Biomechanical Properties of Orthopedic and Dental Implants

Author(s):  
Manjeet Kumar ◽  
Rajesh Kumar ◽  
Sandeep Kumar ◽  
Chander Prakash

The demand for the orthopedic and dental implants has increased sharply in last decade due to physical traumas and age-related deficiencies. The material used for orthopedic and dental implants should be biocompatible to ensure the adaptability of the implant in the human body. The mechanical stability of implants is dependent on mechanical properties and surface characteristics essential to ensure corrosion and wear resistance. The requirement of mechanical properties also differs substantially from load-bearing to non-load-bearing implants. There are many problems arising due to lack of sufficient biocompatibility, like infection, poor osseointegration, and excessive foreign body response. Fatigue failure, stress shielding, and bone resorption are some major problems associated with lack of mechanical stability. Numerous conventional materials, coatings, and nanomaterials have been used to enhance the implant stability.

Author(s):  
Manjeet Kumar ◽  
Rajesh Kumar ◽  
Sandeep Kumar ◽  
Chander Prakash

The demand for the orthopedic and dental implants has increased sharply in last decade due to physical traumas and age-related deficiencies. The material used for orthopedic and dental implants should be biocompatible to ensure the adaptability of the implant in the human body. The mechanical stability of implants is dependent on mechanical properties and surface characteristics essential to ensure corrosion and wear resistance. The requirement of mechanical properties also differs substantially from load-bearing to non-load-bearing implants. There are many problems arising due to lack of sufficient biocompatibility, like infection, poor osseointegration, and excessive foreign body response. Fatigue failure, stress shielding, and bone resorption are some major problems associated with lack of mechanical stability. Numerous conventional materials, coatings, and nanomaterials have been used to enhance the implant stability.


2020 ◽  
Vol 12 (10) ◽  
pp. 1492-1501
Author(s):  
Chengxue Yang ◽  
Zhengwen Yu ◽  
Yuanzhu Long ◽  
Lin Chen

Dental implants have been widely used in clinical practice. The 3D modeling software was used to design threedimensional (3D) models (in the shapes of long strips, discs, and screws), i.e., the Ti2.6Al1.2 V0.42 specimens. Meanwhile, the implant material was electrochemically precipitated, and a layer of chitosan nano-coating was added to the surface. To test the bone-binding ability and planting success rate of the material, the mechanical properties of the specimens with different porosity (0%∼70%) were firstly analyzed by the three-point bending method. Then, the screw-shaped titanium alloy specimens were divided into the solid group, the solid coating group, the solid 30% group, the coating 30% group, the solid 50% group, and the coating 50% group. The MC3T3-E1 cells were cultured, and the in vitro biological properties of the specimens were tested from different angles. The biomechanical properties and flexural strength of screw-shaped titanium alloy specimens in different groups were tested by using a universal testing machine. In the experiment, the prepared dental implants had the complete surface, uniform pore distribution, dense coating distribution, and less overall cracks. The elastic gradient of porous titanium specimens would decrease due to the increase of porosity. The cell activity of the test specimen was higher, and the percentage of viable cells exceeded 80%. The MTT test confirmed that the pores of the test specimen could promote the increase of MTT value (P < 0.05), and the test specimen/composite coating had higher ALP levels compared with the test pieces with no surface treatments (P < 0.05). In biomechanical properties and flexural strength tests, the increase of pores increased the biomechanical properties (P < 0.05) and decreased the flexural resistance (P < 0.05), while the increase of coating decreased the biomechanical properties and increased the flexural resistance (P < 0.05). The porous titanium alloy specimens were successfully prepared, and the chitosan-based composite coating was applied. The material was non-toxic, which was beneficial to cell proliferation and had good mechanical properties, thereby contributing to the growth of new bone.


Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2845
Author(s):  
Michael Gasik ◽  
France Lambert ◽  
Miljana Bacevic

Dental implants’ success comprises their proper stability and adherence to different oral tissues (integration). The implant is exposed to different mechanical stresses from swallowing, mastication and parafunctions for a normal tooth, leading to the simultaneous mechanical movement and deformation of the whole structure. The knowledge of the mechanical properties of the bone and gingival tissues in normal and pathological conditions is very important for the successful conception of dental implants and for clinical practice to access and prevent potential failures and complications originating from incorrect mechanical factors’ combinations. The challenge is that many reported biomechanical properties of these tissues are substantially scattered. This study carries out a critical analysis of known data on mechanical properties of bone and oral soft tissues, suggests more convenient computation methods incorporating invariant parameters and non-linearity with tissues anisotropy, and applies a consistent use of these properties for in silico design and the application of dental implants. Results show the advantages of this approach in analysis and visualization of stress and strain components with potential translation to dental implantology.


2022 ◽  
Author(s):  
Jagannath Padmanabhan ◽  
Kellen Chen ◽  
Dharshan Sivaraj ◽  
Britta A Kuehlmann ◽  
Clark A Bonham ◽  
...  

For decades, it has been assumed that the foreign body response (FBR) to biomedical implants is primarily a reaction to the chemical and mechanical properties of the implant. Here, we show for the first time that a third independent variable, allometric tissue-scale forces (which increase exponentially with body size), can drive the biology of FBR in humans. We first demonstrate that pathological FBR in humans is mediated by immune cell-specific Rac2 mechanotransduction signaling, independent of implant chemistry or mechanical properties. We then show that mice, which are typically poor models of human FBR, can be made to induce a strikingly human-like pathological FBR by altering these extrinsic tissue forces. Altering these extrinsic tissue forces alone activates Rac2 signaling in a unique subpopulation of immune cells and results in a human-like pathological FBR at the molecular, cellular, and local tissue levels. Finally, we demonstrate that blocking Rac2 signaling negates the effect of increased tissue forces, dramatically reducing FBR. These findings highlight a previously unsuspected mechanism for pathological FBR and may have profound implications for the design and safety of all implantable devices in humans.


1992 ◽  
Vol 05 (04) ◽  
pp. 158-162 ◽  
Author(s):  
D. Blackketter ◽  
J Harari ◽  
J. Dupuis

Bone/lateral collateral ligament/bone preparations were tested and structural mechanical properties compared to properties of cranial cruciate ligament in 15 dogs. The lateral collateral ligament has sufficient stiffness to provide stifle joint stability and strength to resist acute overload following fibular head transposition.


Author(s):  
A. E. Chernikova ◽  
Yu. P. Potekhina

Introduction. An osteopathic examination determines the rate, the amplitude and the strength of the main rhythms (cardiac, respiratory and cranial). However, there are relatively few studies in the available literature dedicated to the influence of osteopathic correction (OC) on the characteristics of these rhythms.Goal of research — to study the influence of OC on the rate characteristics of various rhythms of the human body.Materials and methods. 88 adult osteopathic patients aged from 18 to 81 years were examined, among them 30 men and 58 women. All patients received general osteopathic examination. The rate of the cranial rhythm (RCR), respiratory rate (RR) heart rate (HR), the mobility of the nervous processes (MNP) and the connective tissue mobility (CTM) were assessed before and after the OC session.Results. Since age varied greatly in the examined group, a correlation analysis of age-related changes of the assessed rhythms was carried out. Only the CTM correlated with age (r=–0,28; p<0,05) in a statistically significant way. The rank dispersion analysis of Kruskal–Wallis also showed statistically significant difference in this indicator in different age groups (p=0,043). With the increase of years, the CTM decreases gradually. After the OC, the CTM, increased in a statistically significant way (p<0,0001). The RCR varied from 5 to 12 cycles/min in the examined group, which corresponded to the norm. After the OC, the RCR has increased in a statistically significant way (p<0,0001), the MNP has also increased (p<0,0001). The initial heart rate in the subjects varied from 56 to 94 beats/min, and in 15 % it exceeded the norm. After the OC the heart rate corresponded to the norm in all patients. The heart rate and the respiratory rate significantly decreased after the OC (р<0,0001).Conclusion. The described biorhythm changes after the OC session may be indicative of the improvement of the nervous regulation, of the normalization of the autonomic balance, of the improvement of the biomechanical properties of body tissues and of the increase of their mobility. The assessed parameters can be measured quickly without any additional equipment and can be used in order to study the results of the OC.


