Misfit and microleakage of implant-supported crown copings obtained by laser sintering and casting techniques, luted with glass-ionomer, resin cements and acrylic/urethane-based agents.

Objectives: This study evaluated the marginal misfit and microleakage of cement-retained implant-supported crown copings.

Methods: Single crown structures were constructed with: (1) laser-sintered Co-Cr (LS); (2) vacuum-cast Co-Cr (CC) and (3) vacuum-cast Ni-Cr-Ti (CN). Samples of each alloy group were randomly luted in standard fashion onto machined titanium abutments using: (1) GC Fuji PLUS (FP); (2) Clearfil Esthetic Cement (CEC); (3) RelyX Unicem 2 Automix (RXU) and (4) DentoTemp (DT) (n=15 each).

In vitro vertical misfit evaluation of cast frameworks for cement-retained implant-supported partial prostheses.

Objectives: To evaluate the influence of the alloy type and the associated investing and casting techniques, on the marginal adaptation of bridge structures luted onto prefabricated implant abutments.

Methods: Thirty frameworks for three-unit posterior-lower bridges were waxed and cast (10 of cobalt-chromium, 10 of titanium and 10 of palladium-gold). Each structure was cemented onto two prefabricated implant abutments with a special clamp designed to maintain constant seating pressure.