Evaluation of stability of three different mini-implants, based on thread shape factor and numerical analysis of stress around mini-implants with different insertion angle, with relation to en-masse retraction force

ABSTRACT Objectives: Assess the stability of three different mini-implants, based on thread shape factor (TSF), and evaluate stresses at the mini-implant site and surrounding cortical bone on application of retraction force, at two different insertion angles. Methods: Mini-implants of three different diameters (M1 - Orthoimplant, 1.8mm), (M2 - Tomas, 1.6mm) and (M3 - Vector TAS, 1.4mm) and length of 8mm were used. Using scanning electronic microscopy, the mean thread depth, pitch and relationship between the two (TSF) were calculated. The mini-implants were loaded into a synthetic bone block and the pull-out strength was tested. One way ANOVA and Tukey post-hoc tests were used to compare the pull-out strength of mini-implants. P values < 0.05 were considered statistically significant. Finite element models (FEM) were constructed with insertion angulation at 90° and 60°, with retraction force of 150 g. The results were analyzed using ANSYS software. Results: Statistically significant difference was found among all the three mini-implants for thread depth and pitch (< 0.001). Statistically significant higher pull-out force value was seen for Orthoimplant. The stress distribution level in mini-implant and surrounding bone was observed to be smaller for Orthoimplant. Conclusion: Orthoimplant mini-implants have more favorable geometric characteristics among the three types, and less stress with 90°angulation.

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Fracture Resistance of Commonly Used Self-drilling Mini-implants of Various Diameters

The Journal of Indian Orthodontic Society ◽

10.1177/0301574219888043 ◽

2020 ◽

Vol 54 (1) ◽

pp. 31-38

Author(s):

Vinodh S. ◽

B. Sangamesh ◽

Neelakantha Patil V. ◽

Sameer Ahmed ◽

Venkat Naidu B.

Keyword(s):

Analysis Of Variance ◽

Fracture Resistance ◽

Insertion Torque ◽

Limited Information ◽

Mini Implants ◽

Significant Difference ◽

Bonferroni Test ◽

Different Diameters ◽

Treatment Procedures ◽

Post Hoc

Context: Self-drilling mini-implants are commonly used in orthodontic treatment procedures, but there is limited information regarding their fracture resistance in areas of high-density bone without predrilling. Aims: The objective of this study is to compare and evaluate the maximum insertion torque and fracture resistance of 3 commonly used self-drilling mini-implants in India, and to assess the influence of variation in diameter in torque generation. Materials and methods: 90 mini-implants from 3 different manufacturers with 2 different diameters were drilled into acrylic blocks using a dial indicating torque screwdriver. All mini-implants were drilled at the rate of 20-30 rotations/min, implants were drilled until they fractured. Torque generated at the point of fracture is shown on the dial of the screwdriver. Measurements of the peak insertion torque value for each manufacturer were recorded separately. Statistical analysis: Analysis of variance, post hoc Bonferroni test. Results: Analysis of variance test showed a significant difference among all the manufacturers in both the diameters with P < .05. Implants of 1.6 mm diameter of Ancer group have the highest fracture resistance value when compared with the same diameter of JJ Orthodontics and SK Surgicals. Implants with higher diameter have more resistance than those with lower diameter. Conclusions: The observed highest fracture resistance is 47 Ncm by Ancer and least fracture resistance is 16 Ncm by JJ Orthodontics. The values are higher than the torque required to place mini-implants intraorally. Ancer mini-implants have the highest peak fracture torque, thus more than SK Surgicals and JJ Orthodontics.

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Temporary Anchorage Device Stability: Monocortical Versus Bicortical Anchorage Technique

UI Proceedings on Health and Medicine ◽

10.7454/uiphm.v1i0.44 ◽

2017 ◽

Vol 1 ◽

Author(s):

Fateen Nur Ain Mohd Azmi ◽

Lim Shuang Ying ◽

Wael Ahmed Bayomy Mohamed ◽

Rozita Hassan

Keyword(s):

Confidence Interval ◽

Bovine Bone ◽

Pull Out ◽

Device Stability ◽

Significant Difference ◽

The Mean ◽

The Stability ◽

Temporary Anchorage Device ◽

Pull Out Strength ◽

One Way Anova

Objective: To compare the stability of splinted and non-splinted miniscrew between monocortical and bicortical anchorage techniques.Methods: Thirty-Six AbsoAnchor orthodontic miniscrews (10mm x 1.5mm) were divided into four groups; non-splinted monocortical, non-splinted bicortical, splinted monocortical and splinted bicortical anchorage techniques. The miniscrews were inserted into sectioned bovine bone blocks and the pull-out strength for each group of miniscrews was measured using Instron 8874; a crosshead speed of 2mm/minute was applied. Six readings were taken for each group and the mean reading for each group was obtained. The data was analyzed using one-way ANOVA test with 95% confidence interval (P<0.05).Results: The pull-out strength mean of splinted group was observed to be statistically higher than non-splinted. The mean of the pull-out strength of bicortical was higher than monocortical in both splinted and non-splinted groups, however it is not significant.Conclusion: Both splinted monocortical and bicortical anchorage miniscrews were significantly stable than non-splinted counterpart. However, in monocortical and bicortical anchorage, there was no significant difference of the pull-out strength between splinted and non-splinted miniscrews.

