Time wears on: assessing how bone wears using 3D surface texture analysis (r script and stan model files)

An experiment was undertaken with the intention of understanding the basics of use-wear formation over time by taking incremental impressions of bone specimens subjected to a controlled, mechanical experiment. This study assessed how bone wears during extended use on three materials (processed leather, fresh skin, or dry bark), from three initial surface modification states (unmodified, scraped with flint, or ground with sandstone). Data obtained from a confocal disc-scanning microscope was then applied to 3D surface texture analysis using ISO 25178 parameters: surface roughness [Sa], peak curvature [Spc], autocorrelation length [Sal], and upper material ratio [Smr1]. Additional 3D surface texture parameters from the experimental specimens are also recorded here. Other data is recorded here including specimen ID, amount of time used, location of scan, sample type, whether the sample is the terminus of the experiment and if a surface mold was taken at the end of the experiment, whether the sample was rescanned after one year, material type used, manufacturing type at start of experiment, which lot of the bone specimens were acquired in, state of bone, and sampling method.