A Preliminary Investigation into the Accuracy of 3D Modeling and 3D Printing in Forensic Anthropology Evidence Reconstruction,

Abstract

There is currently no published empirical evidence‐base demonstrating 3D printing to be an accurate and reliable tool in forensic anthropology, despite 3D printed replicas being exhibited as demonstrative evidence in court. In this study, human bones (n = 3) scanned using computed tomography were reconstructed as virtual 3D models (n = 6), and 3D printed using six commercially available printers, with osteometric data recorded at each stage. Virtual models and 3D prints were on average accurate to the source bones, with mean differences from −0.4 to 1.2 mm (−0.4% to 12.0%). Interobserver differences ranged from −5.1 to 0.7 mm (−5.3% to 0.7%). Reconstruction and modeling parameters influenced accuracy, and prints produced using selective laser sintering (SLS) were most consistently accurate. This preliminary investigation into virtual modeling and 3D printer capability provides a novel insight into the accuracy of 3D printing osteological samples and begins to establish an evidence‐base for validating 3D printed bones as demonstrative evidence.

Imaging in forensic science: Five years on

“…Additionally, CT scans are influenced by metal artefacts such as gunshot or dental amalgams (Bornik et al 2018), and lastly, samples must be transportable and fit inside the CT gantry. Since the technique images in slices, the quality of the models from CT is limited and affected by the scan resolution, the parameters involved in scan acquisition (Guyomarc'h et al 2012), and the user segmentation procedure (Carew et al 2018).…”

“…The two must be distinguished when presenting 3D virtual scenes and practitioners have a responsibility to ensure that courts of law understand this distinction. Secondly, exhibits used as demonstrative aids or demonstrative evidence must be separated; each have differing rules of admissibility and moreover demonstrative aids are not admitted into evidence and carry no probative value (Carew et al 2018;Hofer 2007).…”

“…3D polygon mesh files (primarily STL) from digital imaging techniques can be translated for a 3D printer to print. There are several different 3D printing techniques available each of which has differing advantages, limitations and considerations based on the sample morphology (Hodgdon et al 2018 andCarew et al 2018). The parameters employed during scanning and post-processing (such as slice thickness or surface smoothing) are crucial to the accuracy and quality of the generated 3D model and subsequent 3D print (Ford andDecker 2016, Guyomarc'h et al 2012).…”

“…The parameters employed during scanning and post-processing (such as slice thickness or surface smoothing) are crucial to the accuracy and quality of the generated 3D model and subsequent 3D print (Ford andDecker 2016, Guyomarc'h et al 2012). The accuracy of a printed replica should not be affected by printer resolution, provided printer resolution is greater than scan resolution (Hodgdon et al 2018 andCarew et al 2018).…”

Morphometric analysis and three-dimensional computed tomography reconstruction of the long bones of femoral and crural regions in Van cats

“…These systems are also being used to obtain osteometric and volumetric measurement results, to evaluate any potential developmental, metabolic, inflammatory, or degenerative anomalies, and to investigate numerous other pathological situations like traumas, dislocations, fractures, or neoplasia [26,45]. Anthropological studies also commonly use these methods and 3D modeling in tandem to determine the morphological properties of long bones and to perform various measurements on them [8,17,21].…”