{'fraction_non_alphanumeric': 0.023233301064859633, 'fraction_numerical': 0.000968054211035818, 'mean_word_length': 5.118343195266272, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
A Novel Finite Element Modeling Method for Periodontal Ligament of Impacted Maxillary Tooth

How to build a precise finite element model for periodontal ligament (PDL) of impacted tooth is a key step in numerical simulation of orthodontics. However, it is difficult to obtain accurate three-dimensional model of impacted tooth which embed in alveolar bone. In this paper, combined with reverse engineering and CT image, a new finite element method is introduced. Firstly, create the surface model of impacted tooth after separating it from CT image by using threshold. Secondly, filter the superfluous points in point cloud by programming. Then grid the point cloud, and smooth the curved surface to create the closed 3D entity model. Finally, the finite element model of impacted tooth and periodontal ligament (PDL) were built by finite element pre-processing. Compared with the traditional modeling method, the new approach is faster, more precise, which served as a more effective and practical means for orthodontics simulation.