Method for building three-dimensional tooth-and-jaw fusion model

Abstract

The invention discloses a method for building a three-dimensional tooth-and-jaw fusion model. The method includes the steps that data is collected in the occlusion state, and a skull CT image is rebuilt, laser scanning of a gypsum occlusion model is subjected to digital processing; picture processing and the image matching function are based on a reverse engineering software Geomagic Studio, a method based on point matching and the iterative algorithm are combined in the reverse engineering software, a gypsum dentition occlusion model and CT rebuilt dentitions are matched, indistinct CT rebuilt dentitions are replaced, and finally, the three-dimensional tooth-and-jaw fusion model matched in the occlusion state that a CT rebuilt jaw model and the gypsum dentition occlusion model are integrated is obtained. CT imaging artifacts caused by intraoral metal and the error, caused by upper-and-lower-jaw dentition overlapping in the occlusion state, between the occlusion relationship and the practical intraoral occlusion position in the fusion model are reduced, and therefore the accuracy of computer aided design and the treating effect are improved.

Description

technical field [0001] The invention belongs to the technical field of digital modeling, and in particular relates to a method for establishing a three-dimensional tooth-jaw fusion model. Background technique [0002] The three-dimensional dento-jaw fusion model is a digital model composed of at least two different imaging techniques in three-dimensional space, including organizational structures such as dentition, occlusal and maxillofacial bones. [0003] When metal restorations and orthodontic brackets are present, CT images show striated objects and prevent accurate identification of tooth morphology. The dentition needs to be replaced with an optimally simulated upper and lower occlusal relationship and a treatment plan completed. Traditional plaster casts were used to represent the exact dentition and prepare surgical splints. A large number of studies have reported methods for integrating maxillofacial bone models and digital dental models, so that bones, teeth, and...

AI Technical Summary

Problems solved by technology

However, outliers still exist and may affect clinical outcomes, so it is recommended to use the 3D overlay technique for each task after registration validation

[0004] On the one hand, the existing methods for establishing occlusal replacement need to make occlusal reference plates and markers of specific materials and specific parts for each patient, which increases the clinical time of the operator; on the other hand, an occlusal reference plate with a certain thickness and / Or abduct it to be used as a landmark or a marker point, to a certain extent lead to the deformation of facial soft tissues, such as changes in the appearance of lips and cheeks, and finally distort the data of soft tissues; in addition, there is a certain thickness of intraoral occlusal The reference plate will cause the patient to change the position of the bilateral temporomandibular joints when taking CT. For patients with joint problems, it may affect the determination of the treatment plan

[0005] In view of the problems existing in the existing dentition-jaw fusion model, that is, if single-jaw matching is performed in the occlusal state, the upper and lower jaws need to be registered separately. At this time, the manual segmentation of the upper and lower dentition is time-consuming and laborious, and requires high requirements for the operator. It is necessary to be familiar with the shape of the teeth, which is prone to human error; and for some people, it is suggested to perform CT scanning in the non-contact position of the upper and lower jaws, after the upper and lower jaws are registered separately, and then rotate the lower jaw to the occlusal position, so that although the teeth are not manually separated, the lower jaw is rotated There will inevitably be errors during the process, and the rotation axis may not be consistent with the actual situation of the patient, which will ultimately affect the surgical effect; at the same time, the CT scan with the mouth open will inevitably change the normal position of the temporomandibular joint

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