Purpose: Patients with head and neck cancer (HNC) who undergo dental procedures during radiotherapy (RT) face an increased risk of developing osteoradionecrosis (ORN). Accordingly, new tools must be developed to extract critical information regarding the dose delivered to the teeth and mandible. This article proposes a novel approach for visualizing 3-dimensional planned dose distributions on panoramic reconstruction computed tomography (pCT) images. Materials and Methods: Four patients with HNC who underwent volumetric modulated arc therapy were included. One patient experienced ORN and required the extraction of teeth after RT. In the study approach, the dental arch curve (DAC) was defined using an open-source platform. Subsequently, pCT images and dose distributions were generated based on the new coordinate system. All teeth and mandibles were delineated on both the original CT and pCT images. To evaluate the consistency of dose metrics, the Mann-Whitney U test and Student t-test were employed. Results: A total of 61 teeth and 4 mandibles were evaluated. The correlation coefficient between the 2 methods was 0.999, and no statistically significant difference was observed (P>0.05). This method facilitated a straightforward and intuitive understanding of the delivered dose. In 1 patient, ORN corresponded to the region of the root and the gum receiving a high dosage (approximately 70 Gy). Conclusion The proposed method particularly benefits dentists involved in the management of patients with HNC. It enables the visualization of a 3-dimensional dose distribution in the teeth and mandible on pCT, enhancing the understanding of the dose delivered during RT.

Purpose: The purpose of this study is to evaluate hangeshashinto rinse for oral discomfort in terminally-ill cancer patients and to compare the effectiveness of hangeshashinto rinse with or without honey rinse. Methods: Patients with oral discomfort were randomized to receive either hangeshashinto rinse or hangeshashinto with honey rinse as first-line treatment. Patients performed oral rinse three to five times a day for 2 weeks. Further, oral wetness, halitosis, oral mucositis, mouth discomfort, compliance of rinse were then evaluated before and after the intervention. Results: 144 patients were enrolled during this period and 22 patients completed the study (hangeshashinto 13 / hangeshashinto with honey 9). After the intervention, oral wetness was improved, and end-tidal concentration of hydrogen sulfide was decreased in both cases. Although there was no statistically significant difference, oral discomfort by subjective and objective evaluations, also and symptom of oral mucositis were improved. Other volatile sulfur compounds decreased. Frequency of rinsing between groups receiving hangeshashinto or hangeshashinto with honey did not differ, however, the acceptability was slightly better in the honey combination group. Conclusion: Both hangeshashinto rinse and hangeshashinto with honey rinse reduced end-tidal concentration of hydrogen sulfide and improved oral wetness. Oral rinse by hangeshashinto or hangeshashinto with honey may be effective for oral discomfort in terminally-ill cancer patients.