Forensic dental identification has employed traditionally 2D digital radiological imaging techniques. More recently, 3D cone beam computer tomography (CBCT) data, widely applied in clinical dentistry, have been gradually used. The purpose of this study was to compare the precision and quality of 2D digital orthopantomogram (OPG) and 2D OPG images generated from cone beam computed tomography (CBCT). The study sample consisted of 50 patients with archived conventional 2D OPG and 3D CBCT images. Patients signed an informed consent form to take part in our study. Measurements of the mandible, teeth and dental restorations were taken by two observers on calibrated 2D OPG and 3D CBCT-to-OPG images using measurement functionalities of DOPLHIN software. Acquired dimensions were compared side by side and images of fillings were superimposed. For better visual comparison and more efficient image registration, the methods of spline interpolation were used. The pairs of absolute measurements obtained from conventional OPG and CBCT-to-OPG-converted images were highly correlated (p < 0.05). However, larger, and horizontally measured distances were revealed to be more affected than shorter vertically taken measurements. In relative terms, CBCT-generated width/length indices of the canines and the first molars ranged from 84% to 99.8% of those acquired from traditional OPGs. In addition, corresponding points on the teeth and fillings were compared side by side and in superimposition. The average coincidence of images was 6.1%. The results revealed that for selected metric variables 2D OPGs and 3D CBCT-generated OPGs were complementary and could be used for forensic comparisons.
- MeSH
- digitální zubní radiografie metody MeSH
- lidé MeSH
- mandibula MeSH
- počítačová tomografie s kuželovým svazkem metody MeSH
- rentgendiagnostika panoramatická metody MeSH
- senzitivita a specificita MeSH
- soudní stomatologie * metody MeSH
- trvalá zubní náhrada MeSH
- zuby MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
- MeSH
- lidé MeSH
- mezioborová komunikace MeSH
- oběti zločinu MeSH
- soudní antropologie * MeSH
- soudní stomatologie MeSH
- tělesné pozůstatky MeSH
- zuby * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- rozhovory MeSH
3D Multislice and Cone-beam computed tomography (CBCT) in forensic odontology has been shown to be useful not only in terms of one or a few of dead bodies but also in multiple fatality incidents. 3D Multislice and Cone-beam computed tomography and digital radiography were demonstrated in a forensic examination form. 3D images of the skull and teeth were analysed and validated for long ante mortem/post mortem intervals. The image acquisition was instantaneous; the images were able to be optically enlarged, measured, superimposed and compared prima vista or using special software and exported as a file. Digital radiology and computer tomography has been shown to be important both in common criminalistics practices and in multiple fatality incidents. Our study demonstrated that CBCT imaging offers less image artifacts, low image reconstruction times, mobility of the unit and considerably lower equipment cost.
Superimposition is an efficient method for evaluation of coincidence between a skull and a photo portrait. The principle of superimposition method lies in the projection of the skull into the face image. During the projection of an object with a perspective camera, the mapping of a three-dimensional object into a two-dimensional image takes place. The acquired images of the same object are more or less distorted due to various photographic conditions, due to extrinsic and intrinsic parameters of the camera. The distortions have important influence onto reliability of human identification by the superimposition method. Mathematically we can describe most of the distortions. On the basis of the description the divergences could be simulated and in some cases eliminated by geometric transformation of the compared images. We are presenting a mathematical model of the standard projective camera and the mathematical description of distortions which are important for the superimposition process. The results show the distortions and the elimination of the distortions by means of the projection model.
