New embedding medium for sectioning undecalcified bone.

Methylmethacrylate (MMA) is the most commonly used embedding medium for sectioning undecalcified bone; however, a number of problems exist with its use in a research laboratory. MMA requires a long infiltration time and temperature control, and it reacts with many polymers. We used Kleer Set resin as an alternative embedding medium for sectioning undecalcified bone specimens. Fluorochrome labeled bone specimens were sectioned transversely using a ground section technique and longitudinally on a sledge macrotome. The slides were viewed using both transmitted light and epifluorescence microscopy. High quality sections were obtained using Kleer Set resin for both sectioning techniques. We have shown that this new embedding medium is simpler, safer, quicker to use and does not interfere with visualization of fluorochromes.