How do we and how should we deal with uncertainty in endodontics?

In many clinical cases a dentist may feel certain when for example diagnosing, deciding on treatment, or assessing the prognosis-in other cases many dentists may feel a degree of doubt or uncertainty. This paper aims to explore the philosophical concept of uncertainty and its different dimensions, using the condition "persistent apical periodontitis associated with a previously root filled tooth" as an example. Acknowledging that uncertainty exists in any clinical situation can be perceived as uncomfortable, as some might regard it as a weakness. Whilst some types of uncertainty met in dental practice can be addressed and reduced, there are other types which are inevitable and must be accepted. To make sound decisions, it is pertinent that the dentist reflects on and values the consequences of uncertainty. In this paper, a conceptual model is presented by which the dentist can identify the type of uncertainty in a clinical case, making it possible to decide on a strategy on how to manage the uncertainty and its possible consequences, with the aim to support the dentist's care for their patients. The understanding that uncertainty exists and the ability to acknowledge and be comfortable with it when making decisions should be addressed throughout our professional career, and thus ought to be developed during undergraduate education. Some suggestions on how teachers could target this are given in the paper.

Conclusiveness resolves the conflict between quality of evidence and imprecision in GRADE.

OBJECTIVES: The objective of our article is to show how "quality of evidence" and "imprecision," as they are defined in Grading of Recommendations Assessment, Development, and Evaluation (GRADE) articles, may lead to confusion. We focus only on the context of systematic reviews. STUDY DESIGN AND SETTING: We analyze, with the aid of standard probabilistic and statistical concepts, the concepts of quality of evidence and imprecision as used in the GRADE framework. This enables us to point out some weaknesses in the relation between "quality of evidence" and "imprecision." RESULTS: The GRADE framework contains terms familiar from classical statistics, but these terms are used in nonstandard ways. Notably, "imprecision" does not have the meaning in the GRADE framework that it has in statistics, and the well-known table of "evidence levels" wrongly suggests that "quality of evidence" and "accuracy" express the same concept-they do not. CONCLUSION: We believe that "conclusiveness" rather than "imprecision" would be a suitable term to use when the question whether the CI excludes or includes certain critical margins is being addressed. Conclusiveness could also replace quality of evidence as the final step for a systematic reviewer.