The study sample included 66 freshly extracted permanent teeth obtained as discarded waste from dental office patients. Physical and microscopic findings were evaluated in relation to temperature and duration of thermal insult. Microscopic examination following decalcification and histologic processing revealed such changes as severe tissue fragmentation, vapor bubbles within dentinal tubules, altered histologic staining, charring, and tissue shrinkage. Dentin appeared to be the most reliable microscopic identifier of incinerated dental tissues. Temperatures above 600 degrees Centigrade strongly predicted tooth disintegration following decalcification. The findings have implications in incineration cases where histologic evidence must be maintained and examined intact. 13 references, 3 tables, and 6 figures