Clinical Periodontal Diagnosis: Probing

Periodontal pocketing, attachment loss, bone loss, and subgingival inflammation are among the clinical signs of periodontitis. Periodontal pockets and subgingival inflammation give evidence of actual periodontal infection, whereas attachment loss and bone loss are symptoms of former periodontitis that has caused tissue destruction in the past. Several clinical or radiographic methods are used to score periodontal pockets, attachment loss, bone loss, and subgingival inflammation and to assess the degree of periodontal destruction. Assessment of the different diagnostic parameters at the same site at different points in time provides information on progression of the disease or the results of local treatment. For judgment and interpretation of the different periodontal parameters it has to be kept in mind that parameters, which are used to evaluate periodontal pockets, attachment loss, bone loss, and subgingival inflammation are diagnostic tests. These tests attempt to assess an anatomic or pathologic reality by using as simple, practicable, and least invasive a method as possible. However, tests often fail to reflect reality perfectly. Further, diagnostic tests exhibit measurement errors that have to be considered for interpretation. Test methods, diagnostic tests, and parameters can be judged according to intra-individual as well as inter-individual reproducibility and validity. Inter-individual reproducibility describes to what extent the results of a test are influenced by the examiner. Intra-individual reproducibility represents the safety with which a repeated measurement by the same examiner will provide identical results. Validity (accuracy) describes how sufficiently a test or examination method represents the anatomical or pathological reality that is to be assessed.