Evidence map›Paper›PMID 42026978›Full record

SynthesisInternational endodontic journal2026

Factors Associated With Endodontic Flare-Ups: A Systematic Review and Meta-Analysis.

Jun Ohshima, Masayoshi Morita, Yuzo Kawanishi, Shotaro Abe, Nobutake Tanaka, Tsuyoshi Shimaoka, Hazuki Maezono, Yoshifumi Kinomoto, Mikako Hayashi

Abstract readSystematic ReviewMeta-Analysis
In one paragraph

Synthesis in International endodontic journal, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Jun OhshimaDepartment of Restorative Dentistry and Endodontology, Graduate School of Dentistry, the University of Osaka, Suita, Osaka, Japan.ORCID 0009-0006-3197-3069
Masayoshi MoritaDepartment of Restorative Dentistry and Endodontology, Graduate School of Dentistry, the University of Osaka, Suita, Osaka, Japan.ORCID 0009-0007-4890-3099
Yuzo KawanishiDepartment of Restorative Dentistry and Endodontology, Graduate School of Dentistry, the University of Osaka, Suita, Osaka, Japan.
Shotaro AbeDepartment of Restorative Dentistry and Endodontology, Graduate School of Dentistry, the University of Osaka, Suita, Osaka, Japan.ORCID 0009-0000-4153-2845
Nobutake TanakaDepartment of Restorative Dentistry and Endodontology, Graduate School of Dentistry, the University of Osaka, Suita, Osaka, Japan.
Tsuyoshi ShimaokaDepartment of Endodontics, Graduate School of Dentistry, Osaka Dental University, Hirakata, Osaka, Japan.ORCID 0009-0006-9625-1921
Hazuki MaezonoDepartment of Restorative Dentistry and Endodontology, Graduate School of Dentistry, the University of Osaka, Suita, Osaka, Japan.ORCID 0000-0002-1929-2045
Yoshifumi KinomotoDepartment of Restorative Dentistry and Endodontology, Graduate School of Dentistry, the University of Osaka, Suita, Osaka, Japan.
Mikako HayashiDepartment of Restorative Dentistry and Endodontology, Graduate School of Dentistry, the University of Osaka, Suita, Osaka, Japan.ORCID 0000-0002-3375-9027

Funding

Japan Society for the Promotion of Science 22K09980Japan Society for the Promotion of Science 22KJ2187Japan Society for the Promotion of Science 24K02620Japan Society for the Promotion of Science 24K19878Japan Society for the Promotion of Science 24K22184Japan Society for the Promotion of Science 25K13003Japan Society for the Promotion of Science 26K20175Japan Society for the Promotion of Science 26K20197Japan Society for the Promotion of Science 26K20198
6 · The paper itself

Abstract

backgroundEndodontic flare-ups, characterized by severe postoperative pain and/or swelling requiring unscheduled intervention, remain a clinically significant concern in root canal therapy. Identifying the factors associated with flare-ups is important for anticipating and managing patient outcomes.

objectivesThis systematic review and meta-analysis aimed to identify and synthesize clinical risk factors associated with endodontic flare-ups following root canal treatment.

methodsA comprehensive literature search was conducted in PubMed, Web of Science, and Scopus from database inception to September 2025. Eligible studies included observational or interventional studies evaluating the association between potential risk factors and flare-up occurrence. Risk of bias was assessed using ROBINS-I for non-randomized studies and the Cochrane RoB 2 tool for randomized controlled trials. Certainty of evidence was evaluated using the GRADE approach.

resultsA total of 15 eligible studies involving 24 320 cases met the inclusion criteria. The overall incidence of severe flare-ups was 2.83%. Significant risk factors included female sex, mandibular tooth location, non-vital pulp status, preoperative spontaneous pain, periapical lesions, multiple-visit treatment, re-treatment, and preoperative percussion pain. Among these, preoperative spontaneous pain (relative risk = 5.83) and percussion pain (relative risk = 3.45) demonstrated the strongest associations. By contrast, age, tooth type, number of root canals, instrumentation technique, and preoperative analgesic use were not significantly associated with flare-up incidence.

conclusionSeveral clinical factors appear to be associated with an increased risk of endodontic flare-ups. Although the overall certainty of evidence is low, these findings may assist clinicians in identifying higher-risk cases and counselling patients regarding potential postoperative outcomes. Further well-designed prospective studies are needed to strengthen the evidence base. TRAIL REGISTRATION: PROSPERO Systematic review registration number: CRD420251025451.

Indexed as

Postoperative PainRoot Canal TherapySymptom Flare UpHumansRisk Factorsendodonticspain managementpain measurementperiapical periodontitispostoperative complicationspostoperative paintreatment outcome

Identifiers

PMID42026978
PMCPMC13462396

What OpenQuestion holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.