How much wax should surround the tissue during embedding?

During the embedding process, the surrounding wax serves several critical purposes, including providing support for the tissue specimen during sectioning and preventing damage to the delicate structures within the tissue. A thickness of approximately 2 mm of wax around the tissue is optimal because it offers adequate structural integrity while not being excessively thick, which can complicate sectioning. Additionally, this thickness ensures that the heat from the microtome does not excessively affect the tissue, as excessive thickness may create a barrier to optimal cooling.

Choosing this particular thickness balances the need for support and the accessibility of cutting the sections effectively. A wax thickness too thin might not provide enough support, leading to potential stretching or tearing during microtomy, while a thickness too great could hinder precision in slicing the tissue and potentially lead to complications in achieving clear sections. Thus, a coating of around 2 mm is ideal for good performance in histopathologic techniques.