Periodontal ultrasonography

OBJECTIVES: The aim of this study was to investigate high-frequency ultrasound imaging for periodontal assessment. MATERIAL AND METHODS: A newly developed ultrasonic scanner with a frequency of 20 MHz was used. Pig jaws were selected as the experimental model. Three teeth per jaw were imaged with the scanner and duplicate measurements were made of the distance from a fixed landmark on the teeth to the alveolar bone crest. These measurements were compared to transgingival and direct measurements of the same teeth following reflection of the soft tissues. One further jaw was used for histological comparison with the ultrasound image. RESULTS: Using ultrasonography, it was possible to image the main periodontal structures. The ultrasound measurements showed better repeatability than either of the other two methods (repeatability coefficient: 0.44 mm for ultrasound, 0.93 mm for transgingival probing and 0.6 mm for direct measurements). Also, ultrasound was in better agreement with direct, open probing measurements (0.004 +/- 0.58 mm) than transgingival probing with direct measurements (0 +/- 0.7 mm). CONCLUSIONS: Ultrasonography provides a highly accurate and repeatable technique for periodontal assessment in this model.