Differences in the force system delivered by different beta-titanium wires in elaborate designs

Abstract

Objective: Evaluation of the force system produced by four brands of b-Ti wires bent into an elaborate design. Methods: A total of 40 T-loop springs (TLS) hand-bent from 0.017 x 0.025-in b-Ti were randomly divided into four groups according to wire brand: TMATM(G1), BETA FLEXYTM (G2), BETA III WIRETM (G3) and BETA CNATM (G4). Forces and moments were recorded by a moment transducer, coupled to a digital extensometer indicator adapted to a testing machine, every 0.5 mm of deactivation from 5 mm of the initial activation. The moment-to-force (MF) ratio, the overlapping of the vertical extensions of the TLSs and the load-deflection (LD) ratio were also calculated. To complement the results, the Young's module (YM) of each wire was determined by the slope of the load-deflection graph of a tensile test. The surface chemical composition was also evaluated by an energy dispersive X-ray fluorescence spectrometer. Results: All groups, except for G2, produced similar force levels initially. G3 produced the highest LD rates and G1 and G4 had similar amounts of overlap of the vertical extensions of the TLSs in "neutral position". G1 and G3 delivered the highest levels of moments, and G2 and G3 produced the highest MF ratios. b-Ti wires from G3 produced the highest YM and all groups showed similar composition, except for G2. Conclusion: The four beta-titanium wires analyzed produced different force systems when used in a more elaborate design due to the fact that each wire responds differently to bends.

A Review of Metastable Beta Titanium Alloys

“…One disadvantage of the TMA alloys is its propensity to fracture and some studies have examined the biocompatibility, corrosion resistance, and fracture characteristics of these alloys [88]. The expiration of the patent for the TMA alloy has led to the introduction of many modified TMA alloys that are being evaluated for use in orthodontic devices and wires [89][90][91][92]. More recently, a study by Hida et al, has reported on the development of the experimental near-beta Ti-6Mo-4Sn (wt.…”

Evaluation of the load system produced by a single intrusion bend in a maxillary lateral incisor bracket with different alloys

“…This was probably due to a change in the shape of the orthodontic arch as the active bend was inserted into the brackets, such as what happens to orthodontic loops in their neutral position. 30 This deflection associated with the amount of wire added between the brackets by the bend probably produced this side effect. In addition, a normal force not perfectly vertical from the archwire acting on the bracket could produce buccolingual forces if the slots were not entirely parallel to the transverse plane.…”

Effect of stress relaxation in two different preactivation methods of beta-titanium T-loops: bends vs. continuous curvature

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