CPITN--interpretations and limitations

As with all indices which impose numerical scales on a biological process, there are limitations with CPITN which must be identified and recognised. The limitations are due to the index being used for purposes for which it was not originally designed and recent advances in understanding which question the underlying assumptions of the index. Whilst questioning whether these limitations are sufficient to abandon the CPITN in favour of a new index, suggestions are made for modifications to the existing system. These include, the recording of each of the clinical indicators separately, as well as including the measurement of total loss of attachment. In addition an extension of the treatment need scale from four to five points is suggested.