Traditional methods for age determination of wildlife include either slicing thin sections off or grinding a tooth, both of which are laborious and invasive. Especially when it comes to ancient and valuable museum samples of rare or extinct species, non-invasive methods are preferable. In this study, X-ray micro-computed tomography (µ-CT) was verified as an alternative non-invasive method for age determination of three species within the order of Carnivora and suborders Odontoceti. Teeth from 13 red foxes (Vulpes vulpes), 2 American mink (Neogale vison), and 2 harbor porpoises (Phocoena phocoena) of known age were studied using µ-CT. The number of visible dental growth layers in the µ-CT were highly correlated with true age for all three species (R² = 96%, p < 0.001). In addition, the Bland–Altman plot showed high agreement between the age of individuals and visible dental layers represented in 2D slices of the 3D µ-CT images. The true age of individuals was on average 0.3 (±0.6 SD) years higher than the age interpreted by the µ-CT image, and there was a 95% agreement between the true age and the age interpreted from visible dental layers in the µ-CT.

An increasing number of industrial sectors are considering the potential of additive manufacturing as an asset to improve their production. Indeed, additive manufacturing enables the fabrication of very complex geometries and inner cavities that cannot be manufactured with conventional techniques. However, in critical sectors such as aerospace, defence and medical, the parts need to be certified, which requires parts to be non-destructively characterised in terms of flaws, geometry and dimensional accuracy. X-ray computed tomography is the only current 3D volumetric technique, which is suited for the non-destructive analysis of internal flaws, geometry and measurements of internal dimensions and roughness. However, regardless of its huge potential, Xray computed tomography is not as mature a technology for dimensional metrology as compared to conventional tactile coordinate measuring machines. In most cases there is no traceability to SI units in the dimensional domain. Recently, numerous reference standards (i.e. physical artefacts) addressing X-ray computed tomography dimensional accuracy have been published, but they do not necessarily address the calibration of XCT system in connection with AM parts. In this work, a new and improved standard in three different materials has been designed with a dual purpose: Fully calibrating X-ray computed tomography for dimensional measurements while being representative of additively manufactured parts in terms of flaws and material, meeting the needs of the industry. These standards will be used to metrologically validate X-ray computed tomography for the inspection of additively manufactured parts.