The final stage of implant rehabilitation is transferring the intra-oral data to the dental laboratory for the fabrication of the definitive restoration or prosthesis. The definitive restoration can be fixed, supported either solely by implants, or in combination with natural teeth abutments. A removable prosthesis is supported by implants, with or without soft tissue support. The decision of the definitive restoration is made at the treatment planning stage, and determines the type, number and positioning of the fixtures and abutments for supporting the final restoration(s).
Following successful osseointegration, the intra-oral data needs to be transferred to the dental laboratory for prosthetic rehabilitation of the implant fixtures. The intra-oral data includes the number, location, size and angulation of implants together with surrounding soft tissues and the adjacent and opposing dentition. This is accomplished by taking an impression, face-bow and occlusal records. At present, the analogue method is the most popular, using PVS or polyether impression materials in a custom-made tray, but in future will be replaced by digital intra-oral impressions.
The analogue method involves using impressions copings (made of plastic, titanium or anodised aluminium), which can be for closed or open impression trays (the latter if the angle of the fixture(s) is anticipated to hinder withdrawal of the tray). In the dental laboratory, a stone model is poured using the corresponding implant analogues (made of stainless steel or brass), in preparation for abutment fabrication. The contemporary method for designing both implant abutment(s) and the definitive restoration(s) is by CAD/CAM technology. Alternately, abutment(s) and restoration(s) can be waxed and cast using conventional prosthetic protocols.
Cement-retained restorations can be used for either single crowns or multiple-unit FPDs. First, the abutment is screwed or tappe/>