Purpose: To evaluate the long-term outcome of all-ceramic resin-bonded fixed dental prostheses (RBFDPs) made with a two-retainer design or a cantilever single-retainer design.
Materials and Methods: Overall, 38 anterior RBFDPs were made from a glass-infiltrated alumina ceramic (In-Ceram). Sixteen RBFDPs had a two-retainer design, while 22 RBFDPs had a cantilever single-retainer design. Phosphate monomer containing luting agents were used either after silica coating and silanation or after air-abrasion only. The mean observation time in the two-retainer group was 120.2 months and in the single-retainer group 111.1 months.
Results: No restoration debonded. In the two-retainer group unilateral and bilateral fractures of the connectors occurred. In the case of unilateral fracture, the pontic remained in situ as a cantilever RBFDP for several years. In the single-retainer group, only one FDP fractured and was lost 48 months after insertion. The 10-year survival rate was 73.9% in the two-retainer group and 94.4% in the single-retainer group. When unilateral fracture of a FDP was taken as a criterion for failure, the 10-year survival rate decreased to 67.3% in the two-retainer group.
Conclusion: Cantilever all-ceramic RBFDPs are an adequate alternative to two-retainer RBFDPs.
Keywords: adhesive, all-ceramic restoration, alumina ceramic, cantilever fixed dental prosthesis, ceramic bonding, ceramic fracture, resin-bonded fixed dental prosthesis, survival rate