Photoacoustic tomography versus cone-beam computed tomography versus micro-computed tomography: Accuracy of 3D reconstructions of human teeth

• Published in: PloS one Vol. 17; no. 12; p. e0274818
• Main Authors: Schneider, Sonja Jasmin Maria, Höhne, Christian, Schneider, Martin, Schmitter, Marc
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 19.12.2022; Public Library of Science (PLoS)
• Subjects: Accuracy; Biology and Life Sciences; Cementum; Comparative analysis; Computed tomography; Computer and Information Sciences; Cone-Beam Computed Tomography - methods; Data analysis; Dental caries; Dental pulp; Dental roots; Engineering and Technology; Humans; Image acquisition; Image analysis; Image contrast; Image processing; Image Processing, Computer-Assisted; Image quality; Image reconstruction; Imaging techniques; Imaging, Three-Dimensional - methods; Incisor; Incisors; Magnetic resonance imaging; Medical examination; Medical imaging; Medicine and Health Sciences; Methods; Periodontitis; Photoacoustic effect; Research and Analysis Methods; Software; Standard deviation; Teeth; Three dimensional imaging; Three dimensional models; Tomography; Trauma; Wavelength; Wavelengths; X-Ray Microtomography; Germany; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0274818

In this in-vitro study, teeth were imaged using photoacoustic tomography (PAT), cone-beam computed tomography (CBCT), and micro-computed tomography (μ-CT). The study had aim: to identify the best wavelength for PAT images to determine the accuracy of the three imaging methods, and to determine whether PAT images of teeth can achieve acceptable reconstruction quality. Nineteen human mandibular single-rooted incisors were extracted from patients with trauma or periodontitis. To determine the best wavelength for acquiring photoacoustic images, all 19 teeth were scanned in vitro with PAT, using different laser wavelengths between 680 and 960 nm. The images were analyzed using image analysis software. To assess the accuracy of PAT and compare it with the accuracy of CBCT, each tooth was also scanned in vitro using CBCT and the reference standard technique of μ-CT. Subsequently, three different three-dimensional models, one for each imaging technique, were created for each tooth. Finally, the three different three-dimensional models acquired for the same tooth were matched and analyzed regarding volume and surface. The highest quality tooth images were achieved using the 680 nm wavelength, which showed the best contrast ratio. The full geometry of the dental root (μ-CT compared with PAT) could be visualized with relative standard deviations of 0.12 mm for the surface and -7.33 mm3 for the volume (n = 19). The full geometry of the dental root (μ-CT compared with CBCT) could be visualized with relative standard deviations of 0.06 mm for the surface and -14.56 mm3 for the volume (n = 19). The difference between the PAT-μ-CT group and CBCT-μ-CT group regarding the total average of the root surface area was not significant (p>0.06). Images, which were acquired using PAT at 680nm showed the best contrast ration, enabling the identification of dentin, cementum and the dental pulp. No significant differences were found between the PAT-μ-CT group and CBCT-μ-CT group regarding the total average of the RSA and the total volume. Thus, three-dimensional reconstructions based on in-vitro PAT are already of acceptable reconstruction quality.