O’Learly plaque index
- Dry teeth
- Apply disclosing solution with cotton tip applicator
- Rinse once
- Older plaque appears darker in color (blue)
- Examine each tooth surface and record plaque on surfaces along the cervical 1/3rd of the tooth.
- Compute PI score
- Count number of surfaces with plaque (numerator)
- Determine the total number of surfaces available (# of teeth X 4) (denominator)
- PI = (# of surfaces with plaque X 100) / (Total # of available surfaces)
- PI of less than or equal to 10% is recommended.