I am trying to see the cementum layers in tooth sections from Australian fur seals, for purposes of aging. I have tried the standard methods:  1. taking a 200 micron section on a circular saw and viewing with transmitted polarised light, 2. decalcification with RDO, 10 micron sectioning on a microtome, and staining with Haemotoxylin. Neither method has produced good results. 

My samples have been stored in a mixture of 70% ethanol and glycerin for 30 years.

My question is: Could my samples have become degraded through being stored in this way? Are there any other suggestions?

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BRUCE ABALOZ                           PH:61383446282
HISTOLOGIST                            FAX:61383447909 
DEPT.of ZOOLOGY                        EMAIL: brucea@unimelb.edu.au
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