1.Validity of Three-dimensional Facial Scan Taken with Facial Scanner and Digital Photo Wrapping on the Cone-beam Computed Tomography: Comparison of Soft Tissue Parameters
Hussein ALJAWAD ; Kyungmin Clara LEE
Journal of Korean Dental Science 2022;15(1):19-30
Purpose:
The purpose of the study was to assess the validity of three-dimensional (3D) facial scan taken with facial scanner and digital photo wrapping on the cone-beam computed tomography (CBCT).
Materials and Methods:
Twenty-five patients had their CBCT scan, two-dimensional (2D) standardized frontal photographs and 3D facial scan obtained on the same day. The facial scans were taken with a facial scanner in an upright position. The 2D standardized frontal photographs were taken at a fixed distance from patients using a camera fixed to a cephalometric apparatus. The 2D integrated facial models were created using digital photo wrapping of frontal photographs on the corresponding CBCT images. The 3D integrated facial models were created using the integration process of 3D facial scans on the CBCT images. On the integrated facial models, sixteen soft tissue landmarks were identified, and the vertical, horizontal, oblique and angular distances between soft tissue landmarks were compared among the 2D facial models and 3D facial models, and CBCT images.Result: The results showed no significant differences of linear and angular measurements among CBCT images, 2D and 3D facial models except for Se-Sn vertical linear measurement which showed significant difference for the 3D facial models. The Bland–Altman plots showed that all measurements were within the limit of agreement. For 3D facial model, all Bland–Altman plots showed that systematic bias was less than 2.0 mm and 2.0° except for Se-Sn linear vertical measurement. For 2D facial model, the Bland-Altman plots of 6 out of 11 of the angular measurements showed systematic bias of more than 2.0°.
Conclusion
The facial scan taken with facial scanner showed a clinically acceptable performance. The digital 2D photo wrapping has limitations in clinical use compared to 3D facial scans.
2.Accuracy of virtual 3-dimensional cephalometric images constructed with 2-dimensional cephalograms using the biplanar radiography principle
Jae-Seo LEE ; Sang-Rok KIM ; Hyeon-Shik HWANG ; Kyungmin Clara LEE
Imaging Science in Dentistry 2021;51(4):407-412
Purpose:
The purpose of this study was to evaluate the accuracy of virtual 3-dimensional (3D) cephalograms constructed using the principle of biplanar radiography by comparing them with cone-beam computed tomography (CBCT) images.
Materials and Methods:
Thirty orthodontic patients were enrolled in this study. Frontal and lateral cephalograms were obtained with the use of a head posture aligner and reconstructed into 3D cephalograms using biplanar radiography software. Thirty-four measurements representing the height, width, depth, and oblique distance were computed in 3 dimensions, and compared with the measurements from the 3D images obtained by CBCT, using the paired t-test and Bland-Altman analysis.
Results:
Comparison of height, width, depth, and oblique measurements showed no statistically significant differences between the measurements obtained from 3D cephalograms and those from CBCT images (P>0.05).Bland-Altman plots also showed high agreement between the 3D cephalograms and CBCT images.
Conclusion
Accurate 3D cephalograms can be constructed using the principle of biplanar radiography if frontal and lateral cephalograms can be obtained with a head posture aligner. Three-dimensional cephalograms generated using biplanar radiography can replace CBCT images taken for diagnostic purposes.
3.3D Facial Scanners: How to Make the Right Choice for Orthodontists
Young-Soo SEO ; Do-Gil KIM ; Gye-Hyeong LEE ; Kyungmin Clara LEE
Journal of Korean Dental Science 2024;17(1):1-13
With the advances of digital scanning technology in dentistry, the interests in facial scanning in orthodontics have increased.There are many different manufacturers of facial scanners marketing to the dental practice. How do you know which one will work best for you? What questions should you be asking? We suggest a clinical guideline which may help you make an informed decision when choosing facial scanners. The characteristics of 7 facial scanners were discussed in this article. Here are some considerations for choosing a facial scanner. *Accuracy: For facial scanners to be of real value, having an appropriate camera resolution is necessary to achieve more accurate facial image representation. For orthodontic application, the scanner must create an accurate representation of an entire face. *Ease of Use: Scanner-related issues that impact their ease of use include type of light; scan type; scan time; file type generated by the scanner; unit size and foot print; and acceptance of scans by third-party providers. *Cost: Most of the expenses associated with facial scanning involve the fixed cost of purchase and maintenance. Other expenses include technical support, warranty costs, transmission fees, and supply costs. This article suggests a clinical guideline to make the right choice for facial scanner in orthodontics.