Titanium implants are the most common epithesis carriers today. They grow into a bone and end in small metal pins over the skin to which the epithesis can be attached.
What is an epithesis carrier?
Implant-fixed epitheses are the most common types of anchorage today. These are definitive epitheses that are in a definitive position. Illustration shows an ocular epithesis. Epithesis carriers serve as a retaining device for an implant-fixed epithesis. The implant-fixed epithesis is the third anchorage form of craniofacial epitheses, in addition to the spectacle-retained and adhesive-fixed forms. As materials foreign to the body, craniofacial epitheses, unlike prostheses for example, serve primarily to compensate for aesthetic facial defects and thus to restore a relatively inconspicuous face, for example after an accident. Implant-fixed epitheses are the most common types of anchorage today. These are final epitheses that are in definitive position. More often than expensive ceramic implants, titanium implants are now used as epithesis carriers. The epithesis can be attached to tiny titanium pegs that protrude from the skin, via a variety of systems.
Shapes, types and styles
Epithesis carriers can provide defined support for the epithesis, for example, through magnetic connections. Such an option is available for orbital, nasal or ear muscle epitheses, among others. In this case, the titanium implants are connected with corrosion-resistant mini magnets. Depending on the body site, these magnets can be equipped with protection against transverse forces, which prevents the epithesis from slipping. Such mini-magnets are also called long-lip magnets. Mini-magnets with protection against lateral displacement, on the other hand, are called lip magnets. Less often used today is a bar-rider design for anchoring the epithetic attachments in the titanium bone implant. In this case, the bar rider engages on a bar joint and thus supports the epithesis. This variant offers significantly less protection against slippage and is associated with a higher foreign body sensation. The same applies to fastening with press studs or staples, which are rarely performed today.
Structure and mode of operation
In surgical epithetics, the use of an osseointegrated (bone-integrated) titanium implant as an epithesis carrier is carefully planned in advance. The designs must be well thought out in order to be able to support the epithesis in the long term. Hygienic requirements are also taken into account during planning. For example, the connection point between the epithesis and the titanium implant must be cleanable with as little effort as possible. Planning requires both materials science and knowledge of epithetic design principles. The titanium implant is inserted into a nearby bone in one operation. Tiny metal pins usually extend from the implant through the skin to serve as fixation points when the epithesis is attached. Whether the epithesis is attached to the metal pins via clips, magnets, snaps or a bar-and-rider design is determined by the patient’s personal preference. Active people usually care about the firm and relatively definitive hold of the epithesis. They want to prevent the epithesis from shifting, for example, during sports. This often distinguishes their requirements from older people, whose lives are quieter. The quieter the life, the less important it is to have a defined and bombproof fit of the epithesis. Often, older people in particular are more concerned about the ease of handling the epithesis or the ease of cleaning the passage point instead of the high level of security against displacement. A good epithetist will take these individual requirements into account already during the preliminary considerations for the epithesis. As a rule, some time elapses after insertion of the titanium carrier until the epithesis carrier is firmly incorporated in the bone. Only when this is the case is the epithesis placed.
Medical and health benefits
Epitheses have no physiological functional benefit, but they do have psychological functional value. As noted above, epithetic restorations are usually prescribed for purely aesthetic purposes. Most commonly, patients are war casualties, cancer survivors with disfigurement, or patients with deformity. Especially in the face, disfigurements are a high burden on the patient’s psyche.The face acts like an interpersonal calling card. It plays a major role in interpersonal interaction and thus also influences a person’s integration into social groups. Therefore, patients with facial defects often live an isolated and lonely life with little social interaction. On the one hand, they are often ashamed of their disfigurement. On the other hand, they are sometimes exposed to active ridicule or at least receive horrified or curious looks from other people. They can avoid this by isolation, but the loneliness is not without consequences for the psyche. Sometimes depression occurs as a result of facial disfigurement or deformity. Self-esteem is diminished or almost non-existent. In social interactions and in everyday social life, those affected find it difficult and feel insecure, so that everyday life and work, for example, become a challenge that can hardly be mastered. An epithesis can give them back their security in social life. It thus helps with reintegration and reduces psychological stress. Epitheses without bone-integrated epithesis carriers fulfill this purpose only to a limited extent, as they are less well defined and therefore leave a great deal of uncertainty. Defined epitheses using titanium implants as epithesis carriers minimize the risk of slippage and thus reduce residual uncertainty.
