In vitro investigation of heat transfer in human tooth

The understanding of heat transfer in human teeth is important for optimizing clinical practice protocols and daily intake instructions. However, it is technically challenging to study the in vitro thermal behavior of human tooth due to its small size and complex biological/geometrical structure. The currently widely used method is based on thermocouples, which has several limitations such as low spatial resolution, contact measurement and, in particular, lack of whole-field information. To address these challenges, an experimental system was developed to measure the whole-field temperature distribution in human tooth in vitro. The human tooth sample was heated at the tooth crown with flowing hot water (60 °C) for 10 s and then cooled down by natural convection of air. The temperature of the whole sectioned sample surface was recorded using an infrared camera. The results demonstrate that the developed system is capable of measuring temperature evolution in small human tooth samples. The biological junction of tooth (e.g., dental-enamel junction) is shown to have great influence on its heat transfer behavior. The present study could open the door for several future applications, e.g., systemic investigation of heat transfer in intact/restored tooth heated with clinical methods for treatment optimization, and measurement of thermal properties for different tooth layers.