The temperature of the oven used to maintain a supply of melted paraffin for embedding tissue is most commonly at

• A. 50 C
• B. 60 C
• C. 70 C
• D. 40 C

Answer: (B)

Molten paraffin must stay fluid enough to infiltrate tissue but not be so hot that it damages or distorts the tissue. Paraffin used for embedding is heated to a temperature where it remains readily pourable—typically around 60°C. At this temperature the paraffin is viscous enough to hold tissue in place and allow proper infiltration and orientation, while being low enough to minimize heat-related tissue distortion. If the temperature were too low (for example around 40–50°C), the paraffin would be too viscous or begin to solidify, making embedding difficult. If it were much higher (around 70°C), excessive heat could degrade tissue morphology and affect downstream staining. Therefore, around 60°C is the standard, optimal compromise for embedding work.