Model analysis of palatal rugae morphology before and after orthodontic treatment in forensic identification / 中国法医学杂志

ABSTRACT

Objective To evaluate the palatal rugae individual-specific properties and stability before and after orthodontic treatments for investigating the reliability of palatal rugae for individual identification of forensic dentistry based on the palatal rugae model ananlysis. Methods Maxillary models of 70 patients were obtained before and after orthodontic treatments respectively. Palatal rugae morphologic changes and individual identification were examined by model analysis including changes in number, orientation, shape, and length of palatal rugae, as well as mesial and distal endpoint displacement in the anterioposterior(AP) and mesiodistal (MD) direction. Furthermore, The examination of palatal rugae average match accuracy(%) was performed between the pre-treatment and post-treatment orthodontics models and post-treatment and duplicated post-treatment orthodontics models. Results ① The palatal rugae morphological changes were found and the incidence of palatal rugae changes were showed in length(28.6%), segmenta-tion(4.3%); unification(2.9%); orientation(1.4%) and shape(1.4%) after orthodontic treatment. Also the displacement of the distal endpoint of palatal rugae was 45.7% for anterioposterior indirection, 40% for mesiodistal indirection after orthodontic treatment, while the anterioposterior displacement of the mesial endpoint of palatal rugae was 32.9% and mesiodistal displacement was 17.1%. ② The identical palatal rugae patterns were not found both the pre-treatment and post-treatment groups. ③ The palatal rugae average match accuracy was 92.19% between pre-treatment and post-treatment groups, however, the rate had increased by 99.05% when matching the palatal rugae patterns of post-treatment groups to their duplicates. Conclusion Palatal rugae patterns have the high specific properties to each indivi-dual. Although there are some changes in morphology of palatal rugae after orthodontic treatment, it still can be used as a novel method for individual identification in forensic dentistry.