PURPOSE: To compare cone-beam computed tomography (CBCT) with photon-counting detector computed tomography (PCD-CT) at equivalent radiation doses, focusing on qualitative and quantitative parameters relevant to dental implant surgery. METHODS: This ex vivo comparative study of porcine specimens assessed five imaging protocols with both CBCT and PCD-CT at three effective radiation dose levels (high: 360µSv, standard: 145µSv, low: 20µSv) to evaluate image quality, artifact burden, metal artifact susceptibility, and quantitative bone measurements in the mandibular region. Three blinded readers analyzed the data using a 5-point Likert scale (5 = highest to 1 = lowest rating) and performed linear bone measurements at implant planning sites. Statistical analysis included descriptive statistics and inter-reader reliability assessment using intraclass correlation coefficients (ICC). RESULTS: Each reader evaluated 30 data sets (12 CBCT, 18 PCD-CT), with 24 implant planning sites per imaging protocol. High-dose PCD-CT demonstrated the best image quality and diagnostic interpretability (4.89 ± 0.27), followed by standard-dose PCD-CT and CBCT (4.50 ± 0.73
4.33 ± 0.61), with low-dose protocols showing intermediate quality with higher artifact burden. In comparison to CBCT, PCD-CT demonstrated superior performance in reducing implant-induced artifacts across all protocols. Quantitative bone measurements showed minimal variability, meeting clinical precision requirements for computer-assisted implant surgery. Both qualitative (ICCs:0.70-0.89
p <
0.001) and quantitative (ICCs:0.79-1
p <
0.001) analyses demonstrated high reliability, regardless of the reader's experience. CONCLUSIONS: PCD-CT demonstrated superior image quality and reduced artifacts compared with CBCT at all radiation dose levels. These findings highlight PCD-CT's potential to enhance implant planning and improve clinical outcomes with reduced radiation exposure while maintaining diagnostic accuracy.