In Prosthodontics and Restorative Dentistry the bond strength of cements to dental materials and tooth structure is well researched, but limited information is available on bond strength to ceramic substructure materials.
Objective: To determine the bond strength of three cementation materials, (Polycarboxylate, Resin-modified Glass–ionomer,
Self Adhesive Resin) when used on two popular ceramic substructure materials (Procera-Alumina and Procera-Zirconia).
Methods: 8mm diameter cylinders of the two ceramic substructures were embedded into metallic cylinders and 4mm cylinders of the same substructure material were then cemented onto the embedded 8mm cylinders using three different cements, namely Poly-F, Fuji Plus,
and Rely-X. Bond strength was tested using a Bencor Multi-T unit in a Zwick Z010 Material Testing Machine
. Results: Variation in bond strength was high.
Bond strength (MPa) of the three cements when bonding Procera-Alumina & Procera-Zirconia SHAPE Substructure | Poly-F | Fuji Plus | Rely-X | Material | Force MPa) | SD (CV%) | Force (MPa) | SD (CV%) | Force (MPa) | SD (CV%) | Procera Alumina | 176.57 (n=20) | 45.70 (25.88) | 58.33 (n=8) | 33.66 (57.70) | 205.17 (n=10) | 59.46 (28.98) | Procera Zirconia | 196.02 (n=17) | 54.72 (27.91) | 137.78 (n=14) | 35.21 (25.56) | 300.35 (n=16) | 67.97 (22.63) | |
Bond strength was statistically compared by the Student-t test using Statistix 8 Software. Results of bond strength to both Alumina and Zirconia revealed the same pattern, with Rely-X yielding the strongest bond strength, Fuji Plus yielding the weakest bond strength and Poly-F in between. Bond strength of Fuji Plus and Rely-X to the two substructure materials showed a statistically significant difference (p<0.05), whilst bond strength of Poly-F to the two substructure materials was not significantly different (p>0.05). Comparing bond strength to Alumina and Zirconia as substructures respectively, showed significant differences. Conclusion: Rely-X is the cement of choice to be used in cementing Alumina and Zirconia substructure materials. Project sponsored by Nobel Biocare Services (AG Postfach CH-8058 Zurich-Airport Switzerland).