Bovine cortical bone ablation by femtosecond laser (Conference Presentation)

2018 ◽  
Author(s):  
Fahad Aljekhedab ◽  
Wenbin Zhang ◽  
Jonathan Favero ◽  
Harold K. Haugen ◽  
Gregory R. Wohl ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Cortical Bone

Femtosecond laser ablation of bovine cortical bone

2012 ◽  
Vol 17 (12) ◽  
pp. 125005 ◽  
Author(s):  
Liliana T. Cangueiro ◽  
Rui Vilar ◽  
Ana M. Botelho do Rego ◽  
Vania S. F. Muralha
Keyword(s):  
Laser Ablation ◽  
Femtosecond Laser ◽  
Cortical Bone ◽  
Femtosecond Laser Ablation

Micropillar fabrication on bovine cortical bone by direct-write femtosecond laser ablation

2009 ◽  
Vol 14 (6) ◽  
pp. 064021 ◽  
Author(s):  
Yong C. Lim ◽  
Katrina J. Altman ◽  
Dave F. Farson ◽  
Katharine M. Flores
Keyword(s):  
Laser Ablation ◽  
Femtosecond Laser ◽  
Cortical Bone ◽  
Femtosecond Laser Ablation ◽  
Direct Write

scholarly journals Effects of Drilling Technology on Mini-Implant Primary Stability: A Comparison of the Mechanical Drilling and Femtosecond Laser Ablation

2021 ◽  
Vol 9 ◽  
Author(s):  
Wenbin Zhang ◽  
Fahad Alghannam ◽  
Yingchao Zhu ◽  
Jianfei Zhang ◽  
Gregory R Wohl ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Femtosecond Laser ◽  
Cortical Bone ◽  
Primary Stability ◽  
Femtosecond Laser Ablation ◽  
Site Preparation ◽  
Pull Out ◽  
Subgroup Ii ◽  
Drilling Technology ◽  
Pull Out Strength

Objectives: Primary stability is a fundamental prerequisite in predicting the prognosis of a mini-implant (MI) as a skeletal anchorage. This study aims to evaluate the influence of implant site preparation technology on the primary stability of MI.Methods: A total of 108 bovine cortical bone samples were fabricated to three thicknesses (0.5, 1.0, and 1.5 mm). For each thickness group, the samples were divided into three subgroups: I (without site preparation), II (site preparation with a mechanical drill), and III (site preparation with femtosecond laser ablation). After MI insertion into these samples, the pull out strength of MI was measured by lateral pull out tests.Results: For the 0.5 mm thickness samples, the lateral pull-out strength was 9.9±2.7 N in subgroup I, 6.7±2.1 N in subgroup II, and 15.2±2.6 N in subgroup III. For the 1.0 mm thickness samples, the lateral pull-out strength was 39.3±2.5N in subgroup I, 38.2±2.7N in subgroup II, and 46.3±1.7 N in subgroup III. For the 1.5 mm thickness samples, the lateral pull-out strength was 73.9±4.8 N in subgroup I, 70.1±2.8 N in subgroup II, 75.0±2.2 N in subgroup III. No signs of carbonization or substantial cracking were visible in any of the bone samples.Conclusion: Site preparation with laser ablation significantly improved the lateral pull-out strength over mechanical preparation and control (no site preparation) in thinner cortical bone samples (1.0 and 0.5 mm). Such improvement in lateral pull-out strength decreases as the samples become thicker and diminishes in thick (1.5 mm) cortical bone samples.

