Assessment of gingival thickness using an ultrasonic dental system prototype: A comparison to traditional methods

Knowledge of periodontal anatomy is essential when performing surgical and non-surgical procedures in the field of oral healthcare. Gingival thickness (GT) is often assessed for this purpose. A dental system prototype was recently developed for quantitative, non-invasive GT assessment by high-frequency (HF) ultrasound. Laboratory trials were conducted to validate system performance against a traditional method of assessment. A system with a 50 MHz broadband, spherically-focused transducer was used. The transducer was housed in a small, hand-held probe equipped with a continuous water supply. A-scans were obtained and thickness at each location was determined. For comparison, the traditional method of transgingival probing through tissue with an endodontic k-file needle was also implemented. Preliminary experiments were performed on phantoms simulating the anatomical and acoustic properties of human periodontal tissues. A porcine cadaver was obtained for further laboratory trials. The speed of sound through porcine gingiva was determined to be 1564 ± 21 m/s. Finally, a multiple-point experiment involved GT assessment in an array of locations on the buccal gingival surface in the fourth quadrant. Ultrasonic measurements were found to yield similar GT values to those obtained from invasive methods. Results obtained in this experiment validate the applicability of ultrasound as a diagnostic tool for assessing periodontal anatomy.