Acoustic microscopy in orthodontology

Aim. Assessment of the possibility to use the method of ultrasound acoustic microscopy to control the state of microstructure of hard tooth tissues under the brackets. Methods. The study was conducted with the use of scanning acoustic microscope ELSAM (Leitz, Germany) in Emanuel Institute of biochemical physics, Moscow. The studied material for acoustic microscopy corresponds to 34 teeth (premolars) with brackets fixed to them, which were removed due to orthodontic indications at different time points after brackets placement. Results. In most cases on acoustic images of the removed teeth there were no revealed changes of physical and mechanical enamel properties, fissures or excess porosity both directly under the brackets and in the areas adjacent to the sealer margin. But in some cases along with good enamel state after long-term brackets placement minor changes in the structure of hard tooth tissues were revealed. In particular, the method of acoustic microscopy allowed to detect in the tooth enamel such minor defects as fissures and areas of reduced mineralization and increased porosity. Conclusion. Acoustic microscopy as a novel method to obtain clear structural images of hard tooth tissue state allows detecting minimal changes of the structure of hard tissues and performing medical interventions based on them.