Intra - and inter-examiner reproducibility in constant force probing.

This study evaluated intra- and inter-examiner reproducibility for a conventional manual probe versus a computer-interfaced force-controlled periodontal probe. 2 examiners recorded probing depths (PD) and relative attachment levels (AL) at 1128 sites in 15 periodontal maintenance patients. Each site was evaluated 2x, 7 to 10 days apart by both examiners. Probing force for the electronic probe was 15 g. PD intra-examiner reproducibility (within +/- 1.0 mm) for shallow sites (PD < or = 3 mm) was 98.6% versus 91.5% for the conventional versus the electronic probe for examiner 1 and 98.5% versus 88.7% for examiner 2. Corresponding values for deeper sites (PD > 3 mm) were 96.4% versus 85.9% for examiner 1 and 95.1% versus 77.0% for examiner 2. Generally, AL intra-examiner reproducibility was 1 to 3% lower than for PD. PD inter-examiner reproducibility (within +/- 1.0 mm) was 99.2% versus 90.7% for the conventional versus the electronic probe, respectively, for shallow sites and 95.4% versus 76.9% for deeper sites. AL inter-examiner reproducibility (within +/- 1.0 mm) was 1 to 5% lower than for PD. Both intra- and inter-examiner reproducibility was higher for anterior than for posterior sites. Mean PD and AL were similar for both examiners. However, the electronic probe consistently recorded 0.1 to 0.2 mm higher values than the conventional probe. Standard deviations indicated a greater variability for electronic than for manual probing. The results suggest that intra- and inter-examiner reproducibility may not necessarily be higher with an electronic, force-controlled periodontal probe than with a conventional manual probe.