Chapter 7 - Heat-Related Changes in Tooth Color

Abstract

This chapter discusses the heat-related changes in tooth colour. The teeth used in the study were extracted during routine dental procedures and placed immediately into a saline solution to prevent dehydration. Before heat alterations were performed, the teeth were individually cleaned of any adhering soft tissue using dental tools and tap water. Once the teeth were processed, they were returned to the saline solution until experimentation began. To observe heat-induced changes in colour and morphology, the teeth were exposed to constant temperatures for 30- or 60-min intervals in a BLUE M™ Lab-Heat muffle furnace. After the teeth were allowed to cool to room temperature, the gross morphological changes and the effects of heat-induced dehydration were observed. The teeth were then weighed on a digital scale accurate to 0.1g. Results showed that the first major colour changes occurred in specimens incinerated at 260°C (500°F) for 30minutes. The enamel exhibited a very pale brown (10YR 8/2) colour. The dentin exhibited the greatest amount of change, turning a dark reddish brown (2.5YR 2.5/3) colour. The teeth first turned black and/or brown. These colours then gave way to blues and greys, which were eventually replaced with white.