OBJECTIVE: The European Society of Endodontology (ESE) is in the process of developing S3-level clinical practice guidelines for the treatment of pulpal and apical disease. In order to support robust systematic literature reviews, appropriate outcome measures (OMs) with minimum follow-up times must first be identified. Hence, the current project aimed to identify the appropriate OMs with minimum/maximum follow-up time to assess the effectiveness of endodontic treatment for pulpitis and apical periodontitis for use in the development of ESE S3-level guidelines through a standard consensus-based methodology.
METHODS: After a literature search, lists of relevant OMs were identified by the guideline development group (GDG) for the treatment of pulpitis (working group [WG] 1), the non-surgical treatment of apical periodontitis (WG 2), the surgical treatment of apical periodontitis (WG 3) and the regenerative treatment of apical periodontitis (WG 4). OMs relevant to each WG were ranked by the 43 members of the GDG in their importance to the patient using a 9-point Likert scale. Items with a score of 7-9 (critical importance) by more than 70% and items with a score of 1-3 (limited importance) by less than 30% of members were included, whereas the items with a score of 1-3 by more than 70% and items with a score of 7-9 by less than 30% were excluded. Several online Delphi meetings established an edited list of only important OMs. The ranked OMs were discussed by the GDG and harmonized to produce \'most critical\', \'critical\' and \'important\' measures. After establishing the final ranked measures, the minimum and maximum length of follow-up related to each OM was defined by the guideline steering group.
RESULTS: The Delphi survey took place over two rounds. The patient-reported outcome measure (PROM) \'tooth survival\' was rated the \'most critical measure\' in all four WGs, while other PROMs including \'pain\' and \'need for medication\' were considered \'critical\', alongside the clinician-reported outcome measures (CROM), \'radiographic assessment\'. The PROMs \'The need for further intervention\' and \'oral-health-related-quality-of-life\' (OHRQoL) were included, but as \'important\' not \'critical\' measures. Differences occurred between WGs with \'vitality testing\' defined as critical in WG1 and \'increased length and width of the root\' defined as \'critical\' in WG4. A minimum of 1-year and maximum of \'as long as possible\' for all OMs were deemed necessary, except \'pain\', \'swelling\', \'medication\' and \'OHRQoL\', where shorter follow-up was accepted.
CONCLUSIONS: The GDG consensus process established the PROM \"tooth survival\" as the \"most-critical\". The identified OMs and length of follow-up will be applied to all the commissioned systematic reviews that will inform the subsequent process when developing the ESE S3-level clinical practice guidelines.

The European Society of Endodontology (ESE) is in the process of developing S3Level Clinical Practice Guidelines for the treatment of pulpal and apical disease for the benefit of clinicians and patients. In order to ensure a homogenous review process in the development of the clinical practice guidelines, it is essential that the core outcomes for all endodontic treatments are standardized and recommendations are made regarding minimum follow-up time specific to each outcome measure. In the absence of a recognized core outcome set in Endodontics, the current project aimed to follow an established consensus process to define the most appropriate clinician and patient-reported outcomes. As part of the project, recommendations will also be agreed regarding an acceptable minimum follow-up period for studies by literature review and group discussion. The selected outcome measures and follow-up periods will be used in subsequent systematic analyses of the literature to investigate the effectiveness of endodontic treatment to alleviate pulpitis and apical periodontitis. In this paper, previous reviews, ESE Guidelines and Position Statements were searched in order to compile a list of potentially important outcome measures for the treatment of pulpitis (working group 1), the nonsurgical treatment of apical periodontitis (working group 2), the surgical treatment of apical periodontitis (working group 3) and the regenerative treatment of apical periodontitis (working group 4). Initially, the two S3 guideline leads selected two independent senior clinical academics with experience of evidence-based dentistry to lead each of the four working groups forming a 10-member steering group. The working group leads in turn selected 32 academics with experience of evidence-based dentistry to lead the individual systematic reviews contained within the respective working groups. These 42 individuals make up the Guideline Development Group (GDG). Prior to the selected systematic reviewers commencing writing and submitting the review protocol, the complete list of outcome variables identified in this document will be ranked by the 42 members of the GDG in their importance to the individual patient using a 9-point Likert scale. A summary of the survey scores will thereafter be shared with the members of the group and the final list of clinician and patient-reported outcome measures rated as critical for decision making (7-9 on Likert scale by majority of survey participants) to guide systematic reviews will be consented and confirmed during an online meeting of the steering group. In this online meeting, another aspect with regard to meaningfulness of clinical trial results to be addressed in systematic reviews will be consented: length of follow-up. In order to develop high quality guidelines, it is suggested that the follow-up period after treatment should be related to the specific outcome measure being addressed; however, a minimum of one year for assessing the effectiveness of treatments for pulpitis and apical periodontitis should be considered. It is accepted, that selected research questions that focus on pain, swelling, medication taken or investigating diagnostic accuracy are likely to have shorter follow-up periods. As a result of the GDG consensus process, the outcome measures and length of follow-up will, alongside the use of standard instruments to assess the methodological quality of clinical trials and other comparative studies, be applied to all the commissioned systematic reviews that will inform the subsequent process when developing the ESE S3 Level Clinical Practice Guidelines.

The primary objective of this systematic review was to compare treatment outcomes of direct and indirect permanent restorations in endodontically treated teeth, and provide clinical suggestions for restoring teeth after endodontic treatment.
Electronic databases (Medline, EMBASE, CENTRAL) and gray literature were screened for articles in English that reported on prospective and retrospective clinical studies of direct or indirect restorations after endodontic treatment with an observation period of at least 3 years. Primary outcomes were determined to be short-term (≤ 5 years) and medium-term (> 5 and ≤ 10 years) survival. Secondary outcomes included restorative and endodontic success of restored teeth. The quality of included studies and risk of bias were assessed using Cochrane Collaboration\'s tool for RCTs (randomized controlled trials), the Newcastle-Ottawa Scale for cohort studies, and the Agency for Healthcare Research and Quality (AHRQ) methodology checklist for cross-sectional studies. The GRADE system was used for assessing collective strength of the overall body of evidence.
Of 2547 screened articles, only 9 (2 RCTs, 3 retrospective cohort studies, 3 cross-sectional studies) met the inclusion criteria, and 8 studies were used in the meta-analysis. In general, indirect restorations (mostly full crowns) showed higher 5-year survival (OR 0.28, 95% CI 0.19-0.43, p < 0.00001) and 10-year survival (OR 0.20, 95% CI 0.12-0.31, p < 0.00001) than direct restorations. However, there was no statistical difference in short-term (≤ 5-years) restorative success (OR 0.32, 95% CI 0.05-2.12, p = 0.24) and endodontic success (OR 0.88, 95% CI 0.72-1.08, p = 0.22).
Based on current evidence, there is a weak recommendation for indirect restorations to restore endodontically treated teeth, especially for teeth with extensive coronal damage. Indirect restorations using mostly crowns have higher short-term (5-year) and medium-term (10-year) survival than do direct restorations using composite or amalgam (GRADE quality of evidence: low to moderate), but no difference in short-term (≤ 5 years) restorative success (low quality) and endodontic success (very low quality). There is a need for high-quality clinical trials, especially well-designed RCTs.