Radiotherapy-induced alterations in trabecular microarchitecture and bone mass of the mandibular condylar process: A retrospective analysis using fractal dimension and pixel intensity on digital panoramic radiographs

Purpose: To evaluate the impact of conventional 3-dimensional (3D) conformal radiotherapy on the mandibular condylar process in patients with head and neck cancer using pixel intensity and fractal dimension analyses of digital panoramic radiographs.Materials and Methods: Pre-and post-radiotherapy radiographs from 32 patients were digitally analyzed by a single experienced researcher.Regions of interest were selected in the right mandibular condylar process, specifically at the most constricted area corresponding to the condylar neck.Pixel intensity and fractal dimension analyses were subsequently performed.Results: Comparison between the evaluation periods demonstrated a statistically significant decrease in both mean pixel intensity and fractal dimension after radiotherapy.The mean pixel intensity was 11535.4before radiotherapy and 10434.0after radiotherapy.The mean fractal dimension values before and after radiotherapy were 1.300.110and 1.230.129,respectively.Conclusion: Conventional 3D conformal radiotherapy appears to lead to deleterious changes in the microarchitecture and bone mass of the mandibular condylar process in patients with head and neck cancer.Further studies are warranted to determine whether patients with radiation-induced low bone quality are more susceptible to complications such as mandibular fractures and temporomandibular joint dysfunction.(Imaging Sci Dent 20250314)