K04.5
Conditions
Interventions
Group 1: This prospective observational study includes adult patients with persistent apical periodontitis undergoing endodontic retreatment as part of routine clinical care.
During standard treatment
Sponsors
Zentrum für Zahn-, Mund- und Kieferheilkunde Poliklinik für Zahnerhaltung und Parodontologie Universitätsklinikum Köln
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Inclusion criteria
Inclusion criteria: Age = 18 years and ability to provide informed consent. Presence of clinical symptoms such as pain, swelling, recurrent infections, purulent discharge, or tooth mobility. Evidence of an inadequate previous root canal treatment performed more than 6 months prior (e.g. incomplete root canal filling or missed root canals). Radiographically detectable periapical lesion associated with a previously root canal–treated tooth. The affected tooth is considered restorable based on clinical and restorative assessment. Written informed consent obtained prior to participation.
Exclusion criteria
Exclusion criteria: Non-restorable teeth, for example due to vertical root fractures, severe marginal attachment loss, severely obliterated root canals, or the presence of fractured instruments. Age < 18 years or inability to provide informed consent. Severely curved roots or anatomical conditions that substantially impede standardized endodontic retreatment. Compromised endodontic retreatment due to severely obliterated root canals or fractured instruments within the root canal system. Endodontic retreatment of mandibular premolars and mandibular anterior teeth.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| WHAT: Composition and diversity of the endodontic microbiome (intracanal and periapical). WHEN: At predefined time points during endodontic retreatment: T0 (Baseline): Before any mechanical or chemical disinfection, after access cavity preparation. T1: After mechanical and chemical instrumentation of the root canal T2: Two weeks after placement of the intracanal medicament / immediately before obturation. HOW: Analysis of microbial composition and diversity (e.g., Shannon index, relative abundances) using 16S rRNA gene sequencing of root canal samples. | — |
Secondary
| Measure | Time frame |
|---|---|
| Comparison of microbial composition between the root canal, apical region, subgingival crevicular fluid and saliva, as well as analysis of temporal changes in these oral microbial profiles. In addition, potential associations between oral microbial parameters and systemic inflammatory markers measured in blood are investigated. | — |
Countries
Germany
Contacts
Public ContactGreta Barbe
Zentrum für Zahn-, Mund- und Kieferheilkunde Poliklinik für Zahnerhaltung und Parodontologie Universitätsklinikum Köln
Outcome results
None listed