the new occlusion (bite) after the first crown is placed, ensuring a more stable result before the second procedure.

Study Record Dates

• First Submitted: January 17, 2026
• First Posted: January 22, 2026
• Study Start: August 1, 2025
• Primary Completion (Estimated): July 1, 2026
• Study Completion (Estimated): October 1, 2027
• Last Updated: January 22, 2026

Record last verified: 2026-01

Locations

VN (2)