scholarly journals Effect of Long-Term Brushing on Deflection, Maximum Load, and Wear of Stainless Steel Wires and Conventional and Spot Bonded Fiber-Reinforced Composites

2019 ◽  
Vol 20 (23) ◽  
pp. 6043 ◽  
Author(s):  
Andrea Scribante ◽  
Pekka Vallittu ◽  
Lippo V. J. Lassila ◽  
Annalisa Viola ◽  
Paola Tessera ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Maximum Load ◽  
Tooth Brushing ◽  
Clinical Use ◽  
Surface Wear ◽  
Fiber Reinforced ◽  
Sem Images ◽  
Similar Reduction ◽  
Bonding Technique

Fiber-reinforced composite (FRC) retainers are an aesthetic alternative to conventional Stainless Steel splints. They are generally used with a full bonded technique, but some studies demonstrated that they could be managed with a spot bonding technique to significantly decrease their rigidity. In order to propose this FRC spot bonding technique for clinical use, the aim of this study was to evaluate mechanical properties and surface wear of fibers left uncovered. Tests were made by simulating tooth brushing, comparing FRC spot bonding technique splints with stainless steel and FRC traditional technique splints. Specimens were tested both at 0.1 mm of deflection and at maximum load, showing higher values of rigidity for the FRC full bonded technique. After tooth brushing, no significant reduction in values at 0.1 mm deflection was reported, while we found a similar reduction in these values for the Stainless Steel and FRC spot bonding technique at maximum load, and no significant variation for the FRC full bonded technique. SEM images after tooth brushing showed wear for FRC fibers left uncovered, while no relevant wear signs in metal and conventional FRC fibers were noticed. Results showed that FRC spot bonding technique has advantages in mechanical properties when compared to the FRC traditional full bonding technique, also after tooth brushing. However, the surface wear after tooth brushing in the FRC spot bonding technique is considerable and other tests must be performed before promoting this technique for routine clinical use.

scholarly journals Glass Fiber Reinforced Composite Orthodontic Retainer: In Vitro Effect of Tooth Brushing on the Surface Wear and Mechanical Properties

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1028 ◽  
Author(s):  
Maria Francesca Sfondrini ◽  
Pekka Kalevi Vallittu ◽  
Lippo Veli Juhana Lassila ◽  
Annalisa Viola ◽  
Paola Gandini ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Resin Composite ◽  
Maximum Load ◽  
Tooth Brushing ◽  
Bending Test ◽  
Bending Stress ◽  
Fiber Reinforced ◽  
Sem Images ◽  
Surface Cover

Fiber reinforced composites (FRCs) are metal free materials that have many applications in dentistry. In clinical orthodontics, they are used as retainers after active treatment in order to avoid relapse. However, although the modulus of the elasticity of FRCs is low, the rigidity of the material in the form of a relatively thick retainer with a surface cover of a flowable resin composite is known to have higher structural rigidity than stainless steel splints. The aim of the present study is to measure load and bending stress of stainless steel wires, as well as flowable resin composite covered and spot-bonded FRC retainer materials after tooth brushing. These materials were tested with a three point bending test for three different conditions: no brushing, 26 min of brushing, and 60 min of brushing. SEM images were taken before and after different times of tooth brushing. Results showed that stainless steel was not significantly affected by tooth brushing. On the other hand, a significant reduction of values at maximum load at fracture was reported for both FRC groups, and uncovered FRCs were most affected. Concerning maximum bending stress, no significant reduction by pretreatment conditions was reported for the materials tested. SEM images showed no evident wear for stainless steel. Flowable resin composite covered FRCs showed some signs of composite wear, whereas spot-bonded FRCs, i.e., without the surface cover of a flowable resin composite, showed signs of wear on the FRC and exposed glass fibers from the FRC’s polymer matrix. Because of the significant changes of the reduction of maximum load values and the wear for spot-bonded FRCs, this technique needs further in vitro and in vivo tests before it can be performed routinely in clinical practice.

Influence of Bond Material Concentration on the Mechanical Properties of Fixed Abrasive Lapping Tool for Stainless Steel

2012 ◽  
Vol 499 ◽  
pp. 372-377
Author(s):  
C.R. Zhu ◽  
B.H. Lv ◽  
Ju Long Yuan
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Shear Strength ◽  
Modulus Of Elasticity ◽  
Stainless Steel Substrate ◽  
Steel Substrate ◽  
Abrasive Tool ◽  
Micro Structure ◽  
Sem Images ◽  
Fixed Abrasive

To improve the machining efficiency as well as surface roughness, a resin-bonded fixed abrasive tool is developed for lapping process of stainless steel substrate. To optimize the lapping ability of the fixed abrasive tool, the influences of bond material concentration on the mechanical properties of fixed abrasive lapping tool, including structure hardness, shear strength, the water-absorbing capacity and modulus of elasticity in compression are investigated. The micro structure of tools is also observed. Tools made of #1000 SiC abrasive and resin with different concentrations is employed in the tests. It is found, the hardness, shear strength, and modulus of elasticity in compression reach highest value, as the 35%wt bond material are used. The water-absorbing capacity increases as the bond material concentration decreases. It is judged from the SEM images that the number of pores in tool with 35%wt bond material is at the most.

A Comparison of the Mechanical Properties of Two External Fixator Designs for Transarticular Stabilization of the Canine Hock

1997 ◽  
Vol 10 (01) ◽  
pp. 54-59 ◽  
Author(s):  
A. D. Pardo ◽  
M. B. Parrott ◽  
J. F. Wassermann ◽  
K. L. Wells
Keyword(s):  
Mechanical Properties ◽  
Clinical Trials ◽  
Stainless Steel ◽  
External Fixator ◽  
Biomechanical Testing ◽  
Maximum Load ◽  
Mode Of Failure ◽  
Load To Failure ◽  
Biomechanical Parameters ◽  
The Mean

SummaryBiomechanical testing was performed on 20 canine tibiotarsal joints. The conventional transarticular external skeletal fixator (ESF) was applied to one rear limb while the alternative design using acrylic was applied to the contralateral rear limb. The mode of failure for all models was fracture of the phalanges at the point of fixation in the distal grip device.The mean stiffness for the acrylic design was 58.5 N/mm and for the conventional ESF 44.8 N/mm. The mean maximum load to failure for the acrylic design was 490.7 N, compared to 405.1 N for the conventional ESF. The angle of deformation at maximum for the acrylic apparatus was 0.45 degrees compared to 2.36 degrees for the standard ESF. The mean energy absorbed to maximum load was 1.92 N-m for the acrylic design and for the conventional ESF 2.69 N-m. This study indicated that the acrylic design was superior in maintaining immobilization across the tibiotarsal joint, indicated by the angle of deformation (p = 0.002) and was structurally comparable in stiffness (p = 0.295), maximum strength (p = 0.438), and total energy absorbed to failure (p = 0.276).The properties of an acrylic and a stainless steel external transarticular skeletal fixator were biomechanically evaluated. Biomechanical parameters evaluated included: maximum load to failure, stiffness, angle of deformation across the tibiotarsal joint, and energy absorbed to failure. The angle of deformation was less (p = 0.002) for the acrylic device. Based on this study, we conclude that the new acrylic design is structurally comparable to the conventional transarticular ESF and warrants clinical trials.

Sign in / Sign up

Export Citation Format

Share Document