Radiation-specific Automated Dosimetric dental, Mandible, and maxilla Annotation for Predicting Periodontal Problems (RADMAP): A semi-automated clinical tool for enhanced cross-disciplinary dosimetric oral risk communication and osteoradionecrosis assessment

Purpose/Objective(s)Osteoradionecrosis of the jaw (ORN) is a severe complication of head and neck cancer (HNC) radiotherapy (RT), significantly impacting patient quality of life. Current dose assessment relies on whole-mandible dosimetry, limiting personalized, tooth-specific region risk evaluation. The lack of standardized methods to document and analyze dose distributions to tooth-bearing regions further hampers dental and maxillofacial decision-making. This study develops and evaluates RADMAP, a (semi-)automated tool for segmenting tooth-based jaw regions, enabling patient- and tooth-specific radiation dose mapping to improve dental dose reporting and ORN risk assessment. Methods and MaterialsA total of 736 tooth locations from 23 HNC patients treated with definitive RT were analyzed, including 11 who developed ORN. The RADMAP tool applies an angular ray-based algorithm to automatically segment the mandible and maxilla into 32 tooth-specific jaw regions, with optional manual refinement (semi-automated), outputting radiation dose mapping in both tabular and odontogram formats. Mean dose values from manually contoured tooth roots were compared with RADMAP-segmented alveolar regions (fully and semi-automated). Interobserver agreement among six users was evaluated. Whole-mandible, manual tooth, and tooth-based jaw segment (alveolar and basal) doses were compared between regions with and without ORN development. ResultsMean dose correlation between RADMAP-segmented alveolar jaw regions and manually segmented tooth roots was high for both fully and semi-automated approaches (R{superscript 2} = 0.98, p<0.0001), demonstrating accurate dose estimation. Interobserver agreement showed 95% limits of {+/-}2.9 Gy for mandibular alveolar segments, confirming reproducibility. Tooth-based jaw segments showed a significant differentiation in radiation dose for the ORN-positive versus ORN-negative sites (difference in mean dose (DIM): 12.4 {+/-}3.7 Gy, p=0.0008), which was not seen when considering the whole-mandible dose (DIM=6.2 {+/-}4.3 Gy, p=0.17), demonstrating RADMAPs promise for improved ORN risk assessment. ConclusionRADMAP enables accurate, tooth-specific dose mapping of the mandible and maxilla, and potential improved ORN risk differentiation beyond whole-mandible dosimetry. Tooth-based dose reporting can personalize treatment, enhance multidisciplinary communication, and support prevention of radiation-related orodental sequelae.