Evaluation of Revitalization Success Using i-PRF in Non-Surgical Root Canal Retreatment

Official title

Evaluation of Revitalization Success Using i-PRF in Non-Surgical Root Canal Retreatment: A Clinical Study

Overview

The goal of this randomized controlled clinical trial is to determine whether regenerative endodontic treatment can improve healing outcomes in teeth with apical periodontitis following failed root canal treatment. The study includes adult patients who require non-surgical root canal retreatment due to persistent periapical lesions. The main questions it aims to answer are: Does regenerative endodontic treatment improve periapical healing compared with conventional non-surgical root canal retreatment? Does regenerative treatment increase long-term treatment success and tooth survival? Researchers will compare conventional non-surgical root canal retreatment with regenerative endodontic treatment using injectable platelet-rich fibrin (i-PRF) to see if the regenerative approach results in better clinical and radiographic outcomes. Participants will: Be randomly assigned to receive either conventional retreatment or regenerative endodontic treatment. Undergo clinical and radiographic evaluations over a two-year follow-up period. Be assessed for pain, sensitivity, pulp vitality, hard tissue formation, and periapical healing.

Detailed description

Apical periodontitis is a common consequence of failed root canal treatment and is primarily associated with persistent intraradicular infection. Although non-surgical root canal retreatment remains the standard treatment approach for failed primary endodontic therapy, reported failure rates range between 23% and 30%. Even after thorough chemomechanical preparation, complete elimination of microorganisms may not always be achieved. In addition, conventional treatment does not restore pulp vitality and may compromise the structural integrity of the remaining tooth tissue.

Regenerative endodontic procedures have emerged as a biologically based alternative aimed at promoting tissue regeneration within the root canal system. By utilizing biological scaffolds and growth factor-rich preparations, regenerative therapy may enhance healing, support revascularization, and potentially restore natural defense mechanisms of the tooth.

This study is designed as a randomized controlled clinical trial comparing conventional non-surgical root canal retreatment with regenerative endodontic treatment. The regenerative protocol incorporates injectable platelet-rich fibrin (i-PRF), an autologous blood-derived biomaterial obtained through low-speed centrifugation. i-PRF contains growth factors and bioactive components that may support angiogenesis, cell migration, and tissue repair.

Following local anesthesia and rubber dam isolation, previously obturated root canal fillings will be removed. Standardized chemomechanical preparation and irrigation protocols will be performed according to the assigned treatment group. In the regenerative group, i-PRF will be applied as a biological scaffold prior to placement of a bioceramic material to achieve coronal sealing. In the conventional retreatment group, canals will be obturated using established root canal filling techniques.

All procedures will be performed under standardized clinical conditions. Radiographic examinations will be obtained using positioning devices to ensure reproducibility and standardization of angulation. Patients will be monitored periodically over a two-year follow-up period to assess healing progression and treatment outcomes.

This study seeks to provide evidence regarding the biological and clinical potential of regenerative endodontic therapy as an alternative to conventional retreatment in teeth with persistent apical periodontitis.

Interventions

• Procedure Non-Surgical Root Canal Retreatment
  Conventional non-surgical root canal retreatment will be performed under local anesthesia and rubber dam isolation. Previous root canal filling materials will be removed, followed by standardized chemomechanical preparation and irrigation. The canals will be obturated using resin-based sealer and gutta-percha with lateral condensation technique, and the tooth will be restored with a permanent coronal restoration.
• Procedure Regenerative Endodontic Treatment
  Regenerative endodontic treatment will be performed under local anesthesia and rubber dam isolation. After removal of previous root canal filling materials and standardized canal preparation, injectable platelet-rich fibrin obtained from the patient's autologous blood will be applied into the canal space as a biological scaffold. Mineral trioxide aggregate will be placed coronally, followed by permanent composite restoration.

Primary outcome measures

• Change in Periapical Index (PAI) Score [Time frame: Baseline and up to 24 months]

Secondary outcome measures (4)

• Postoperative Pain Intensity [Time frame: Baseline and up to 24 months]
• Percussion and Palpation Sensitivity [Time frame: Baseline and up to 24 months]
• Pulp Vitality Response [Time frame: Baseline and up to 24 months]
• Proportion of Teeth With Successful Healing (PAI ≤ 2) [Time frame: Baseline and up to 24 months]

Eligibility criteria

Inclusion criteria

• Patients aged between 18 and 50 years.
• Single-rooted maxillary anterior teeth with closed apices.
• Presence of periapical lesion confirmed radiographically.
• Previously treated root canal tooth requiring non-surgical retreatment.
• Tooth has not previously undergone non-surgical root canal retreatment.
• Tooth is considered restorable.
• Patient is systemically healthy.
• Patient is willing to participate and provides informed consent.

Exclusion criteria

• Teeth without radiographic evidence of periapical lesion.
• Teeth with developmental anomalies.
• Patients with systemic diseases that may affect healing.
• Pregnant patients.
• Teeth presenting with internal or external root resorption.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Treatment

Study locations

Turkey (Türkiye) · 1 center

• Marmara University — Istanbul

Identifiers

NCT: NCT07448571 · 2025-KAEK-43

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