Method for embedding temporal bones of rats in methyl-methacrylate

The commonly used method of preparing the temporal bone for light microscopy is a refinement of a basic formula that has been employed for a century. This process includes fixation, decalcification, neutralization, dehydration, embedding in celloidin, and hardening. The main disadvantage of this process is that decalcification is performed. This article describes a new method for preparing the temporal bone of rats for light microscopy. The main advantage of this new method is that no decalcification is involved, so that all bony elements are retained in their normal shape and location, and even retain some enzymatic activity. Other advantages are that the fixation is reversible and the process is short (approximately 2 weeks) and therefore relatively inexpensive. Our vast and positive experience with this technique has led us to report this method not in a specific experiment, but rather as a specific laboratory technique.