**3. Diagnostic methods**

It is very important to detect enamel demineralizations associated with orthodontic treatment at an early stage. Pitts [12] stated that the tools and methods used in the diagnosis of caries lesion should be easy to apply, reliable, reproducible, and noninvasive.

Diagnostic methods can be classified as follows [13]:

1.Traditional methods: visual inspection, Sonde examination, and radiographic examination.

