When cutting sections from paraffin blocks, the most common cause of unsatisfactory sections is which?

• A. A dull blade
• B. A poor blade edge
• C. An air bubble in the mounting medium
• D. Inadequate fixation

Answer: (B)

A clean, sharp blade edge is essential for cleanly slicing paraffin-embedded tissue. When the blade edge is poor—dull, nicked, or uneven—the tissue can’t be sheared smoothly, so it tears, pulls, or chips and the ribbons become wavy or irregular in thickness. This cutting defect is the most common reason sections come out unsatisfactory because it directly affects the moment the blade contacts the tissue and governs the ability to produce uniform, intact sections. Regularly inspecting and refreshing blades, and keeping the edge true and free of nicks, directly improves section quality. Mounting-related issues like air bubbles or poor fixation affect other aspects of the prep but are not the primary cause of cutting artifacts as frequently as a compromised blade edge.