Evaluation of maxillofacial traumatic injuries severity based on STL models.

Abstract

Purpose.To verify the possibility of using *.stl models for the assessment of maxillofacial traumatic injuries by FISS and MFISS severity scores in the remote mode of forensic evaluation. Methods. Quantitative assessment of maxillofacial traumas was made by facial injury severity score (FISS) and maxillofacial injury severity score (MFISS) among 27 patients who have undergone CBCT after road-traffic accidents. Initially, FISS and MFISS scores were estimated based on clinical examination, medical documentation, and obtained X-ray data-sets (FISS1 and MFISS1). *.dcm-files of patients were converted into *.stl-files via InVesalius software (CTI, Brazil) and sent to the forensic dental experts with all the needed descriptive information regarding clinical characteristics of maxillofacial traumas, but without access to original *.dcm files. In remote mode, experts estimated injury severity by FISS2 and MFISS2 scores. Results.Mean scores for maxillofacial traumatic injuries based on clinical examination, medical documentation, and obtained X-ray data-sets were following: 3.54±1.03 and 16.29±5.21 for FISS1 and MFISS1 respectively; while mean FISS2 and MFISS2 scores were 2.98±1.74 and 13.32±8.73, respectively. Statistical correspondence between FISS1 and FISS2 scores reached r=0.84 (р<0.05), while such correspondences between MFISS1 and MFISS2 scores reached 0.92 (р<0.05). Conclusions.Even though analysis of stl-files obtained from patients with maxillofacial traumatic injuries provoked underestimation of FISS and MFISS scores with an increase of standard errors deviations, such a digital approach also provides the possibility for quick assessment of preliminary trauma severity by a forensic dental expert in the remote mode of evaluation.