Nanoindentation and storage of teeth.

This study determined changes in nanomechanical properties of dentin and enamel during storage in deionized water, calcium chloride buffered saline solution and Hank's balanced salts solution (HBSS). Atomic force microscopy based nanoindentation showed that storing teeth in deionized water or CaCl(2)-solution resulted in a large decrease in elastic modulus and hardness. At 1 day a decrease in the mechanical properties values of up to 20% and 30% was observed for enamel and dentin, respectively. After 1 week, mechanical properties dropped below 50% of their starting values, which is attributed to a demineralization process during storage. In contrast, storing teeth in HBSS did not significantly alter the mechanical properties for a time interval of 2 weeks. The use of HBSS for storage of samples from teeth is recommended.