Comparative Clinical Evaluation of BioFlx, Zirconia, and Stainless-Steel Crowns in Primary Molars

A well-fitted preformed stainless-steel crown will be chosen by measuring the mesiodistal dimension of the tooth or its contralateral counterpart, using a graduated periodontal probe for guidance. (6) Tooth preparation will be carried out with #835 diamond fissure bur to reduce occlusal surface up to 1 to 1.5 mm. The interproximal reduction will be made mesially and distally using #169 L tapered diamond bur around 0.5 mm to clear the contact area creating a feather edge finish line. The selected crown size will be checked, and a trial fit will be done before cementation. The crown will be cemented using self-cured RMGI luting cement. The excess will be removed, and proper occlusion will be checked.

The material for crown restoration for this group is the preformed zirconia crown. Tooth preparation will be started by occlusal reduction (1 to 1.5 mm) using #835 diamond fissure bur. The interproximal reduction will be done mesially and distally with #169 L tapered diamond bur in such a way that a straight probe passes freely through the contact area. Rounding of line angles will be done and a knife-edge finish margin of the proximal surface will be obtained avoiding any ledge formation. The selected crown will be placed and checked for a passive fit. Consistent firm finger pressure will be applied during cementation with self-cured RMGI luting cement. Finally, crown placement will be checked.

The prefabricated BioFlx crown will be used in this group. A similar-sized preformed crown will be selected. Tooth preparation will be carried out similarly to traditional SSCs with #835 diamond fissure bur for occlusal reduction by 1-1.5 mm including the central groove. The proximal preparation will be done mesially and distally with #169 L tapered diamond bur around 0.5 mm to clear the contact area creating a feather edge finish line. Placement of the crown will be achieved by a snug fit. Crown cementation will be carried out using self-cured RMGI luting cement and the excess cement will be removed using a floss or an explorer. (13) Finally, crown placement will be checked