Reliability of probing depth assessments at healthy implant sites and natural teeth

Aim To evaluate the intra- and inter-examiner reliability in the assessment of probing depth (PD) measurements at healthy dental implant sites and periodontally healthy natural teeth. Materials and methods Five patients exhibiting 21 dental implants were enrolled in the study. Eight experienced examiners performed duplicate PD measurements at six sites of all implants and of preselected natural teeth. Intra-examiner accuracy was estimated using intra-examiner correlation coefficients (ICCs) with 95% confidence intervals (CI). A gold standard (GS) examiner was set. Inter-examiner accuracy compared to the GS examiner was assessed using pairwise inter-examiner ICCs. Results The intra-examiner ICC ranged from 0.759 (95% CI, 0.692–0.812) to 0.863 (95% CI, 0.826–0.892) for the measurements at teeth and from 0.712 (95% CI, 0.580–0.800) to 0.841 (95% CI, 0.774–0.888) for the PDs assessed at implants. The inter-examiner ICCs for tooth measurements varied from 0.197 (95% CI, − 0.280 to 0.511) to 0.791 (95% CI, 0.560–0.892). The corresponding values for the assessments at implants varied from 0.576 (95% CI, 0.286–0.734) to 0.794 (95% CI, 0.708–0.855). Conclusions The intra- and inter-examiner reproducibility of repeated PD measurements assessed by experienced examiners tended to be higher for the measurements at periodontally healthy teeth compared to healthy dental implant sites. Clinical relevance Experienced examiners demonstrated a higher degree of reliability of probing measurements around teeth compared to dental implants.