A New Method And Related Research On The Establishment Of Three Dimensional Model Of Dentition-jaw Fusion

Computer aided technology can provide a better function and aesthetic effect for the surgical operation, and the improvement of the patient’s information is the premise of the design of the treatment plan. The establishment of 3D fusion model, can reflect the patient’s jaw face effective information(including facial soft tissue morphology, jaw morphology and tooth column occlusal patterns, etc.) of a variety of data collection methods in all directions to combine. However, the existing methods of establishing three-dimensional fusion model are time-consuming and laborious, and the requirements of the operator are high, and the error is easy to occur. Objective:In this study, in view of the existing 3D dental fusion model building method of the existing problems, to explore a new normal occlusion operation simple easy registration of 3D dental fusion model establishment method, and for evaluation of the established model fusion accuracy. On the basis of this, the limitation of mouth opening were collected teeth column information method research, establishment of a segmented mold computer registration combination obtain complete dentition model method, and this method accuracy was evaluated and provide guidance for its clinical application. Methods:1. We selected 17 patients and 10 complete dentition plaster models of the patients admitted in our hospital from February to April 2015. Patients’ cranial CT image information and intraoral impressions cast model had been collected. the jaw and dentition had been reconstructed in the Mimics, and the gypsum models had been scanned by laser. In the Geomagic studio on CT reconstruction and dentition plaster occlusion model was based on the manual registration and global registration algorithm based on, the occlusal casts of alternative CT reconstruction dentition data, and through the Boolean operation with the upper and lower jaws with, establishment of the complete fusion model of 3D dental.2. The new fusion model of partial occlusion into mimics, marked contour, group 1; to single jaw plaster model and CT reconstruction of artificial tooth segmentation contour registration from the bite location set to 2 groups, compared with the teeth in the original CT image column position, modeling and evaluation of the accuracy of the model.3. On 10 complete plaster tooth column model according to clinical operation requirements section modulus, the subsection model of laser scanning, in Geomagic studio will be piecewise model is classified according to different contact tooth position for three kinds of modeling method, registration, respectively, after a complete dentition, and compare with the three-dimensional integrated model and to evaluate its accuracy. Results:1. Through the processing of the skull CT image data and digital plaster model data, based on the reverse engineering software registration algorithm, can be obtained in the occlusal state registration of three-dimensional dental fusion model.2. By comparing the data of the group 1, group 2 and CT in mimics, the smallest observation error of the model articulation model is 0.044 mm ± 0.083 mm, the maximum observation error is 0.286mm±0.1mm. Occlusal model and single jaw registration model two kinds of modeling methods in skeletal Class II malocclusion deformity in the maxillary incisors, canines in two registration methods no statistical difference(P > 0.05); There are differences of maxillary molar and mandibular incisors, canines and molars in two registration methods(P < 0.05); skeletal Class III malocclusion deformity in mandibular incisor, canine and incisor no statistical difference(P > 0.05); mandibular molar, maxillary canines and molars in the two registration methods exist difference(P < 0.05).3. The method of obtaining the complete dentition model by the combination of computer registration and registration is established. To compare the combined model with initial model, the smallest error observed was 0.046 mm±0.055 mm and the largest error observed was 0.032mm±0.115 mm. There was no statistical difference between three methods. Conclusion:The model column registration through the plaster model and CT reconstruction of occlusal teeth, get a bite in the condition of compounded 3D dentition jaw fusion model, and comparing with the single jaw registration model, a preliminary validation of the new 3D dental model precision can be used in clinical practice, in order to solve the tooth CT image is not clear, there are artifacts and other issues and provides a new method. As an extension of the application of this model, this study established a method of subsection modulo computer registration combined to obtain complete dentition model, and verify its accuracy, this modeling method can obtain accurate complete tooth meet clinical application of column model, and is expected to solve the mouth limited collection of patients with complete dentition model the problems.