Peri-Implant Biomechanical Responses to Standard, Short-Wide, and Mini Implants Supporting Single Crowns Under Axial and Off-Axial Loading (an In Vitro Study)

2014 ◽  
Vol 40 (1) ◽  
pp. 42-52 ◽  
Author(s):  
Lamia Sayed Kheiralla ◽  
Jihan Farouk Younis
Keyword(s):  
Considerable Increase ◽  
Axial Loading ◽  
In Vitro Study ◽  
Element Analysis ◽  
Mini Implants ◽  
Biomechanical Responses ◽  
Fea Simulation ◽  
Standard Implant ◽  
Single Crowns

This study compared the biomechanical responses of 3 single crowns supported by 3 different implants under axial and off-axial loading. A standard implant (3.75 mm diameter, 13 mm length), a mini implant (3 mm diameter, 13 mm length), and a short-wide implant (5.7 mm diameter, 8 mm length) were embedded in epoxy resin by the aid of a surveyor to ensure their parallelism. Each implant supported a full metal crown made of Ni-Cr alloy with standardized dimensions. Strain gauges and finite element analysis (FEA) were used to measure the strain induced under axial and off-axial functional loads of 300 N. Results showed that mini implants recorded the highest microstrains, under both axial and off-axial loading. All implants showed a considerable increase in strain values under off-axial loading. Standard and short-wide implants proved to be preferable in supporting crowns, as the standard implant showed the lowest strains under axial and off-axial loading using FEA simulation, while the short-wide implant showed the lowest strains under nonaxial loading using strain gauge analysis.

scholarly journals In vitro study of human osteoblast proliferation and morphology on orthodontic mini-implants

2015 ◽  
Vol 85 (6) ◽  
pp. 920-926 ◽  
Author(s):  
Ricardo Carvalho Bueno ◽  
Roberta Tarkany Basting
Keyword(s):  
Chemical Composition ◽  
In Vitro Study ◽  
Chemical Components ◽  
Control Group ◽  
Osteoblast Proliferation ◽  
Mini Implants ◽  
Significant Difference ◽  
Implant Anchorage ◽  
Positive Effect

ABSTRACT Objective:  To evaluate the proliferation and morphology of human osteoblasts cultured on two brands of mini-implants after 24, 48, and 72 hours, in addition to the chemical composition found on their surface. Materials and Methods:  Two brands of mini-implant (Morelli and Neodent) were evaluated; polystyrene was used as a control group (n  =  3). Osteoblasts were cultured on the surface of sterilized mini-implants in a CO2 incubator at different time periods (24, 48, and 72 hours). Osteoblast proliferation was quantified by scanning electron microscopy using up to 5000× magnification, and cell morphology was analyzed by a single observer. For the chemical analysis, spectroscopy X-ray fluorescence was used to identify and quantify chemical components on the surface of the mini-implants. Results:  Two-way ANOVA showed no significant interaction between the factors studied (P  =  0.686). A Tukey test revealed no significant difference in osteoblast proliferation between the mini-implants at all studied periods; however, a difference in cell proliferation was detected between the Neodent and the control group (P  =  .025). For all groups, time had a direct and positive effect on osteoblast proliferation (P < .001). The significant elements present in both brands of mini-implants were titanium, aluminum, vanadium, and iron. Conclusions:  Osteoblast proliferation was present on the mini-implants studied, which increased over time; however, no significant difference between brands was observed. No difference was seen between the mini-implants evaluated in terms of chemical composition. Cell adhesion after 72 hours suggests that areas of bone remodeling can be achieved, thus initiating the process of mini-implant anchorage.

Fixation of distal tibia fracture through plating, nailing, and nailing with Poller screws: A comparative biomechanical-based experimental and numerical investigation

2020 ◽  
Vol 234 (10) ◽  
pp. 1129-1138
Author(s):  
Amin Baseri ◽  
Mohammad Ali Bagheri ◽  
Gholamreza Rouhi ◽  
Mohammad Reza Aghighi ◽  
Nima Bagheri
Keyword(s):  
Distal Tibia ◽  
Axial Loading ◽  
Axial Stiffness ◽  
Element Analysis ◽  
Bone Implant ◽  
Interfragmentary Movement ◽  
Tibia Fractures ◽  
Poller Screw ◽  
Bone Nail

The goal of this study was to investigate two commonly used methods of fixation of distal metaphyseal tibia fractures, plating and nailing as well as the less frequently employed nailing with Poller screws, from a biomechanical perspective. Despite numerous studies, the best method to repair fractures of tibia the remains up for of debate. This study includes an in vitro experimental phase on human cadaveric tibias followed by a finite element analysis. In the experimental phase, under partial weight-bearing axial loading, the axial stiffness of the bone-implant construct and interfragmentary movements for each of the fixation methods, bone-plate, bone-nail, and bone-nail-Poller screw, were measured and compared with each other. Shear interfragmentary movement and stress distribution in the bone-implant construct for the three mentioned fixation methods were also determined from FE models and compared with each other. Results of in vitro experiments, i.e., the exertion of axial loading on the tibia-plate, tibia-nail, and tibia-nail-Poller screw, showed that utilization of tibia-nail and tibia-nail-Poller screw led to a stiffer bone-implant construct, and consequently, lower interfragmentary movement, compared to the tibia-plate construct ( p values for tibia-nail and tibia-nail-Poller screw, and for both axial stiffness and interfragmentary movement, compared to those of tibia-plate construct, were less than 0.05). Numerical analyses showed that nailing produced less undesirable shear interfragmentary movement, compared to the plating, and application of a Poller screw decreased the shear movements, compared to tibia-nail. Furthermore, using the finite element analysis, maximum von Mises stress of adding a screw in tibia-nail, tibia-plate, and tibia-nail-Poller screw, was found to be: 51.5, 78.6, and 60.5 MPa, respectively. The results of this study suggested that from a biomechanical standpoint, nailing both with and without a Poller screw is superior to plating for the treatment of distal tibia fractures.