Nanosecond laser-induced breakdown assisted by femtosecond laser pre-ionization in air: the effect on spatial resolution and continuous radiation

2020 ◽  
Vol 92 (2) ◽  
pp. 20701
Author(s):  
Bo Li ◽  
Xiaofeng Li ◽  
Zhifeng Zhu ◽  
Qiang Gao
Keyword(s):  
Femtosecond Laser ◽  
Spatial Resolution ◽  
Laser Induced Breakdown Spectroscopy ◽  
Nanosecond Laser ◽  
Breakdown Threshold ◽  
Powerful Technique ◽  
Breakdown Spectroscopy ◽  
Continuous Radiation ◽  
Laser Induced Breakdown

Laser-induced breakdown spectroscopy (LIBS) is a powerful technique for quantitative diagnostics of gases. The spatial resolution of LIBS, however, is limited by the volume of plasma. Here femtosecond-nanosecond dual-pulsed LIBS was demonstrated. Using this method, the breakdown threshold was reduced by 80%, and decay of continuous radiation was shortened. In addition, the volume of the plasma was shrunk by 85% and hence, the spatial resolution of LIBS was significantly improved.

Pullout Strength of Screws in Foal Third Metacarpal Bone after Overdrilling a 4.5 mm Hole

1998 ◽  
Vol 11 (04) ◽  
pp. 200-204 ◽  
Author(s):  
K. Kelly ◽  
G. S. Martin ◽  
D. J. Burba ◽  
S. A. Sedrish ◽  
R. M. Moore
Keyword(s):  
Cortical Bone ◽  
Metacarpal Bone ◽  
Pullout Strength ◽  
Cancellous Screw ◽  
Bone Screw ◽  
Screw Insertion ◽  
Holding Power ◽  
Cortical Screw ◽  
Metaphyseal Bone

SummaryThe purpose of the study was to determine and to compare the in vitro pullout strength of 5.5 mm cortical versus 6.5 mm cancellous bone screws inserted in the diaphysis and metaphysis of foal third metacarpal (MCIII) bones in threaded 4.5 mm cortical bone screw insertion holes that were then overdrilled with a 4.5 mm drill bit. This information is relevant to the selection of a replacement screw if a 4.5 mm cortical screw is stripped during orthopaedic surgery. In vitro pullout tests were performed in two independent cadaver studies, each consisting of 12 foal MCIII bones. Two 4.5 mm cortical screws were placed either in the mid-diaphysis (study 1) or distal metaphysis (study 2) of MCIII bones. The holes were then overdrilled with a 4.5 mm bit and had either a 5.5 mm cortical or a 6.5 mm cancellous screw inserted; screw pullout tests were performed at a rate of 0.04 mm/s until screw or bone failure occurred.The bone failed in all of the tests in the diaphyseal and metaphyseal bone. The holding power for 6.5 mm cancellous screws was significantly (p <0.05) greater than for 5.5 mm cortical screws in both the diaphysis and metaphysis. There was not any difference in the holding power of screws in either the diaphysis or the metaphysis between proximal and distal screw holes.If a 4.5 mm cortical bone screw strips in MCIII diaphyseal or metaphyseal bone of foals, a 6.5 mm cancellous screw would provide greater holding power than a 5.5 mm cortical screw.In order to provide information regarding selection of a replacement screw if a 4.5 mm cortical screw is stripped, the in vitro pullout strength was determined for 5.5 mm cortical and 6.5 mm cancellous screws inserted in third metacarpal diaphyseal and metaphyseal bone of foals in which threaded 4.5 mm cortical bone screw insertion holes had been overdrilled with a 4.5 mm bit. The holding power of the 6.5 mm cancellous screw was significantly greater than the 5.5 mm cortical screw in both the diaphysis and metaphysis of foal third metacarpal bone. Thus, it appears that if a 4.5 mm cortical screw is stripped during orthopaedic surgery in foals, a 6.5 mm cancellous screw would provide superior holding power.

Glucocorticoid-induced loss of cortical bone is exacerbated during cold-exposure in male mice

2019 ◽  
Author(s):  
M Gado ◽  
M Noll ◽  
A Heinrich ◽  
M Rauner ◽  
LC Hofbauer ◽  
...  
Keyword(s):  
Cortical Bone ◽  
Cold Exposure ◽  
Male Mice
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