The Present Study Aims to Follow up on All Root Canal Treatments Performed During the Year 2023 Within the Public Dental Services of the Counties of Jönköping, Kalmar, and Östergötland, Sweden. The Study is Entirely Observational in Nature.

NCT07244250 | Not Yet Recruiting DMC

• 1 other identifier: 2025-04871-02
• Study Type: observational
• Target: 1,500
• Locations: 0 countries
• Sites: N/A

Brief Summary

Each year, nearly 200,000 teeth undergo root canal treatment in Sweden, most of them within general dental care. However, studies that evaluate the outcomes of root canal treatments have almost exclusively been conducted at specialist or university clinics, where treatment conditions differ from everyday practice in general dentistry. Moreover, the design of such studies often limits the ability to generalize their findings to routine clinical settings. These earlier studies suggest that root canal treatment is a predictable procedure-about 80-90% of treated teeth become free from infection, 90% of patients experience no pain, and approximately 90% of root-filled teeth remain in the mouth six years after treatment. Still, the results from these studies cannot easily be applied to general dental care. This has been confirmed by large-scale epidemiological studies using X-rays to assess the technical quality of performed root fillings and to detect signs of disease. These studies have shown that many root fillings exhibit technical shortcomings, and a significant proportion of root-treated teeth have persistent infections. The current study aims to increase understanding of the factors that may explain why the results of root canal treatment in general dental practice appear to differ from those in specialist care. Based on epidemiological data, it is estimated that about 35% of teeth treated with root canal therapy in general dental practice still show signs of disease after treatment. What happens to these patients is largely unknown. Evidence suggests that teeth with persistent apical periodontitis rarely cause discomfort, and the condition often goes unnoticed. In the first part of the study, only patients who have already received treatment will be invited to participate, making this a retrospective study. Because it takes several years to evaluate the outcome of a root canal treatment, all patients aged 20 years and older who had a tooth root-filled in 2023 within the Public Dental Services of Jönköping, Kalmar, or Östergötland counties will be offered a free clinical and radiological examination-thus a three-year follow-up. The examination is entirely painless. In the second part of the study, patients with a root-filled tooth showing persistent disease will be offered a five-year follow-up (2026-2031). They will be grouped according to whether they choose to have further treatment or leave the condition untreated. This second phase will therefore constitute a prospective follow-up.

Conditions

Endodontic Treatment; Apical Periodontitis; Quality

Keywords

Root canal treatment; Apical periodontitis; Root filling

Outcome Measures

Primary Outcomes (2)

• Posttreatment frequency of apical periodontitis

  Apical periodontitis as defined as a periapcal radiolucency on an intra oral radiograph

  three year follow-up

• Posttreatment frequency of apical periodontitis

  Apical periodontitis as defined as a periapical radiolucency

  From completion of treatment to three year follow-up

Study Arms (1)

Patients

Patients who have received root canal treatment in the Public Dental Service in the counties of Jönköping, Kalmar and Östergötland

Eligibility Criteria

• Age: 20 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

All patients who have received and completed a root canal treatment in the Public Dental Service in the counties of Jönköping, Kalmar and Östergötland in 2023.

You may qualify if:

• All patients who have received and completed a root canal treatment in the Public Dental Service in the counties of Jönköping, Kalmar and Östergötland in 2023.

You may not qualify if:

• All patients who decline participation

Sponsors & Collaborators

• Region Jönköping County: lead
• Region Östergötland: collaborator
• Kalmar County Council: collaborator

MeSH Terms

Conditions

Periapical Periodontitis

Condition Hierarchy (Ancestors)

Periapical Diseases; Jaw Diseases; Stomatognathic Diseases; Periodontal Diseases; Mouth Diseases; Periodontitis

Central Study Contacts

Fredrik Frisk, PhD

CONTACT

46739811389; Fredrik.Frisk@rjl.se

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: OTHER
• Target Duration: 8 Years
• Sponsor Type: OTHER GOV
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 17, 2025
• First Posted: November 24, 2025
• Study Start: March 1, 2026
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2027
• Last Updated: December 16, 2025

Record last verified: 2025-10