2015 ◽  
Vol 10 (2) ◽  
pp. 2663-2681
Author(s):  
Rizk El- Sayed ◽  
Mustafa Kamal ◽  
Abu-Bakr El-Bediwi ◽  
Qutaiba Rasheed Solaiman

The structure of a series of AlSb alloys prepared by melt spinning have been studied in the as melt–spun ribbons  as a function of antimony content .The stability  of these structures has  been  related to that of the transport and mechanical properties of the alloy ribbons. Microstructural analysis was performed and it was found that only Al and AlSb phases formed for different composition.  The electrical, thermal and the stability of the mechanical properties are related indirectly through the influence of the antimony content. The results are interpreted in terms of the phase change occurring to alloy system. Electrical resistivity, thermal conductivity, elastic moduli and the values of microhardness are found to be more sensitive than the internal friction to the phase changes. 


2018 ◽  
Vol 69 (5) ◽  
pp. 1272-1275 ◽  
Author(s):  
Camelia Tecu ◽  
Aurora Antoniac ◽  
Gultekin Goller ◽  
Mustafa Guven Gok ◽  
Marius Manole ◽  
...  

Bone reconstruction is a complex process which involves an osteoconductive matrix, osteoinductive signaling, osteogenic cells, vascularization and mechanical stability. Lately, to improve the healing of the bone defects and to accelerate the bone fusion and bone augmentation, bioceramic composite materials have been used as bone substitutes in the field of orthopedics and dentistry, as well as in cosmetic surgery. Of all types of bioceramics, the most used is hydroxyapatite, because of its similar properties to those of the human bone and better mechanical properties compared to b-tricalcium phosphate [1]. Currently, the most used raw materials sources for obtaining the hydroxyapatite are: bovine bone, seashells, corals, oyster shell, eggshells and human teeth. There are two common ways to obtain hydroxyapatite: synthetically and naturally. Generally, for the improvement of the mechanical properties and the structural one, hydroxyapatite is subjected to the sintering process. Considering the disadvantages of hydroxyapatite such as poor biodegradation rate, b-TCP has been developed, which has some disadvantages too, such as brittleness. For this reason, the aim of this study is to look into the effect of adding magnesium oxide on the sintering behavior, the structure and the mechanical properties of the hydroxyapatite-tricalcium phosphate composites.


2017 ◽  
Vol 31 (7) ◽  
pp. 1077-1086 ◽  
Author(s):  
Hanna Jangö ◽  
Søren Gräs ◽  
Lise Christensen ◽  
Gunnar Lose

Alternative approaches to reinforce native tissue in reconstructive surgery for pelvic organ prolapse are warranted. Tissue engineering combines the use of a scaffold with the regenerative potential of stem cells and is a promising new concept in urogynecology. Our objective was to evaluate whether a newly developed long-term degradable polycaprolactone scaffold could provide biomechanical reinforcement and function as a scaffold for autologous muscle fiber fragments. We performed a study with three different rat abdominal wall models where the scaffold with or without muscle fiber fragments was placed (1) subcutaneously (minimal load), (2) in a partial defect (partial load), and (3) in a full-thickness defect (heavy load). After 8 weeks, no animals had developed hernia, and the scaffold provided biomechanical reinforcement, even in the models where it was subjected to heavy load. The scaffold was not yet degraded but showed increased thickness in all groups. Histologically, we found a massive foreign body response with numerous large giant cells intermingled with the fibers of the scaffold. Cells from added muscle fiber fragments could not be traced by PKH26 fluorescence or desmin staining. Taken together, the long-term degradable polycaprolactone scaffold provided biomechanical reinforcement by inducing a marked foreign-body response and attracting numerous inflammatory cells to form a strong neo-tissue construct. However, cells from the muscle fiber fragments did not survive in this milieu. Properties of the new neo-tissue construct must be evaluated at the time of full degradation of the scaffold before its possible clinical value in pelvic organ prolapse surgery can be evaluated.


Sign in / Sign up

Export Citation Format

Share Document