A Finite Element Analysis of the C2-C7 Sheep Spine

2010 ◽  
Author(s):  
Nicole A. DeVries ◽  
Nicole A. Kallemeyn ◽  
Kiran H. Shivanna ◽  
Nicole M. Grosland
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Surgical Techniques ◽  
In Vitro Studies ◽  
Element Analysis ◽  
Spinal Disorders ◽  
Biomechanical Responses ◽  
Experimental Biomechanics ◽  
Similarities And Differences

Due to the limited availability of human cadaveric specimens, sheep are often utilized for in vitro studies of various spinal disorders and surgical techniques. Understanding the similarities and differences between the human and sheep spine is crucial for constructing a valuable study and interpreting the results. Several studies have identified the anatomical similarities between the sheep and human spine; however these studies have been limited to quantifying the anatomic dimensions as opposed to the biomechanical responses [1–2]. Although anatomical similarities are important, biomechanical correspondence is imperative for studying the effects of disorders, surgical techniques, and implant designs. Studies by Wilke and colleagues [3] and Clarke et al. [4] have focused on experimental biomechanics of the sheep cervical functional spinal units (FSUs).

scholarly journals RETENTION OF MINI SCREWS IN ORTHODONTICS – A COMPARATIVE IN VITRO STUDY ON THE VARIABLES

2021 ◽  
Vol 7 (2) ◽  
pp. 38-42
Author(s):  
Nikhil Asok
Keyword(s):  
Stainless Steel ◽  
Testing Machine ◽  
Compressive Load ◽  
In Vitro Study ◽  
Factors Affecting ◽  
Digital Radiographs ◽  
Mini Implants ◽  
Custom Made ◽  
Load To Failure

Objectives: To correlate between the different lengths, angles of insertion and the mini-implant material and find out the most retentive combination. Materials and methods: 48 mini-implants (24 Titanium and 24 stainless steel) of lengths 6mm, 8mm and 1.5 mm diameter were inserted into humerus bone of goat at two different angulations, 600 and 900. To insert the mini-implant in the respective angulations, custom made template was made and the angles were confirmed with digital radiographs. Force was applied on to the mini-implants with a universal testing machine and the compressive load to failure was measured. Results: Results revealed that stability of the implant was positively correlating with the length of implant. A perpendicular angulation produced more stability. Moreover, titanium mini-implants had more resistance to compressive load than stainless steel mini-implants. Conclusion: Length of mini-implant, its angulation in the bone and the material of mini-implant were factors affecting its stability. In this study, titanium mini-implant of 8mm length angulated at 900 were stable than their counterparts.

scholarly journals Mini-implants for Orthodontic Anchorage: Surface Analysis after Redrilling and Sterilization – An in vitro Study

2016 ◽  
Vol 17 (4) ◽  
pp. 300-305 ◽  
Author(s):  
JM Gross ◽  
GG Nascimento ◽  
VC Araújo ◽  
MJS Bönecker ◽  
C Furuse
Keyword(s):  
Surface Analysis ◽  
In Vitro Study ◽  
Surface Characteristics ◽  
Cleaning Process ◽  
Artificial Bone ◽  
Orthodontic Anchorage ◽  
Synthetic Bone ◽  
Mini Implants ◽  
The Mean

ABSTRACT Objective This study aimed to investigate, in vitro, possible alterations on mini-implants surface after retrieval and if the cleaning process and sterilization can predispose damages. Materials and methods Two commercial mini-implants were tested for deformations after drilling and removing in artificial bone four times. Samples were analyzed by scanning electron microscopy, and surface alterations verified through thread and pitches deformation. To alterations caused by insertion/removal and the cleaning process and sterilization were verified in different procedures: Insertions and sterilization, only insertions, and only sterilization. Photomicrographs were analyzed in order to compare the surface characteristics. Head deformation was verified qualitatively. For a quantitative analysis, distances between threads were measured across the active part of the mini-implants. Results No deformation was observed in both groups. The cleaning and sterilization processes did not provoke alteration in both groups. Nevertheless, the presence of synthetic bone was noted in some samples. The mean distances between implant threads were similar after all steps in all regions in both groups. Conclusion The results suggest that the tested mini-implants can be retrieved without damage of its surface after four cycles of insertion, removal, and sterilization. Clinical significance Mini-implants can be retrieved without damage to its surface after four cycles of insertion, removal, and sterilization in the same patient without representing a biological concern. How to cite this article Gross JM, Nascimento GG, Araújo VC, Bönecker MJS, Furuse C. Mini-implants for Orthodontic Anchorage: Surface Analysis after Redrilling and Sterilization – An in vitro Study. J Contemp Dent Pract 2016;17(4):300-305.

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