The 104 human permanent mandibular canines in this study were collected from university medical centers in southwest Germany and Switzerland. All included teeth were extracted for reasons unrelated to the study and are so-called excess material. The teeth were used under irreversibly anonymized conditions and in accordance with the Federal Act on Research involving Human Beings (Human Research Act [@https://www.admin.ch/opc/en/classified-compilation/20061313/index.html]). All donors were adults and gave written informed consent for research purposes. This makes an ethics approval unnecessary for the purpose of this investigation.
Two tooth datasets are available to download in the GitHub repository with the analysis notebook: https://github.com/habi/zmk-tooth-cohort [@doi:10.5281/zenodo.3999402]. The other datasets used for the current study are available from the corresponding author on reasonable request.
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
DH scanned the teeth, wrote the analysis notebook and the original draft of the manuscript. RH contributed with discussion during the development of the method and reviewed the manuscript. TGW contributed with ideas and discussion for developing the method, discussed the results, edited and reviewed the manuscript. All authors read and approved the final manuscript.
We thank Oleksiy-Zakhar Khoma (Institute of Anatomy, University of Bern, Switzerland) for designing the sample holder that we used for scanning the teeth. We thank Jennifer Fazzari (Institute of Anatomy, University of Bern, Switzerland) for proof-reading the manuscript. We thank Andrea Anderegg and Michael Stiebritz (both Department of Restorative, Preventive and Pediatric Dentistry, School of Dental Medicine, University of Bern, Switzerland) and Valentin Djonov (Institute of Anatomy, University of Bern, Switzerland) for their kind support.