For the enamel and dentin of porcine primary molar teeth, the spatial variability of the elements and chemical groups was studied with the aim of identifying the chemistry of porcine teeth, and it was then compared with results for human primary teeth. Porcine teeth were taken from specially bred animals.An electron microprobe was applied for the elemental analyses and a Raman microscope for the determination of chemical groups. The distribution of the main elements (Ca, P) was similar for both porcine and human teeth, whereas major differences were found in the distributions of minor elements (Mg, Sr, Cl, C). Carbonates were present in porcine dentin mainly as A-substituted species, whereas the B-substituted ones prevailed in enamel. The mechanism of asymmetric enrichment of Ca and P was quantitatively calculated as a consequence of Mg release. The layer close to the surface of the enamel with air had a unique composition. Cl involvement in enamel close to the boundary with air is a complex process, coupled with the involvement of Sr and release of Mg. The discoveries shed light on the role of elements in apatites, especially the role of carbonates and magnesium in porcine teeth, and put in doubt the potential use of pig apatite as a substitute for human apatite in filling materials.