Ultrasonic Characterization of Human Dentine

Dentine structure is unique and complex in nature and has the ability to undergo physiological and non-physiological structural changes due to age process or disease. Ultrasound is safe, fast and non-invasive technique. In the last decade, the popularity of the technique has increased in dental field. Several researchers used the technique to investigate hard and soft dental tissues. Limited reported data is available for ultrasonic characterization of human dentine. Such studies would provide baseline information for the assessment of structural changes in human dentine using ultrasound. Therefore, the aim of this study was to investigate normal human dentine using ultrasonic technique and scanning electron microscopy (SEM). Dentine samples were prepared from extracted impacted molars. Ultrasonic measurements were carried out on dentine samples using broadband ultrasonic attenuation and time-of-flight to measure attenuation and velocity of ultrasonic wave, respectively. A number of validation experiments were performed prior to conducting ultrasonic measurements on dentine samples. After ultrasonic measurements, dentine samples were examined under SEM. Ultrasonic measurements of ultrasonic wave velocity using WaveStar software showed that wave velocity in dentine samples was 3900±24m/s. Whereas, ultrasonic measurements of ultrasonic wave attenuation were unfeasible to measure in dentine samples. SEM examinations of dentine samples demonstrated that dentine structure is characterized by open dentinal tubules distributed all over the sample.