Ozone can be used for All  the following except:
As ozone is a great sterilization medium.
It is used for:

Disinfection of the root canal during root canal treatment.
Sterilization of tooth surfaces before making fillings or before inserting crowns or inlays.
Disinfection of dental unit  water  lines.
Very fast internal bleaching.
Desensitizing the crown preparations. 

There is a currently only one device that has health and safety executive approval for the treatment of the dental caries in the mouth, and it is named as healozone.
Reference: International Journal of Oral Health and Medical Research | ISSN 2395-7387 | SEPTEMBER-OCTOBER 2015 | VOL 2 | ISSUE 391
Disinfection of the root canal during root canal treatment
Sterilization  of  tooth  surfaces  before  making  fillings  or before inserting crowns or inlays
Prevention of dental caries
Internal  bleaching