Objective To scan and accurately reconstruct mandible models printed via fused deposition modeling(FDM)that contain screw path information,using cone-beam CT(CBCT),to achieve the digital transfer of preoperative model screw paths.Methods CBCT scans were conducted on 12 FDM-printed mandibular models(Model1 group)intended for prebending reconstruction plates.Mim-ics software was employed to reconstruct scanned data into mandibular models(Model2 group)and extract digital screw path informa-tion.Model2 was then compared with original models(Model0 group)in three dimensions,evaluating reconstruction accuracy through root mean square(RMS).Reconstruction parameters were optimized to enable automatic matching of Model2 with Model0,facilitating precise digital transfer of screw paths.In clinical application,this method was utilized to produce digital short-segment drilling guides,assisting in the reduction surgery of three mandibular fracture patients.Results Model2 demonstrated automatic matching with Model0,exhibiting detailed surface characteristics and clear screw path position and orientation information.The RMS was measured at(0.32±0.09)mm.Utilization of digital segmented screw path transfer guides assisted in the satisfactory reduction surgery of three pa-tients with comminuted mandibular fractures.Conclusion CBCT scanning of FDM-printed preoperative models accurately captures screw path position and orientation information,enabling digital transfer of screw paths and providing a novel method for precise design of digital surgical guides.

Objective To scan and accurately reconstruct mandible models printed via fused deposition modeling(FDM)that contain screw path information,using cone-beam CT(CBCT),to achieve the digital transfer of preoperative model screw paths.Methods CBCT scans were conducted on 12 FDM-printed mandibular models(Model1 group)intended for prebending reconstruction plates.Mim-ics software was employed to reconstruct scanned data into mandibular models(Model2 group)and extract digital screw path informa-tion.Model2 was then compared with original models(Model0 group)in three dimensions,evaluating reconstruction accuracy through root mean square(RMS).Reconstruction parameters were optimized to enable automatic matching of Model2 with Model0,facilitating precise digital transfer of screw paths.In clinical application,this method was utilized to produce digital short-segment drilling guides,assisting in the reduction surgery of three mandibular fracture patients.Results Model2 demonstrated automatic matching with Model0,exhibiting detailed surface characteristics and clear screw path position and orientation information.The RMS was measured at(0.32±0.09)mm.Utilization of digital segmented screw path transfer guides assisted in the satisfactory reduction surgery of three pa-tients with comminuted mandibular fractures.Conclusion CBCT scanning of FDM-printed preoperative models accurately captures screw path position and orientation information,enabling digital transfer of screw paths and providing a novel method for precise design of digital surgical guides.

How the brain perceives objects and classifies perceived objects is one of the important goals of visual cognitive neuroscience. Previous research has shown that when we see objects, the brain's ventral visual pathway recognizes and classifies them, leading to different ways of interacting with them. In this paper, we summarize the latest research progress of the ventral visual pathway related to the visual classification of objects. From the perspective of the neural representation of objects and its underlying mechanisms in the visual cortex, we summarize the current research status of the two important organizational dimensions of object animacy and real-world size, provide new insights, and point out the direction of further research.
Brain Mapping/methods* ; Magnetic Resonance Imaging ; Pattern Recognition, Visual ; Photic Stimulation ; Visual Cortex ; Visual Pathways

Objective:To evaluate the feasibility of integrating 3D photos and cone-beam computed tomography (CBCT)images and to assess the degree of error that may occur during the above process,and to analyze soft and hard tissue changes after orthognathic surgery using this new method.Methods:Ten patients with maxillofacial deformities were chosen.For each patient,CBCT scans and stereophotographic images were taken before and 3 months after surgery.3D photos were superimposed onto the CBCT skin im-ages using relatively immobile areas of the face as a reference.3D color maps and mean distances were used to evaluate the errors that might occur during the process.Two reference planes were set up using cer-tain points.The distances between Prn (pronasale),Sn (subnasale),Ls (labrale superior),ANS (anterior nasal spine),A (subspinale),UIE (upper incisor edge)to the coronal plane were calculated before and af-ter surgery.In order to verify the repeatability of this method,we examined the distances twice at two-week intervals.Paired t test was used to evaluate the reproducibility.Results:CBCT and 3D photos could be successfully fused with clinically acceptable errors.This new method could be used to evaluate soft and hard tissue changes after orthognathic surgery.The 3D color maps showed that the two images could be fused with minimal errors.The mean distances were within 0.3 mm,and the locations of landmarks on maxilla and mandible such as Ls,ANS,A,UIE changed significantly after orthognathic surgery (P <0.05). Landmarks on the nose such as Prn,Sn had little changes after surgery (P >0.1 ).The paired t test showed that the mean value and standard deviation were (0.08 ±0.98)mm.Conclusion:Fusing of CBCT and 3D stereophotographic images used as a new method in evaluating soft and hard tissue changes after orthognathic surgery was feasible and accurate.The virtual 3D composite craniofacial models permitted concurrent assess-ment of hard and soft tissues during diagnosis and treatment planning.Maxillary and mandibular locations had significant association with orthoganthic surgery while the nasal tissue was not simp affected by surgery.