Polymethylmethacrylate (PMMA): bone cement Propertieis
- no adhesive properties. Works as grout, not glue.
- does not chemically bond to bone or implants
- three times stronger in compression than tension.
- peak blood levels of monomer occur 3 minutes after the cement is placed.
- monomer is cleared by the lungs.
- hypotension associated with cement is more closely related to diminished blood volume than to circulating monomer levels.
- Higher porosity = decreased tensile and fatigue strength. Manually mixed = 27%. Vacuum mixed = 1%
- Antibiotics in cement does not appreciably affect compressive or tensile forces. Fatigue strength may be reduced.