Inter- and intra-examiner variability using standard and constant force periodontal probes

Current methods of measuring periodontal probing depths at specified sites by clinical means are subject to wide variation both within and between examiners. This paper reports an investigation into the influence of a constant-force periodontal probe on intra- and inter-examiner variability when measuring probing depths. 30 sites in 10 patients with untreated chronic adult type periodontitis were examined by 2 operators, firstly using a standard periodontal pocket probe then with a constant force probe. Neither examiner was aware of the others readings and were thus blind in relation to one another. Comparison of the recordings of the 2 operators using the standard probes showed significant differences between the operators (p less than 0.01) but this difference became insignificant when the constant force probe was used. One operator had a significant variation between his standard and constant force measurements (p less than 0.01), but the other did not. Overall there was a maximum variation of +/- 1 mm in 79.9% of recordings using the standard probe and this agreement was increased to 100% with the use of the constant pressure probe.