Preferred Reporting Items for Diagnostic Accuracy Studies in Endodontics (PRIDASE) guidelines: a development protocol

Diagnostic accuracy studies play an important role in informing clinical practice and patient management, by evaluating the ability of diagnostic testing and imaging to identify the presence or absence of a disease or condition. These studies compare the relative diagnostic strength of the test or device with a reference standard, therefore, guiding clinical decisions on the reliability of the test, the need for further tests, and whether to monitor or treat a particular condition. Inadequate and incomplete reporting of diagnostic accuracy studies can disguise methodological deficiencies and ultimately result in study bias and the inability to translate research findings into daily clinical practice. The Preferred Reporting Items for Diagnostic Accuracy Studies in Endodontics (PRIDASE) guidelines are being developed in order to improve the accuracy, transparency, completeness and reproducibility of diagnostic accuracy studies in the speciality of Endodontology. The aim of this paper is to report the process used to develop the PRIDASE guidelines based on a well-established consensus process. The project leaders (PD, VN) formed a steering committee of nine members (PD, VN, PA, AF, DR, SP, CK, MP, HD) to oversee and manage the project. The PRIDASE steering committee will develop the initial draft of the PRIDASE guidelines by adapting and modifying the Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015 guidelines, adding new items related specifically to the nature of Endodontics and incorporate the Clinical and Laboratory Images in Publication (CLIP) principles. The initial guidelines will consist of a series of domains and individual items and will be validated by the members of a PRIDASE Delphi Group (PDG) consisting of a minimum of 30 individuals who will evaluate independently the individual items based on two parameters: 'clarity' using a dichotomous scoring (yes/no) and 'suitability' for inclusion using a 9-point Likert Scale. The scores awarded by each member and any suggestions for improvement will be shared with the PDG to inform an iterative process that will result in a series of items that are clear and suitable for inclusion in the new PRIDASE guidelines. Once the PDG has completed its work, the steering committee will create a PRIDASE Meeting Group (PMG) of 20 individuals from around the world. Members of the PDG will be eligible to be the part of PMG. The draft guidelines and flowchart approved by the PDG will then be presented for further validation and agreement by the PMG. As a result of these discussions, the PRIDASE guidelines will be finalized and then disseminated to relevant stakeholders through publications and via the Preferred Reporting Items for study Designs in Endodontology (PRIDE) website (http://pride-endodonticguidelines.org). Periodic updates to the PRIDASE guidelines will be made based on feedback from stakeholders and end-users.

Correlation between the clinically diagnosed inflammatory process and periapical index scores in severely painful endodontically involved teeth

Aim

To assess and correlate three distinct states of severely painful endodontically derived inflammation with their depiction on periapical radiographs using periapical index (PAI) scores.

Methodology

During a period of 15 months, 368 consecutively enrolled patients with suspected endodontic emergency conditions were examined at the University of Zurich, Center of Dental Medicine. Cases with a severely painful (numeric rating scale, NRS‐11 > 6) endodontically involved tooth and a clear pulpal and apical diagnosis (n = 162) were selected (one tooth per patient). Teeth were divided into three groups according to the clinically diagnosed main location of the inflammatory process: level 1: pulp (positive response to cold test), level 2: periodontium (no response to cold without swelling) and level 3: periapical tissues (no response to cold with swelling). Periapical radiographs were obtained using a digital unit and analysed by two calibrated observers. For level 2, which had the highest PAI variance (n = 76), the PAI scores were further scrutinized regarding their dependence on tooth location and the duration of pain. Data were analysed using chi‐squared and non‐parametric tests, alpha = 0.05.

Results

Overall, the PAI scores correlated well with the clinically diagnosed main location of periapical inflammation (Spearman’s rho = 0.5131, P < 0.001), with level 1 having the lowest scores by far (P < 0.001) and level 2 having significantly lower scores compared to level 3 (P < 0.05). However, a PAI score of 5 was found in merely 3 teeth within the entire cohort, and 49% of the teeth in the level 2 group had no radiolucency (PAI < 3). Within level 2, the PAI scores were not dependent on tooth location but were substantially (P < 0.001) higher for teeth which had hurt for more than one week, and for root filled teeth.

Conclusions

For the analysed, severely painful endodontically involved teeth, the clinically diagnosed main location of inflammation was reflected by the periapical index. PAI scores were not significantly influenced by anatomical noise, yet in some cases under‐estimated the clinical situation.

Available chlorine consumption from NaOCl solutions passively placed in instrumented human root canals

AIM

To monitor chlorine consumption from nonagitated aqueous sodium hypochlorite (NaOCl) solutions in human root canals using a recently developed assay, which can determine the order of magnitude of available chlorine in small volumes of liquid.

METHODOLOGY

The root canals of 80 extracted single-rooted human teeth were instrumented to ProTaper Universal F4 and irrigated using 1% NaOCl. Subsequently, canals were irrigated with copious amounts of deionized water to rinse out the residual chlorine. Subsequently, the teeth were sealed externally and placed in a water bath of 37 °C. Root canals were filled with NaOCl of 1%, 2.75%, 5.5%, or distilled water for 1, 10, 100 or 1000 min (n = 5 teeth per solution and time). Consumption of chlorine was measured using paper points pre-impregnated with 15% potassium iodide. Colour change of the paper points was determined photo-electronically, assessing their red value after absorbing solutions from root canals. Measurements were compared to a standard series of NaOCl down to 0.001% (n = 5 paper points per concentration).

RESULTS

Red values of the paper points inserted into the root canal were affected by initial NaOCl concentration and time (two-way anova, P < 0.05). If NaOCl concentrations above 0.1% are considered to be clinically relevant, then 5.5% NaOCl retained its activity in the root canal for more than 100 min, whereas 1% NaOCl lost its activity between 10 and 100 min.

CONCLUSIONS

Nonagitated NaOCl solutions can remain biologically active in human root canals for extended time periods.