In the paper, using the video image correlation method, a study of the micro-movement pattern of the dental implant and of a normal was performed. It is revealed that there are great differences between these two situations. The linear displacement type of the dental implant refers to the linear elastic modulus of bone tissue in the case of normal bite forces. It seems that the major influencing factor regarding the type and value of implant micro-movement is defined by the underlying bone tissue. It is to be considered that masticator force transmission inside a more stiff and dense bone could be attenuated by the antagonist teeth parodontium, dental implant and abutment connection type, and the elastic modulus of material of the dental crown. Because of the elasticity of the periodontal ligament system, during the loading of the dental implant, the natural tooth has been displaced slightly more, leaving the dental implant in an unfavorable position, having to bear the full amount of loading forces. When comparing the relative displacements in the case of the loaded tooth, it is shown that the dental implant has been moving almost symmetrically with the tooth. This could mean that large amounts of forces are transmitted towards the periimplant bone tissue, but in a more optimal, parabolic manner due to the action of the periodontal ligaments surrounding the natural tooth.
The mechanical properties of the dental filling material (DFMs) strongly influence the lifetime and durability of the tooth reparation performed. Among the most significant mechanical characteristics, one has to mention the Poisson’s ratio and the elastic modulus (Young’s modulus). They, during the cyclic mastication load, can prevent or aid in the prevention of secondary dental decays by provoking micro-cracks, the de-bonding of the filling material from the natural dental tissue, as well as fatigue at the level of their interface. The authors performed a scoping analysis of the nowadays-involved experimental methods, together with a critical review, putting in evidence of their advantages and limits. Based on the developments, they propose a new approach in this sense by involving the electronic speckle pattern interferometry (ESPI)/shearography high-accuracy optical method. They illustrate the advantages of this method in establishment of the elastic modulus, but they also propose a high-accuracy methodology in the estimation of Poisson’s ratio. Based on the briefly-illustrated experimental results, one can conclude that ESPI/shearography can become a very useful tool for research, even though it is not a common (nowadays widely applied) method, such as three-point bending or strain gauge methods.
Introduction: The imaging method of cone beam is an improved, extremely accurate computed tomography applicable in the whole field of dentistry. Due to its ability to locate the exact position of the impacted teeth, CBCT software has an important role in the management of difficult cases of impacted third molar. In some situations, the lower third molar is quite near to the inferior alveolar nerve that the surgical extraction can present a high risk of post-operative sensitive impairs of the skin and mucosa of the lower lip and chin on the same side. Presentation of case series: Our study tried to assess the contribution of CBCT in the pre-operative evaluation and further treatment of patients with impacted third molars in mandibular bone with high risk of inferior alveolar nerve injury. The paper presents three clinical cases showing positive signs on standard OPG, which exhibit indicators of a potential contact between the inferior alveolar nerve and the impacted lower third molars. For an improved exploration Dental CT Scan, DICOM image acquisition program, and 3D reconstruction with a special software were used. Conclusions: The study showed that compared with panoramic radiography, CBCT improve the evaluation of the surgical risk and allow a more accurate planning of surgery.
Possible causes of microleakage and microfractures of dental fillings are often in the center of many academic research and investigations. Some authors found that one important cause of microleakage is the contraction/ shrinkage of the filling materials during polymerization. The purpose of this study is to demonstrate that microcracks and consequent microleakage is influenced by mechanical stresses occurring inside of dental filling materials and at the interface of the dental cavities and dental filling materials. We also tried to evaluate the deformation of some dental filling material types during mechanical loading. Cylindrical specimens were made of different types of dental filling materials, namely microhybrid composites and glass ionomer cement. Some extracted teeth were prepared with class II cavities, and filled. The lateral swelling of the tested specimens and the deformation of the filled teeth during vertical axial loading was measured with an optical method, ESPI/ Shearography.Of the tested specimen, the least deformable dental filling materials were the composite materials. During occlusal vertical loading of the filled teeth, there were found that mechanical stresses were different inside of the filling material than inside of the walls of the dental tissues, mechanical stressed being concentrated at the restoration interface. The ESPI/Shearography meth ode proved to be very useful for investigation in this field. Due to mechanical stresses accumulating at the interface of the dental filling material and the walls of the dental cavity, it is possible that later microcracks to appear due to masticatory forces.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.