“Fretting Damage of Coil Spring”

Open-Coil Retraction Spring

Sliding mechanic has become a popular method for space closure with developments in preadjusted edgewise appliance. Furthermore, various space closing auxiliaries have been developed and evaluated extensively for their clinical efficiency. Their effectiveness enhanced with optimum force magnitude and low-load deflection rate (LDR)/force decay. With the advent of NiTi springs in orthodontics, LD...

Spring coil retraction in coil occlusion of persistent ductus arteriosus.

AIMS To present the short and intermediate term results of coil occlusion of persistent ductus arteriosus and the results of radiographic measurements of spring coils implanted to treat patent ducts. PATIENTS 22 children underwent coil occlusion. Their ages ranged from 2 years 9 months to 12 years 10 months (mean (SD) age, 6.5 (3.6) years). The duct diameter ranged from 1.0 to 3.5 mm at the n...

Design and Analysis of Two Wheeler Shock Absorber Coil Spring

Miniscrew-supported coil spring for molar uprighting: description.

INTRODUCTION Since the beginning of miniscrews as orthodontic anchorage, many applications have been described in the literature. Among these, one is the uprighting of mesially inclined molars. In regard to the mechanical aspects, however, there is little information about the application of orthodontic forces using such devices. OBJECTIVE The objective of this study was to describe a miniscr...

Some considerations on the mitigation of fretting damage by the application of surface-modi®cation technologies

Fretting is a surface-degradation process due to mechanical and chemical attack by small-amplitude oscillatory movement between two contacting surfaces and it is intimately related to wear, corrosion and fatigue. The introduction of surface treatments or coatings is expected to be an effective strategy against fretting damage. This paper discusses the application of several types of advanced su...