## Introduction
The “Holy Grail” of joint replacement is permanent fixation. While cement provides a mechanical lock, **Biological Fixation**鈥攚here the patient’s own bone grows *into* the metal鈥攐ffers a lifetime bond. This is made possible through **Porous Coating Technology**.
## The Requirements for Ingrowth
For bone cells (osteoblasts) to migrate into an implant, three conditions must be met:
1. **Pore Size:** The holes must be between **100 and 400 microns**. Too small, and the cells can’t fit; too large, and the structure is too weak.
2. **Porosity:** The coating should be 50-70% open space to allow for vascularization.
3. **Stability:** The implant must have zero movement (less than 150 microns) during the first 6 weeks of healing.
## Ortholyx Coating Methods
* **Titanium Plasma Spray (TPS):** Molten titanium droplets are sprayed onto the implant, creating a rough, “mountainous” topography with high friction.
* **Sintered Beads:** Small metal spheres are heated until they bond together, creating a classic, reliable porous network.
* **3D Printed “Trabecular” Structures:** The latest innovation. We use 3D printing to create a structure that exactly mimics the architecture of human cancellous bone.
## Bio-active Enhancement: Hydroxyapatite (HA)
Ortholyx often adds a thin layer of **HA (a natural bone mineral)** over the porous titanium. This acts as a “chemical signal” that tricks the body into thinking the metal is a natural part of the skeleton, significantly accelerating the speed of initial ingrowth.
## Conclusion
Porous coating is the bridge between medtech and biology. By utilizing the most advanced 3D printing and plasma spray techniques, Ortholyx ensures that our cementless joints become a living part of the patient’s body.