Microleakage of Preveneered Stainless Steel Crowns Repair Material

Objectives: To evaluate microleakage at the preveneered Stainless Steel Crowns (SSCs) and repair material interface after using two different methods of surface treatment.

Methods: Twenty-four preveneered incisor SSCs (NuSmile® Primary Crowns, Houston, Texas) used in this study. Crowns were embedded in self-cure acrylic resin with their labial surface parallel flat to the floor. A quadrangular cavity with an internal space of 4 x 4 x 2 mm was made in the labial surface of each crown. Specimens were randomly divided according to the surface treatment into three groups of eight each. Group 1 served as control with no surface treatment while groups 2 and 3 were treated with self-etch (Adper™ Prompt™ L-Pop™) and total etch (35% phosphoric acid gel + Adper™ Scotchbond™ Multi-Purpose Plus) adhesives respectively. All cavities were restored with Filtek™ Supreme Plus. The repaired specimens were stored in distilled water for 24 hours. The specimens were prepared for microleakage and immersed for four hours in a 2% methylene blue buffered dye solution. The specimens were transversely sectioned with a double-faced diamond disk. The extent of microleakage was evaluate and scored. Data were analyzed using the Kruskal-Wallis test at a significance level of 5% to determine significant differences among the three groups. Pairwise comparisons were then made using the Mann-Whitney test.

Results: Group 1 showed the highest mean microleakage. Kruskal-Wallis test revealed statistically significant differences between the three groups (p≤0.00001). There was a statistically significant difference between group 1 and group 2. There was also significant difference between group 1 and group 3. However, there was no significant difference between group 2 and group 3.

Conclusions: The method of repair using self-etch or total etch adhesive and flowable composite prevented microleakage at the preveneered stainless steel crowns and repair material interface.