Radiotherapy-induced alterations in trabecular microarchitecture and bone mass of the mandibular condylar process: A
Luiz Felipe Palma1, Rafael Verardi Serrano2, Luana Campos3
1Department of Pathology, Federal University of São Paulo, São Paulo, SP, Brazil.
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 115 ± 35.4 before radiotherapy and 104 ± 34.0 after radiotherapy. The mean fractal dimension values before and after radiotherapy were 1.30 ± 0.110 and 1.23 ± 0.129, 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.
