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bioRxiv · 10.1101/2022.03.31.486598

Characterization of a miniaturized ultrasound transducer customized for oral health applications

Qi, B.·Hariri, A.·Khazaeinezhad, R.·Fu, L.·Jokerst, J. V.
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Abstract

ObjectiveTo customize a miniaturized ultrasound transducer to access full-mouth B-mode, color Doppler and spectral Doppler imaging for monitoring oral health. MethodsA customized periodontal ultrasound transducer SS-19-128 (19 MHz, 128 channels) with 1.8 cm wide and 1 cm thick was developed and connected to a data acquisition (DAQ) system. B-mode, color Doppler, and spectral Doppler data could all be collected with SS-19-128. The imaging resolution and penetration capacity of SS-19-128 were characterized on phantoms. Five human subjects were recruited to demonstrate B-mode and Doppler imaging by SS-19-128. Gingival thickness was measured on 11 swine teeth by SS-19-128 for comparison to conventional transgingival probing via Bland-Altman analysis and Pearson correlation. ResultsThe axial and lateral spatial resolution at 5.5 mm depth is 102.1 m and 142.9 m, respectively. The penetration depth in a tissue-mimicking phantom is over 30 mm. In vivo B-mode imaging of all 28 teeth was demonstrated on one human subject, and imaging of tooth #18 was accessed on five human subjects. Gingival thickness measurement compared with transgingival probing showed a bias of -0.015 mm and SD of 0.031 mm, and a r = 0.9235 (P<0.0001) correlation. In vivo color and spectral Doppler imaging of the supraperiosteal artery in human gingiva was performed to generate hemodynamic information. ConclusionsThe small size of SS-19-128 offers important advantages over existing technology--more specifically, whole-mouth scanning/charting reminiscent of radiography. This is nearly a two-fold increase in the number of teeth that can be assessed versus existing transducers.

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Qi, B., Hariri, A., Khazaeinezhad, R., Fu, L., Jokerst, J. V.. 2022-04-01. Characterization of a miniaturized ultrasound transducer customized for oral health applications. https://doi.org/10.1101/2022.03.31.486598

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