8 - Heat-Related Changes in Tooth Color: Temperature Versus Duration of Exposure

Abstract

This chapter discusses the heat-related changes in tooth color. The teeth are extracted during routine dental procedures and placed immediately into a saline solution to prevent dehydration. Before heat alterations are conducted, the teeth are individually cleaned of any adhering soft tissue using dental tools and tap water. Once the teeth are processed they are returned to the saline solution until experimentation can begin. The gross morphological changes and the effects of dehydration are observed after the teeth cool to room temperature. The teeth first turn black and/or brown. These colors then give way to blues and grays, which are eventually replaced with white. The teeth are weighed on a digital scale accurate to 0.1 g. They are then placed in a BLUE M TM Lab-Heat muffle furnace where the temperature is constant for the entire duration of their heat exposure. The results show that major color changes occur in specimens incinerated at 260 °C (500 °F) for 30 min. The enamel exhibits a very pale brown (10 yr 8/2) color. The dentin exhibits the greatest amount of change turning a dark reddish brown (2.5 yr 2.5/3) color.