Postoperative assessment of fracture reduction and osteosynthesis materials using photon-counting detector CT in maxillofacial trauma – a pilot study

Abstract Purpose To assess postoperative fracture reduction and visualization of titanium-based and bioresorbable osteosynthesis materials in maxillofacial trauma surgery using ultra-high-resolution photon-counting detector computed tomography (PCD-CT) compared with cone-beam computed tomography (CBCT). Methods Fractures were induced in six cadaveric pig mandibles at the angle, body, and parasymphysis and were stabilized using various titanium and bioresorbable plate systems. Specimens were scanned with CBCT and dose-matched PCD-CT in the ultra-high resolution mode, applying standard and low-dose protocols. Two observers assessed fracture reduction and implant delineation using a 5-point visual analog scale. Fracture gap and osteosynthesis materials were quantitatively measured and compared to ground-truth values. Descriptive statistics and inter-reader agreement (weighted κ) were calculated. Results PCD-CT enabled excellent assessment of fracture reduction and visualization of osteosynthesis materials, with perfect inter-observer agreement (Median = 5, IQR, 5–5; κ = 1.0, p < 0.001), whereas low-dose CBCT showed reduced image quality and lower reproducibility (Median = 4, IQR, 4–4; κ = 0.92; p < 0.001). Bioresorbable plates were not directly visible using either scanner, but the associated screw drill holes were reliably delineated. PCD-CT achieved the smallest measurement deviations of fracture gap and osteosynthesis materials compared with ground truth, and with superior reproducibility (κ = 0.74–0.84; ICC = 0.95–0.99; all p < 0.001), outperforming CBCT across most parameters. Conclusions Ultra-high resolution PCD-CT combines superior visualization and precise measurements compared with CBCT even at low radiation dose. With further clinical validation, these findings highlight PCD-CT’s strong potential for perioperative imaging in maxillofacial trauma, particularly benefiting younger patients who require repeated scans.