Which is the best implant

Dental implants - ceramic or titanium?

Implantology has developed rapidly over the past 40 years. The first documented attempts to implant a foreign body in the edentulous jaw took place in the 5th millennium BC. Instead of. The drawings submitted show shell remains that were inserted in place of the extracted tooth. Jordan and Magialo described in their book as early as the beginning of the 19th century Manual d’art dentaire (Handbuch der Zahntechnik) how to anchor a golden tube with claws after a tooth extraction. (Textbook “Dental Surgery” 3rd edition, Schwenzer, Ehrenfeld).

In the 20th century, experimentation continued with various metal alloys. These were mainly stainless steel, chromium, cobalt and molybdenum. Some could be placed in the bone (endosseous), the others could be placed under the periosteum on the bone surface (subperiosteal). The latter method could not establish itself in view of the biophysical demands on the implants.

The first dentist to propose titanium as a material in implantology was Formigini. In the 1970s, Leonhard Linkow and Per-Ingvar Brånemark were the pioneers of modern implantology and were the first to speak of "osseointegrated" implants. The latter contributed significantly to the development of modern implantology and carried out numerous experiments with titanium implants.

The ceramic implants fell by the wayside for a long time. On the one hand it was due to the fact that the focus was on titanium, on the other hand it was also due to the physical properties of the ceramic, which is very brittle and has a lower elasticity compared to titanium.

The status today

Before going into the individual physical and scientific findings that dentists and implantologists make use of today, some important parameters of implantology are explained at this point.

1. The beginning

Every and absolutely every implant must have a certain primary stability (i.e. the stability of the implant directly after it has been inserted into the jaw). A primary stability of a torque of 35Ncm is considered very safe. If primary stability is not ensured, the implant will not heal.

2. Bone quality

There are four different bone qualities in implantology - D1 to D4. D1 is the hard, compact bone, D4 ​​is the very soft, porous bone, like balsa wood. The bone quality is crucial for primary stability.

3. The dentures on the implants

Many of us envision that an implant replaces a tooth. In reality, implants are very often used today as anchors for securing prostheses, e.g. B. for full dentures. Two to four implants can give a full denture a much better hold. In this way, implants are exposed to a very high level of stress. There is very little evidence of ceramic implants on this subject, including no long-term studies.

The titanium implant

The material for the titanium implants is "pure titanium". This means that this metal has a purity of over 99.9%. The surface of all implants is coated with oxygen. That's why an implant can heal. The body recognizes the oxygen layer on the surface and the bone-forming cells (osteoblasts) form fresh bones. This process has already been investigated hundreds of times with titanium implants and shows that a waiting time of 3 to 6 months is necessary, depending on the bone quality, primary stability and bone augmentation measures, until adequate osseointegration (integration into the bone) has taken place. This process works perfectly with implants made of titanium.

Why do you lose titanium implants anyway?

As just mentioned, the “pure titanium” still contains around 0.01% foreign materials, including nickel (Thomas et al). Even if it is present in such a low concentration, it could lead to an inflammatory reaction, extremely rarely to a real allergic reaction with classic symptoms. The other cause, based on the metallic properties of the implants, is phagocytization (the absorption of the particles into the cells) of titanium particles. It is a more pronounced inflammatory response triggered by macrophages and monocytes. After titanium particles have been phagocytosed by the cells mentioned above, they can release messenger substances such as TNF-α and IL-1β. These messenger substances then mediate increased osteoclast activity. (Bone-degrading cells).

Note: The release of the messenger substances takes place after each implantation. The amount of messenger substances released varies, but the risk of inflammation increases with an increased amount.

The osteoclasts are able to break down 100 times more bone for the same amount of time as the osteoblasts (bone-building cells) can build. This leads to a loss of stability of the implant in the implant bed and thus to a loss.

Note: This complication is favored by other factors such as bone quality, general condition of the patient (a patient with many allergies may also be more likely to be “allergic” to titanium than a perfectly healthy patient), smoking and diabetes.

The benefits of titanium implants

As a material, titanium is very flexible and resilient. Due to these properties, a good primary stability can be achieved with relatively short implants and they can be adequately loaded. The thread of the implant is one of the decisive factors for the primary stability. Many implant systems, e.g. B. Ancylos, one of the best known nationwide, do not have an active, cutting thread. In this case, the thread must be "cut" beforehand before the implant can then be inserted. This is a little gentler on the bone, but may not allow you to have such good primary stability in the soft bone. At this point it must be mentioned that there are techniques that can be used to achieve good primary stability even in softer bones. There are now implant systems such as Megagen, Nobel Active or ICX Active, which have a very aggressive thread and thus achieve very good primary stability even in the softer bone. This enables immediate implantation.

The ceramic implant

As early as the 1960s and 1970s, attempts were made to manufacture implants from ceramic. The first material used was aluminum oxide (Al2O3). Sami Sandhaus and Willi Schulte designed the so-called CBS implant back in the 1960s. CBS stands for crystalline bone screw and is still used today, albeit slightly modified. In the 90s, zirconium oxide (ZrO2) also came as the successor to aluminum oxide. The special thing about it are its physical properties. These include the high flexural strength (1,200 MPa), high hardness (1,200 Vickers), high compressive strength (2,000 MPa) and the modulus of elasticity (210 GPa) (zwp online from 07/29/15). These properties allow better loading of the implant.

One advantage of the zirconium implants is the lower adhesion of the coverings. In comparison to titanium, a significantly lower bacterial contamination of the surface was found (Scarano et al. Rimondini et al.).

Nevertheless, due to its nature, the material remains inferior to the titanium implant. In the early 1990s it was found that these had a significantly higher failure rate in the healing phase than titanium implants.

Note: Zirconium oxide is relatively brittle and therefore more prone to fracture than titanium.

An important factor for osseointegration is the area of ​​the implant that is covered by the bone - BIC (bone implant contact). Three important studies on the subject have been published (Kohal et al. Sollazzo et al. Stadlinger et al.). In conclusion, it can be said that the titanium implant is slightly superior to the ceramic implant.

Dental implant material - price, aesthetics and conclusion

The price?

As always, this is a crucial factor for everyone. The ceramic implants cost up to many times more than titanium implants. You can find a price overview here: https://www.zwp-online.info/files/49969/iehb16_268-273_mu_keramik.pdf

Note: The costs that an implant produces, including all screws, impression posts, laboratory analogs, etc., are passed on to you on a one-to-one basis.

Aesthetics?

The optical component of a white implant is undoubtedly better than that of a gray titanium implant. This is particularly important in the anterior region if part of the implant should be exposed after years. Even if the implant has healed well, it can happen that part of the implant is exposed as a result of general illnesses, incorrect cleaning technique, etc. In such cases the white zirconium implant is superior to the titanium implant.

Conclusion on the respective implant material

The renaissance that zirconium implants are experiencing is leading to new research results and an overall better prognosis. However, it must be noted that an essential part of the research on surface properties is carried out, for which there are currently no long-term studies, i.e. over a period of 15 years. These aspects of research and predictability are already established for titanium implants and are very reliable.

It must also be noted that in view of the still very manageable range of offers for ceramic implants, the price will remain relatively high compared to the tried and tested titanium implants.

Nonetheless, the trend is towards ceramic implants, also because of the better aesthetics. For the moment, however, this remains more of an alternative and not a substitute for titanium implants, especially with immediately loadable implants.