27 April 2022

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Inter-examiner concordance in periodontal clinical parameters measurements

Authors: Stefano Corbella, Flavio Grimolizzi, Beatrice Zotti, Alice Alberti, Luca Francetti

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The term “periodontal disease” define a group of problems affecting the tissues surrounding the tooth, which induce gingival bleeding and retraction of soft tis- sues and may result in bone loss due to inflammation induced by bacteria contamination. The diagnosis of the disease and its grade of severity is based on the evaluation of clinical parameters such as probing depth (PD), clinical attachment level (CAL) and recession (REC). As previously demonstrated in several in vitro and in vivo studies, reproducibility of the measurements of the probing depth is

dependent on the examiner’s abilities and experience. The purpose of this comparative study is to evaluate the consistency and reproducibility of the measurements detected by two examiners with different levels of experience in patients with periodontitis.

MATERIALS AND METHODS
The study was conducted on 25 patients. All measurements were taken on the right jaw for a minimum of 36 probing sites for each subject included in the research. The same teeth were alternately examined and evaluated by two operators and the order for the examination was randomly determined based on a table generated by a computer. The probing was performed with a North Carolina periodontal probe and the following parameters were recorded: PD, REC, furcation and mobility. The two operators were an experienced dentist with ten- year experience in periodontology (SC) and a dental hygienist (FG) with a year of experience in periodontology.

RESULTS
The Cohen’s Kappa showed a fair agreement (0.376) in the identification of sites with probing depth equal or higher than 4 mm, and a moderate agreement in the identification of teeth with at least one site with probing depth equal or higher than 4 mm.

CONCLUSIONS
The present study showed the presence of discrepancies in probing results when two operators with different experience and background evaluate the same periodontal site. The reproducibility of periodontal evaluation has been studied in several in vivo and in vitro researches, however, no studies are completely superimposable to the present work. The importance of a careful calibration process in order to increase the reproducibility of the periodontal evaluation was highlighted in the study published by Andrade et al. in 2012. The authors affirmed that the reproducibility of the results could be mostly influenced by the previous calibration of the operators and the exercise more than the operators’ experience. This result can be considered as a partial confirmation of the results obtained in our study, where the relatively poor reproducibility of the results can be explained by the absence of calibration. However, these findings are in contrast with that obtained by other authors that considered operators experience the key factor to obtain reproducible measurements. To conclude, only moderate accordance could be obtained for both PD and CAL values when two operators with different levels of experience are considered.

CLINICAL SIGNIFICANCE
The study showed that it is difficult to obtain a complete accordance in the periodontal parameters evaluation when two differ- ent experienced operators are selected. A calibration period can be considered necessary in order to obtain reproducible measurements for PD and CAL. More randomized clinical trials should consider the effects of calibration methods on reproducibility of clinical parameters measurement.