CASE 3
A 62-year-old woman was administered full-arch implant treatment on the
upper jaw. All one-step-type implants (IT-implant; Platon Japan) were
inserted in the parallel direction using Guided Surgery (Straumann AG).
The metal frame was made from a rigid, nonprecious, cobalt–chromium
alloy (Cobatole; IDS, Tokyo, Japan) and intraorally luted abutments to
frame with resin cement (RelyX Ultimate). The use of intraorally luted
abutments to the frame can compensate for the fit discrepancies of the
implant-supported prostheses, allowing the fabrication of retrievable
implant-supported prosthesis with minimal strain. Zirconia crown
prepared using a milling machine (DWX-52DC; Roland, Shizuoka, Japan) was
luted to the metal frame. The superstructure was frictionally connected
to the abutment with a reverse-taper lock system without the use of
cement or screws (Figure 9). Using an IT crown remover (Platon Japan),
the frictional force is released, facilitating an easy superstructure
removal (Figure 10,11). No mechanical or biological complications,
including inflammation of the peri-implant soft tissue or resorption of
the peri-implant bone, were observed during the 4-year follow-up period
after the fitting (Figure 12).