The Influence of Prosthesis Design on the Outcomes of Tooth Implants Immediately Placed and Loaded by Means of One-Piece Titanium Machined Restoration

Biomechanical analysis of different fixed dental restorations on short implants: a finite element study

OBJECTIVES

Although the use of short implants is becoming more common for patients with atrophic alveolar ridges, their use is still quite limited. This is due to the lack of data of long-term survival compared to standard-length implants. The aim of this study was to determine the load in the bone and implant system with different superstructures.

METHODS

Three kinds of prosthetic restorations were created on short implants based on CT-Data. Two short implants with different macro-geometries were used. The implants were inserted in idealised posterior lower mandibular segments and afterwards restored with a crown, a double splinted crown, and a bridge.

RESULTS

The analysis was performed under load of 300 N either divided between a mesial and distal point or as a point load on the pontic/mesial crown. The different design of the implant systems had a noticeable influence on the stress in the cortical bone, in the implant system, and the displacement of the superstructure as well.

CONCLUSIONS

Compared with implants of standard length, higher stresses were observed, which can lead early failure of the implant during the healing period or a late cervical bone resorption. Precise indications are essential for short implants to avoid the failure of short implants.

Nursing Research of Optic Canal Decompression Operation under Nasal Endoscopic Medical Treatment Based on Intelligent Internet of Things for Traumatic Vision Disorders

Traumatic vision is an important factor that causes people to have a vision. In our country, the vast majority of vision is caused by trauma. To understand the role of optic nerve decompression in the treatment of traumatic visual disturbances based on the pathological states of traumatic visual disturbances and intelligent Internet of tumors medical nasal endoscopy optic nerve decompression. This article collects relevant information by investigating patients, investigating relevant literature, interviewing professionals, etc., constructing a case template and using a comprehensive quantitative and qualitative analysis method to create a damage assessment matrix. The results of the study found that most traumatic vision disorders occur in the young and middle-aged stage, which is more than three times that of other age groups. The permanent blindness rate of patients reaches 8%, which is extremely harmful. Optic canal decompression surgery can play a great role in the treatment of patients. It can greatly reduce the patient's neurological damage. The effect is about 30% higher than that of general treatment methods, and it can also play a certain role in the prognosis of rehabilitation. It can effectively prevent related postoperative complications. This shows that optic canal decompression in the treatment of traumatic vision disorders should attract people's attention and increase research and development efforts and promotion efforts so that optic canal decompression can be used in the diagnosis and treatment of patients with traumatic vision disorders based on smart Internet of things China can play a greater role.

Augmented Reality Research of Measuring X-Ray Dental Film Alveolar Bone Based on Computer Image Analysis System

The important application of computer imaging technology in the medical field is a necessary auxiliary method for clinical diagnosis and treatment. At present, many people are affected by various factors and have various problems caused by the dental cellular bone. Traditional treatment methods are complex and long, which can cause damage to body tissues. Based on this problem, this paper takes the augmented reality measurement of X-ray dental film as the research object. Based on the in-depth measurement algorithm of the computer image analysis system, two three-dimensional reconstruction methods based on the center of gravity and the matching of the front and side positions are proposed. These two methods only need two X-rays of the front and side of the dental film, the three-dimensional parameters are obtained through calculation and analysis of each spine in the X-ray film, and these parameters are used to fit the dental alveolar bone model. The experimental results prove that the computer-based image analysis system has a great effect on the measurement of X-ray dental film alveolar bone. The positive correlation coefficient reaches 0.87. Compared with the cerebral infarction caused by other methods, the proportion of people with dental film alveolar bone injury is about 15%; after treatment, the functional recovery rate reaches more than 80%. Studies have found that there is a great difference in the age of the population that needs to be treated for dental slices and alveolar bone. The grade of patients is generally under 20 and over 60. This shows that the measurement of X-ray dental film alveolar bone based on computer image analysis system can play an important role in protecting people's oral health.

Biomechanical performance design of joint prosthesis for medical rehabilitation via generative structure optimization

This paper proposes a biomechanical performance design method of joint prosthesis for medical rehabilitation via Generative Structure Optimization (GSO). Firstly, the 3D reconstruction of manifold structure involving hard bone and cartilage is sequentially and progressively implemented from heterogeneous medical images such as Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) via iteration. On the basis of reconstructed mesh structure, the finite element method (FEM) is hereby employed to verify the structure by evaluating the mechanical force distribution. The biomechanical performance design model for 3 D printing (3DP) is then built using multi-objective optimization (MOO) by considering adaptive layer thickness, infill patterns and infill trajectories, etc. The GSO outlets a generative data-driven system which covers various stages such as personalized CT, subsequent 3 D reconstruction, further finite element analysis (FEA) and even structural parameter optimization. The physical experiment of Additive manufacturing (AM) proves that, the relative density, surface topography and wear-resisting performance of joint prosthesis can be improved by GSO which helps to improve biomechanical performance, including kinematics and dynamics. The proposed method may arouse the huge attention in the prosthesis applications to promote patients' high-end customization well-being.

Effect of core materials for core fabrication for dental implants on in-vitro cytocompatibility of MC3T3-E1 cells

Background

Despite the wide use of dental materials for CAD/CAM system in prosthetic treatment, the effect of the materials, which are used as dental implants core fabricated, on cells involved in dental implant osseointegration is uncertain. This study aimed to investigate and compare the effect of single core materials used for dental implants fabricated by the dental prostheses fabrication process and the CAD/CAM milling method on MC3T3-E1 cells.

Methods

The materials used for prostheses restoration in this experiment were Porcelain Fused Gold (P.F.G), Lithium disilicate glass ceramic (LiSi₂), Zirconia (ZrO₂), Nickel-Chromium (Ni-Cr) and Cobalt-Chromium (Co-Cr). MC3T3-E1 cells were cultured and used, the cell adhesion and morphology were observed and analyzed using confocal laser scanning microscopy (CLSM). Methoxyphenyl tetrazolium salt (MTS) and alkaline phosphatase (ALP) assay were used to observe the cell proliferation and differentiation.

Results

CLSM revealed irregular cell adhesion and morphology and the filopodia did not spread in the Ni-Cr specimen group. Significantly high cell proliferation was observed in the ZrO₂ specimen group. The LiSi₂ specimen group presented significantly high cell differentiation. Intergroup comparison of cell proliferation and differentiation between the Ni-Cr specimen group and all other specimen groups showed significant differences (p < .05).

Conclusion

Cell proliferation and differentiation were observed from the cores, which were fabricated with all specimen groups on cytocompatibility except the Ni-Cr specimen group.