Effect of abutment types and resin cements on the esthetics of implant-supported restorations.

PURPOSE

The aim of the study was to evaluate the optical properties of new generation (3Y-TZP) monolithic zirconia (MZ) with different abutment types and resin cement shades.

MATERIALS AND METHODS

A1/LT MZ specimens were prepared (10 × 12 × 1 mm, N = 30) and divided into 3 groups according to cement shades as transparent (Tr), yellow (Y) and opaque (O). Abutment specimens were obtained from 4 different materials including zirconia (Group Z), hybrid (Group H), titanium (Group T) and anodized yellow titanium (Group AT). MZ and abutment specimens were then cemented. L, a, and b parameters were obtained from MZ, MZ + abutment, and MZ + abutment + cement. ΔE (between MZ and MZ + abutment), ΔE (between MZ and MZ + abutment + cement) and ΔE (between MZ + abutment and MZ + abutment + cement) values were calculated. Statistical analyses included 2-way ANOVA, Bonferroni, and Paired Sample -Tests ( < .05).

RESULTS

Abutment types and resin cements had significant effect on L, a, b, ΔE, ΔE, and ΔE values ( < .001). Without cementation, whereas zirconia abutment resulted in the least discoloration (ΔE = 0.68), titanium abutment caused the most discoloration (ΔE = 4.99). The least ΔE = 0.68 value was seen using zirconia abutment after cementation with yellow shaded cement. Opaque shaded cement caused the most color change (ΔE = 5.24). Cement application increased the L values in all groups.

CONCLUSION

The least color change with/without cement was observed in crown configurations created with zirconia abutments. Zirconia and hybrid abutments produced significantly lower ΔE and ΔE values in combination with yellow shaded cement. The usage of opaque shaded cement in titanium/anodized titanium groups may enable the clinically unacceptable ΔE value to reach the acceptable level.