Three-Dimensional Reconstruction and Visualization of Human Enamel Ex Vivo Using High-Frequency Ultrasound

Dental decay and erosion are common cases in clinics. It would be useful for dentists to collect adequate information about the thickness of hard tissue (e.g., enamel and dentin) during treatment without pulp exposure. This study proposes a scanning system that collects structural information of the tooth surface and enamel-dentine junction. A three-dimensional (3D) motorized scanning stage is used to control the movement trajectories of an A-mode transducer to acquire echoes from the surface of a tooth. The 3D form of enamel is reconstructed using this system. By adopting a gain compensation method for radio-frequency signals, no special preparation is required before scanning. Despite some discontinuous areas in the 3D images, the 3D representations of human molars well duplicated the real samples and the thickness of enamel could be measured. Based on micro-computed tomography data, the overall measurement error of the proposed system is 3.55%, indicating good performance for clinical application.