This paper reviews some of the nanoindentation research that has been done on teeth and discusses the usefulness of this technique in studying the structure-property-function relationship at the micro and nanometer scale. In particular, examples on the use of nanoindentation technique in investigating the effects of cleansing and bleaching agents as well as drinks on the micro- and nanostructures and mechanical properties of teeth are highlighted. Although nanoindentation on teeth is a relatively new area of research, it provides an excellent way of probing and relating the structures and mechanical properties of teeth at the submicron and nanometer scales that were previously not possible but which can now greatly benefit dental research. For example, a nanoindenter with a high resolution imaging capability can help to elucidate the mechanisms with which certain diseases can damage and compromise the structural integrity of teeth at the micro- and nanometer scale. With this information, clinicians and researchers can then work towards how best to tackle these problems or even preventing them.