When a conversion prosthesis is not available, it is sometimes necessary to fabricate a short-term denture format implant-supported acrylic T.I.P. This will only serve as an interim device until the final prosthesis can be made.
The cast able telescopic screw attachment (Preat Corporation) is a treatment plan alternative when only one implant is available for support. This eliminates the need for an occlusal opening that would accompany a standard key latch or tube and screw attachment. Since this is a castable pattern, any suitable metal may be used. This system may be used in conjunction with abutment telescopic copings. A minimum of 4.5 mm of vertical space from tissue to opposing tooth contact is required.
In working with implant-supported prostheses since 1982, many difficult and unusual problems have been encountered. The techniques that we have developed through our long-term experience can save time, experimentation, and frustration.
This maxillary cast shows six Core-Vent implant replicas. The long axis angulation of these implants presents a difficult situation in which to create the desired esthetic result.
The angulated abutment by Nobelpharma is a very innovative component designed to adjust access hole position, prosthetic screw angulation and improve cosmetics. This thirty-degree, twelve-sided, internal-designed component offers twelve different positions to drastically change the angulation of a severely misaligned implant.
The Double Casting Technique
The following patient treatment demonstrates one laboratory process used to overcome problems encountered when implants are aligned in unusual positions. These problems often become more apparent at the laboratory stage rather than in the clinical setting.
A carbon fiber frame (currently in development by Nobelpharma AB), may offer the patient a new concept in osseointegrated restorations. This new material is designed to substitute for the metal portion of the implant-supported substructure. The metal casting is eliminated, in addition to all metal finishing and polishing procedures. This material is much lighter than metal and is very easy to work with, especially after it is cured. The carbon fiber frame might be a good alternative where allergic reactions are a concern. It should be noted that this technique is still experimental and testing is in progress. Longterm clinical results are as yet unproven.
The Slant-Lock System is marketed as the first system which gives the stability of a screw-retained fixed bridge and the benefits of a removable prosthesis. Since the overdenture is removable by the patient, the substructure bar and cylinders, as well as the surrounding tissue area, are easily accessible for hygiene maintenance. This is a good treatment plan for patients with limited manual dexterity. As in other overdenture applications, the fully extended denture base can replace lost bone and tissue. An important consideration is the vertical dimension. The latch and housing must be placed below the cervical of the prosthetic teeth to achieve the proper esthetic results. Space requirements can be determined after the initial wax setup and fabrication of the matrix are complete.
The Cera One Abutment and gold abutment screw is designed to accept a cement able ceramic core restoration. The ceramic cap is made from densely sintered aluminum oxide (99.7% Al2 03). With no metal core, the esthetic capabilities are increased. The short cap measures 5.8 mm in height with a .7 mm thickness. The tapered long ceramic cap is useful in anterior applications.
A master cast with a Bdlnemark System angulated abutment in the area of the maxillary right canine. After articulation, it was evident that the fixture placement and angulation would prevent standard procedures from achieving an acceptable esthetic result.