Material choice in biomedical devices is not an easy task...
The different properties of a material for biomedical purpuoses and the interaction with the body of the patient are utterly important. Thermal properties of the orthopedic implants are of high importance as well, especially when it is in contact with brain, eye, and other thermally sensitive organ.
Partnering with AIP Tech we have studied the complication the patients may have when undergoing cranioplasty with polyetheretherketone (PEEK) and titanium implants. Here are several points we discovered for ourselves and eager to share with you.
- The cranial implants are basically made of polyetheretherketone (PEEK) and titanium alloy (Ti6Al4V)
- Ti6Al4V is stronger than PEEK
- The thermal conductivity of Ti6Al4V (7.5 W/mK) is much higher than that is of PEEK (0.25 W/mK)
- Ti6Al4V (3.7164 g/cm3) is heavier than PEEK (1.308 g/cm3)
- The usual thickness of cranial implant made of Ti6Al4V is 2.5mm while PEEK is 3mm. The thickness of natural bone is 6-11mm
Our calculations show that when having a shower at 42 ºC water for 10 minutes, the temperature gets 37 ºC in the boarder of dura-brain in the natural bone case. When changing the natural bone to the titanium implant, the temperature gets to 39.2 ºC. When PEEK is used as an implant, the temperature gets to 37.3 ºC.