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Effects of placement angle and direction of orthopedic force application on the stability of orthodontic miniscrews

The Angle Orthodontist ◽

10.2319/090112-703.1 ◽

2012 ◽

Vol 83 (4) ◽

pp. 667-673 ◽

Cited By ~ 16

Author(s):

Jihye Lee ◽

Ji Young Kim ◽

Yoon Jeong Choi ◽

Kyung-Ho Kim ◽

Chooryung J. Chung

Keyword(s):

Cortical Bone ◽

Lateral Force ◽

Von Mises Stress ◽

Biomechanical Stability ◽

Element Analysis ◽

Force Application ◽

Pull Out ◽

The Stability ◽

Von Mises ◽

Pull Out Strength

ABSTRACT Objectives: To evaluate the influence of placement angle and direction of orthopedic force application on the stability of miniscrews. Materials and Methods: Finite element analysis was performed using miniscrews inserted into supporting bone at angles of 90°, 60°, and 30° (P90°, P60°, and P30°). An orthopedic heavy force of 800 gf was applied to the heads of the miniscrews in four upward (U0°, U30°, U60°, U90°) or lateral (L0°, L30°, L60°, L90°) directions. In addition, pull-out strength of the miniscrews was measured with various force directions and cortical bone thicknesses. Results: Miniscrews with a placement angle of 30° (P30°) and 60° (P60°) showed a significant increase in maximum von Mises stress following the increase in lateral force vectors (U30°, U60°, U90°) compared to those with a placement angle of 90° (P90°). In accordance, the pull-out strength was higher with the axial upward force when compared to the upward force with lateral vectors. Maximum von Mises stress and displacement of the miniscrew increased as the angle of lateral force increased (L30°, L60°, L90°). However, a more dramatic increase in maximum von Mises stress was noted in P30° than in P60° and P90°. Conclusion: Placement of the miniscrew perpendicular to the cortical bone is advantageous in terms of biomechanical stability. Placement angles of less than 60° can reduce the stability of miniscrews when orthopedic forces are applied in various directions.

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The Stability of Temporary Restorations Fabricated on a Healing Cap for Immediate Loading: An In Vitro Study

Applied Sciences ◽

10.3390/app8112261 ◽

2018 ◽

Vol 8 (11) ◽

pp. 2261

Author(s):

Sangho Jun ◽

Hyonseok Jang ◽

Enji Cheon ◽

MinJu Kim ◽

Sungwon Ju ◽

...

Keyword(s):

Compressive Strength ◽

Load Distribution ◽

In Vitro Study ◽

Bite Force ◽

Immediate Loading ◽

Pull Out ◽

The Stability ◽

Implant Treatment ◽

Pull Out Strength

The aim of this study was to analyze the load distribution of interim restorations using healing cap during immediate loading implant treatment in vitro. A total of 29 models with interim restorations which were fabricated with healing cap were selected. The pull-out strength was measured with a used healing cap and new healing cap. The compressive strength and sinking distance were also measured. The pull-out strength of interim restoration showed lower value (max. 29.8 N) compared to the natural bite force. The sinking amounts were larger than normal tooth sinking. The sinking amounts of interim restorations fabricated on a healing cap were roughly 3 times (0.3–0.5 mm under 450 N) those of normal teeth. The interim restoration on plastic healing cap would be useful for immediate loading implant treatment.

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Cyclic Testing of Flexible All-Inside Meniscus Suture Anchors: Biomechanical Analysis

The American Journal of Sports Medicine ◽

10.1177/0363546504271204 ◽

2005 ◽

Vol 33 (3) ◽

pp. 388-394 ◽

Cited By ~ 51

Author(s):

Thore Zantop ◽

Ann K. Eggers ◽

Volker Musahl ◽

Andre Weimann ◽

Wolf Petersen

Keyword(s):

