Thermal Conductivity of Tooth Structure, Dental Cements, and Amalgam

¹ School of Dentistry, University of Michigan, Ann Arbor, Michigan

The thermal conductivity of human dentin, enamel, zinc phosphate cement, silicate cement, and dental amalgram has been determined by using an improved steady-state procedure.

The average thermal conductivity of dentin was 1.36-1.39 x 10^-3 cal/sec/cm²/°C/ cm, which was lower than the value of 2.23 x 10^-3 for human enamel.

Zinc phosphate and silicate cements had conductivities of 2.5-3.1 x 10^-3 and 1.78- 1.86 x 10^-3 cal/sec/cm²/°C/cm, respectively. These values approximate the value for tooth structure and are in the range of good thermal insulators.

Dental amalgam had an average conductivity of 5.4 x 10^-2 cal/sec/cm²/°C/cm, which places it as a relatively poor insulator compared with tooth structure or dental cements, but a relatively good insulator compared with dental gold alloys.