Shear strength of self-curing acrylic cement

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Materials Engineering

Background:

• Surgical bone cements are widely used in orthopedic procedures.
• Evaluating the mechanical properties of bone cements is crucial for patient safety and treatment efficacy.
• Simplex P is a commonly used bone cement, and understanding its limitations is important.

Purpose of the Study:

• To experimentally determine the shear strength of surgical Simplex P bone cement.
• To compare the shear strength of Simplex P to that of compact bone.
• To investigate the effects of barium sulfate addition and varying loading rates on shear strength.

Main Methods:

• Experimental evaluation of the average shearing strength of surgical Simplex P bone cement.
• Comparison of cement shear strength with reported values for compact bone.
• Analysis of the influence of 10% barium sulfate U.S.P. inclusion on shear strength.
• Assessment of varying loading rates (0.005-0.5 in/min) and short-term curing times (2-168 hours) on shear force at failure.

Main Results:

• The average shear strength of surgical Simplex P was found to be 5,762 ± 180 psi.
• Compact bone exhibits an average shear strength of approximately 10,000 psi.
• Inclusion of 10% barium sulfate did not adversely affect shear strength.
• Loading rate and curing time showed minor effects on shear force at failure, with cement strengthening over time.

Conclusions:

• Surgical Simplex P bone cement exhibits lower shear strength compared to compact bone.
• The cement should not be used as a substitute for bone whenever possible due to its shear resistance limitations.
• Radiographic additives and curing duration do not compromise the cement's shear strength significantly.