New in our clinic is the use of DELTA ceramic-on-ceramic prostheses (figure 4 and 5). The Ceramtec Biolox®delta is a prosthesis which has a new ceramic mixture. Due to the adding of zirconium and chromiumoxide (pink colour), the couple is now even better than the previous ones (Biolox®Forte).
In all the next items it shows that, the new material tested better than the other ceramics.
- Strength (figure 1)
- Fracture toughness (figure 2)
- Stability (chemical and hydrothermal)
- Hardness (figure 3)
Beside these test-outcomes, the material used results in less brittle ceramic, which reduces the possibility of scratches on the surface. These effects make the couples less vulnerable for wear.
Since the ceramic bearings are stronger, it is possible to use smaller acetabular shells. This means the surgeon has the opportunity to choose bigger femoral heads which will fit into smaller acetabular shells. This means higher stability, bigger ´Range of Motion` and less risk of impingement and wear of the material.
All these improvements have made these couples last in vitro longer than the others. The Biolox®delta products have obtained the CE Mark, which is the European mark of regulatory approval. In the USA some applications are already cleared and others undergoing clinical investigations.