Clinical performance and parental satisfaction of Bioflx, zirconia and stainless steel crowns in primary molars: a randomized controlled trial

Restoring primary teeth in young children poses challenges like behaviour management, parental satisfaction, and tooth preservation. While stainless steel crowns are traditional, zirconia and Bioflx crowns offer aesthetic alternatives. This study compared clinical outcomes and satisfaction among clinicians, children, and parents. This study was conducted on primary molars from children aged 3 to 8 years. A Randomized controlled trial included a total of 72 samples, divided into three different groups: Group 1 – Preformed Stainless-Steel Crowns ( n = 24, 3M™ ESPE™), Group 2 – Preformed Bioflx Crowns ( n = 24, Kids-e-dental LLP), and Group 3 – Preformed Zirconia Crowns ( n = 24, Kids-e-dental LLP). The crowns were evaluated based on various clinical and clinician parameters, and parental satisfaction at post-op, 3, 6, 9, and 12 months. At 12 months, crown retention was 91.6% for stainless-steel crowns, 87.5% for zirconia crowns, and 75% for Bioflx crowns. Zirconia crowns retained favourable gingival-health, stain-resistance, and clinician-rated esthetic scores in 100% of evaluated cases, although opposing-tooth wear was observed in 21%. Bioflx crowns retained 100% clinician-rated surface smoothness and esthetics, but their favourable plaque score declined to 63%. All parents in the Bioflx and zirconia groups were satisfied or very satisfied with crown size at 12 months, whereas 79% of parents in the stainless-steel group reported being “very little satisfied” with crown colour. Zirconia crowns maintained favourable aesthetic and gingival outcomes but were associated with greater opposing-tooth wear and required more extensive tooth preparation. Stainless-steel crowns had the highest retention but lower aesthetic satisfaction. Bioflx crowns retained favourable aesthetic ratings; however, the retention decreased. Overall, material selection should balance aesthetics, conservation of tooth structure, opposing-tooth wear, and retention requirements based on clinical priorities. CTRI/2023/05/052256 [Registered on date: 03/05/2023].