Photon-counting CT outperforms dental CBCT in detecting small accessory canals in root-filled teeth in a phantom...

Area of Science:

• Dentistry
• Medical Imaging
• Radiology

Background:

• Accurate visualization of dental structures in root-filled teeth is crucial for endodontic assessment.
• Root canal fillings can cause artifacts, challenging the detection of small accessory canals.

Purpose of the Study:

• To compare the efficacy of photon-counting-detector CT (PCD-CT) and cone-beam CT (CBCT) in detecting small accessory canals in the presence of root canal fillings.
• To evaluate imaging artifacts and measurement accuracy between PCD-CT and CBCT for endodontic applications.

Main Methods:

• A phantom model with bovine teeth containing root canal fillings and artificial accessory canals (200-1000 μm) was scanned using clinical PCD-CT (ultra-high-resolution) and dental CBCT (endodontic protocol).
• Canal visibility was assessed using signal-to-noise criteria, and diameters were compared against micro-CT measurements.
• Blooming artifacts from root canal fillings were quantified using full width at half maximum (FWHM).

Main Results:

• PCD-CT detected all accessory canals down to 400 μm and 81.5% at 200 μm.
• CBCT reliably detected canals ≥ 800 μm, with detection rates dropping significantly at smaller sizes (47.2% at 400 μm, 0% at 200 μm).
• PCD-CT demonstrated lower measurement errors for canal diameters, with similar artifact widths observed between modalities.

Conclusions:

• PCD-CT offers superior detectability and measurement fidelity for small accessory canals in root-filled teeth compared to dental CBCT.
• PCD-CT shows significant potential for improving post-treatment endodontic imaging and assessment.
• Further research may explore PCD-CT's clinical utility in complex endodontic cases.