enamel

Scientists know a great deal about what enamel looks like. However, they don’t know exactly how it forms. Fortunately, a technique called atom probe tomography now allows researchers to look at the distribution of the various atoms and ions in tooth enamel to see whether there are patterns. The method generates 3D visuals of materials at the atom scale.

Source: http://www.forbes.com/sites/carmendrahl/2016/09/07/nanoscale-view-of-enamel-might-help-us-treat-tooth-decay/#456edbb6d504