What should you consider when producing CAD/CAM hybrid abutments?
When is standard sufficient and when should something be tailor-made? With an implant abutment, this is quickly answered: Individual production (CAD/CAM abutments) is state of the art. This article is a brief overview of the many important factors that need to be taken into account with CAD/CAM abutments.
Design of the implant exit
When designing the implant exit from the soft tissue, it is worth comparing it with the natural tooth. The nomenclature “gingiva” applies to the soft tissue associated with the tooth. When it comes to implants, this is referred to as peri-implant “mucosa”. Although the gingiva and the mucosa have similarities, they have at least as many differences. They differ e.g. B. in the composition of the connective tissue, the arrangement of the collagen fibers and the distribution of the vascular structures beneath the junctional epithelium. With the implant, forces are transferred directly into the bone, without any cushioning by the periodontal ligament.
Requirements for CAD/CAM abutments
An efficient and material-safe way to produce individual implant abutments is CAD/CAM-supported production in the dental laboratory or at manufacturing service providers. Attention: CAD/CAM abutments should meet the standards of prefabricated - industrially manufactured - abutments in terms of quality and quality.
CAD/CAM hybrid abutments
CAD/CAM hybrid abutments combine the positive material properties of titanium with the optical and biocompatible advantages of ceramic. The superstructures consist of a ready-made adhesive base (titanium). An individually manufactured, CAD/CAM-supported zirconium oxide hybrid component is glued onto this.
Manufacturing the zirconium oxide hybrid portion
Cross section CAD/CAM hybrid abutment.
The CAD design is carried out according to the emergence profile. The assembled titanium adhesive base is supplemented analogously to the connection geometry from the virtual library. After production, the zirconium oxide hybrid component is bonded to the titanium base in a force-fitting manner. The precise fit of the zirconium oxide hybrid component is an important aspect. It should be noted that the fit is influenced by many parameters (calibration of the milling machine, consistent cutting properties of the milling cutters, sintering process, etc.). Here, central production from a specialized provider with certified quality processes may be superior.
Bonding the zirconium oxide hybrid portion to the titanium base
The bonding of the titanium base and the zirconium oxide hybrid component is equally important. What is needed is a standardized procedure whose protocol must be consistently followed. The adhesive base consists of the adhesive surface, adhesive shoulder and implant connection geometry. The adhesive surface and the top of the adhesive shoulder are blasted with aluminum oxide powder (1 - 1,5 bar, 50 - 110 µm). Attention: The underside of the adhesive shoulder remains untouched from the transition to the implant. Bonding is carried out using a special bonding composite, whereby the procedure is strictly based on the manufacturer's specifications.
The exact steps of conditioning and the actual bonding as well as important processing instructions are shown in the video:
Attention: medical product!
Abutments are medical devices that are classified as semi-critical (RKI). Accordingly, professional cleaning is recommended before inserting it into the mouth. Evaporation is not sufficient and fails to achieve the disinfection effect required by standards. Even if there are still no adequate answers to many questions, the problem cannot be negated. Implant prosthetic abutments should not be placed in the mouth without being cleaned. In a summary of an expert discussion on the topic, EADT eV presents the current study situation on the various options in detail. Download the expert paper: Here
Carsten Fischer, Frankfurt/Main