AI-Based Working Length Determination in Curved Root Canals (AI-CURL)

August 21, 2026 updated by: Hatice BÜYÜKÖZER ÖZKAN, Alanya Alaaddin Keykubat University

Evaluation of the Effectiveness of Artificial Intelligence in Determining the Accurate Working Length of Curved Root Canals in Endodontic Treatment

This study tests whether artificial intelligence (AI) can accurately measure the length of curved root canals from dental x-rays. Curved root canals are hard to measure correctly, and wrong measurements can lower the success of root canal treatment.

Adults over 18 years old who need root canal treatment can take part. Researchers will use x-rays taken during the patient's normal treatment. No extra x-rays, procedures, or visits are needed. An AI program will be trained to measure canal length automatically, and its measurements will be compared to measurements made by a human expert.

The results may show whether AI can measure root canal length faster and more consistently, which could help dentists plan treatment more accurately in the future.

Study Overview

Status

Not yet recruiting

Detailed Description

Working length determination is a critical step in root canal treatment, and inaccurate measurement can lead to under- or over-instrumentation, post-operative pain, and reduced treatment success. This is particularly challenging in curved root canals, where the apical foramen often deviates from the anatomical or radiographic apex, and where small endodontic files are difficult to visualize on periapical radiographs. Conventional methods for working length determination, including tactile sensation, electronic apex locators, and radiographic interpretation, are subject to observer variability and technical limitations, especially as canal curvature increases.

Recent advances in artificial intelligence, particularly deep learning-based image analysis, have shown promise in improving the objectivity and consistency of measurements derived from dental radiographs. This study aims to develop and evaluate deep learning models (including convolutional neural network architectures such as GoogleNet Inception V3, U-Net, Mask R-CNN, and YOLO-based networks) for the automatic detection and measurement of curved root canal length on periapical radiographs, and to compare the performance of these models with measurements made by a human observer.

Periapical radiographs will be obtained using the paralleling technique during the working length confirmation stage of routine root canal treatment, as part of the patient's standard clinical care. No additional radiographic exposure, procedure, or clinical visit will be performed solely for research purposes. Radiographic images will be anonymized and labeled using canal length segmentation, with pixel-based measurements calibrated to millimeters based on DICOM metadata.

The dataset will be divided into training, validation, and test subsets. Model performance will be evaluated using standard classification and segmentation metrics, including sensitivity, precision, F1 score, Intersection over Union (IoU), and Receiver Operating Characteristic (ROC) curve analysis with area under the curve (AUC).

Study Type

Observational

Enrollment (Estimated)

200

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

The study population consists of adult patients (18 years and older) presenting for routine root canal treatment at the Department of Endodontics, Alanya Alaaddin Keykubat University Faculty of Dentistry, who have radiographically identified curved root canals. No sex-based restriction is applied. Periapical radiographs obtained during the working length confirmation stage of standard clinical care will be used; no additional radiographic exposure or procedure will be performed for research purposes.

Description

Inclusion Criteria:

  • Eligibility Criteria
  • Age 18 years or older
  • Presenting for routine root canal treatment at Alanya Alaaddin Keykubat University Faculty of Dentistry
  • Radiographically identified curved root canal(s)
  • Periapical radiograph obtained using the paralleling technique during working length confirmation
  • Willing and able to provide informed consent

Exclusion Criteria:

  • Age under 18 years
  • Root canals without curvature
  • Periapical radiographs of insufficient diagnostic quality (e.g., distortion, poor image quality preventing accurate canal length assessment)
  • Unwillingness to provide informed consent

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Sensitivity of AI Model in Detecting Curved Root Canal Length
Time Frame: Measured once, at the time of model testing following completion of radiograph collection (estimated 12 months from study initiation)
Agreement between the AI-predicted root canal length and the length determined by a human observer on periapical radiographs, assessed by sensitivity, calculated as TP/(TP+FN), where TP (true positive) represents the overlapping region between the ground truth and predicted segmentation, and FN (false negative) represents the region present in the ground truth but not in the prediction.
Measured once, at the time of model testing following completion of radiograph collection (estimated 12 months from study initiation)
Precision of AI Model in Detecting Curved Root Canal Length
Time Frame: Measured once, at the time of model testing following completion of radiograph collection (estimated 12 months from study initiation)
Agreement between the AI-predicted root canal length and the length determined by a human observer on periapical radiographs, assessed by precision, calculated as TP/(TP+FP), where FP (false positive) represents the region present in the prediction but not in the ground truth.
Measured once, at the time of model testing following completion of radiograph collection (estimated 12 months from study initiation)
F1 Score of AI Model in Detecting Curved Root Canal Length
Time Frame: Measured once, at the time of model testing following completion of radiograph collection (estimated 12 months from study initiation)
F1 score of the AI-predicted root canal segmentation compared to ground truth on periapical radiographs, calculated as 2TP/(2TP+FP+FN), representing the harmonic mean of precision and sensitivity and interpreting the overlap between the ground truth and predicted pixels.
Measured once, at the time of model testing following completion of radiograph collection (estimated 12 months from study initiation)
Intersection over Union (IoU) of AI Model in Detecting Curved Root Canal Length
Time Frame: Measured once, at the time of model testing following completion of radiograph collection (estimated 12 months from study initiation)
Intersection over Union between the AI-predicted root canal segmentation and the ground truth segmentation on periapical radiographs, calculated as TP/(TP+FN+FP), representing the overlapping area between the predicted result and the ground truth segmentation area.
Measured once, at the time of model testing following completion of radiograph collection (estimated 12 months from study initiation)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Hatice Büyüközer Özkan, Associate Professor (Doç. Dr.), Alanya Alaaddin Keykubat University, Faculty of Dentistry

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

September 22, 2026

Primary Completion (Estimated)

November 22, 2026

Study Completion (Estimated)

December 22, 2026

Study Registration Dates

First Submitted

August 18, 2026

First Submitted That Met QC Criteria

August 21, 2026

First Posted (Actual)

August 26, 2026

Study Record Updates

Last Update Posted (Actual)

August 26, 2026

Last Update Submitted That Met QC Criteria

August 21, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data (periapical radiographs and associated measurements) contain identifiable patient imaging information. No data-sharing infrastructure or protocol has been established for this study, and sharing was not addressed in the informed consent obtained from participants. Data may be made available upon reasonable request to the corresponding author, subject to institutional and ethics committee approval.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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