Aim: This study aimed to assess the marginal adaptation and internal fitness of Stainless-Steel crowns (SSCs) versus Zirconia crowns for extracted first primary molars cemented with different luting cements. Materials and methods: Forty primary first molars were divided into two equal groups (n = 20). In the first group, the teeth were prepared to receive SSCs, and the other group received zirconia crowns. Each group was further sub-grouped into four groups (n = 5) according to the luting cement. Results: Stainless-Steel crowns had significantly lower marginal gap width than zirconia crowns using glass ionomer cement (GIC), resin-modified glass ionomer cement (RMGIC), and self-adhesive resin cement, and non-significantly lower using bioactive cement. Self-adhesive resin cement and bioactive cement had significantly statistically higher values of marginal adaptation than GIC (p<0.001). In the zirconia group, SSCs had significantly lower internal gap width than zirconia crowns using GIC, SARC, and BC and non-significantly lower using RMGIC. Bioactive cement showed a significantly higher mean value than other cements (p<0.001) in the zirconia group.

Internal fitness; Marginal adaptation; Stainless-steel crowns; Zirconia crowns; Cement