De tec tion and moni tor ing of the com plex pro cess of dem in er ali zation and re min er ali sa tion by the den tal car ies is a den tist’s chal lenge. Even car ies start ing as a sub sur face dem in er ali za tion of enamel, may prog ress to the un der ly ing den tine and, even tu ally, to cavi ta tion of the sur face [14]. Ac cu rate di ag no sis be fore cavi ta tion oc curs would per mit tar geted pre ven tive treat ment, thereby sig nifi cantly im prov ing den tal health and re duc ing the need for ex pen sive drill ing and fill ing [10]. Con ven tional di ag nos tic meth ods in volv ing vis ual in spec tion and the use of sharp den tal ex plorer tools de pend on sub jec tive clini cal crite ria such as color, tex ture, soft ness and re sis tance to re moval. These meth ods are good for the de tec tion of larger or cavi tated le sions. How ever, they are not suit able for the de tec tion of early den tal car ies be cause of poor sen si tiv ity and speci fic ity. Rou tine den tal ra dio graphs also lack the abil ity to de tect early cari ous lesions on enamel sur face. Ap proxi mately 30-40% min eral loss is nec es sary be fore ra dio graphs can de tect the cari ous le sion. It can take a few months or longer for this ex tent of dem in er ali za tion. There fore, bet ter di ag nos tic tools are needed to de tect early cari ous le sions and help pre vent dental cavi ties. Over the last years, vari ous tech niques have been ex plored to ad dress the need for bet ter de tec tion tools to di ag nose early den tal car ies. These tech niques in