Cyclic Loading ◽

Biomechanical Properties ◽

Meniscus Repair ◽

Biomechanical Analysis ◽

Suture Techniques ◽

Suture Anchors ◽

Pull Out ◽

Meniscus Suture ◽

Significant Difference ◽

Pull Out Strength

Background Flexible meniscus repair devices are designed to combine the benefits of rigid all-inside meniscus anchors with the biomechanical properties of sutures. Hypothesis Stiffness and pull-out strength of flexible all-inside suture anchors and conventional sutures under cyclic loading conditions will be comparable. Study Design Controlled laboratory study Methods In 50 fresh frozen bovine menisci, artificial meniscus lesions were repaired with different meniscus fixation techniques: horizontal and vertical FasT-Fix, RapidLoc, and horizontal and vertical 2-0 Ethibond sutures. The specimens were cycled 1000 times between 5 and 20 N and then loaded to failure. Results All devices survived the cyclic loading protocol. There was no significant difference in the displacement between all repair techniques tested (horizontal FasT-Fix, 6.23 mm; vertical FasT-Fix, 5.34 mm; RapidLoc, 6.84 mm; horizontal 2-0 Ethibond, 6.03 mm; vertical 2-0 Ethibond, 5.61 mm (P >. 05). Vertical and horizontal FasT-Fix suture anchors had a significantly higher stiffness and pull-out strength (94.1 N and 80.8 N, respectively) than did horizontal sutures (50.2 N) and RapidLoc devices (30.3 N) (P >. 05). Conclusions In this study, flexible all-inside meniscus anchors (FasT-Fix) had higher pull-out strength than did conventional vertical suture techniques. Biomechanical characteristics of the flexible RapidLoc are comparable to those of horizontal sutures. Clinical Relevance Flexible all-inside meniscus repair devices are an alternative to conventional suture techniques.

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Efficacy of titanium brush, 915 nm diode laser, citric acid for eradication of Staphylococcus aureus from implant surfaces

BMC Oral Health ◽

10.1186/s12903-021-01997-z ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Mohammad Reza Karimi ◽

Behshad Farkhondemehr ◽

Motahare Ghaeni Najafi ◽

Ardavan Etemadi ◽

Nasim Chiniforush

Keyword(s):

Staphylococcus Aureus ◽

Citric Acid ◽

Diode Laser ◽

Acid Group ◽

Negative Control ◽

Control Groups ◽

Implant Surface ◽

Mini Implants ◽

Significant Difference ◽

Post Hoc

Abstract Background This study aimed to assess the efficacy of titanium brush, 915 nm diode laser, citric acid and the combination of latter two with titanium brush for decontamination of SLA surface mini-implants. Methods Seventy-five mini-implants contaminated with Staphylococcus aureus (S. aureus) were randomly divided into five experimental groups (n = 12) of titanium brush (TiB), laser, citric acid (CA), brush-laser, and brush-acid, positive [n = 12; chlorhexidine mouthwash (CHX)] and negative [n = 2; phosphate buffered saline (PBS)] control groups and one no-treatment group (n = 1). After counting the colony forming units (CFUs), data were analyzed using the Kruskal–Wallis and Dunn post-hoc tests. Results Regardless of the no-treatment and negative control groups, maximum and minimum CFUs were noted in the titanium brush and positive control groups. After CHX, minimum CFUs were noted in brush-acid group followed by brush-laser, laser, and acid groups. Generally, the Kruskal–Wallis test revealed a significant difference between the groups regarding the colony count (P < 0.001). Dunn post-hoc test showed that the difference between the titanium brush and acid-brush group was significant (P < 0.001) while the differences between the brush and laser groups with the brush-laser group were not significant (P > 0.077). Conclusions Combined use of titanium brush and citric acid yielded superior results compared to other groups in reduction of S. aureus on implant surface.

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Axial pull-out strength of 3.5 cortical and 4.0 cancellous bone screws placed in canine proximal tibias using manual and power tapping

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.3415/vcot-07-08-0082 ◽

2008 ◽

Vol 21 (04) ◽

pp. 323-328 ◽

Cited By ~ 4

Author(s):

M. E. Soniat ◽

S. Elder ◽

R. McLaughlin ◽

J. L. Demko

Keyword(s):

Cancellous Bone ◽

Testing Machine ◽

Bone Screws ◽

Materials Testing ◽

Pull Out ◽

Cortical Width ◽

Bone Width ◽

Significant Difference ◽

Pull Out Strength

SummaryAn in vitro experimental cadaveric mechanical testing study was performed using 20 radiographically mature dogs, weighing between 18–33 kg. The aim of the study was to compare the axial pull-out strength of 3.5 mm cortical and 4.0 mm cancellous bone screws inserted in the canine proximal tibia using manual and power tapping techniques. 3.5 cortical and 4.0 cancellous bone screws were inserted in canine cadaver proximal tibiae using a manual or power tapping technique. The screws were extracted using a servohydraulic materials testing machine in order to measure axial pullout strength. Axial pull-out strength was recorded relative to the total bone width and total cortical width of each tibia. The mean axial pull-out strength for all constructs was 717.8±56.5 N without any statistically significant difference among groups (p=0.4183). The groups were equal in animal body weight, cortical width and total bone width (p=0.2808). The axial pull-out strength in proportion to cortical and total bone width was not significantly different among groups (p=0.5318). Axial pull-out strengths of 3.5 mm cortical and 4.0 mm cancellous bone screws inserted in the proximal tibial metaphysis were not significantly different. Axial pull-out strength was not affected by the use of power tapping in either screw type.

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