Surface Characteristics of Esthetic Nickel–Titanium and Beta-Titanium Orthodontic Archwires Produced by Plasma Electrolytic Oxidation (PEO)—Primary Results

Abstract

Background/Aim: There is continuing interest in engineering esthetic labial archwires. The aim of this study was to coat nickel–titanium (NiTi) and beta-titanium (β-Ti), also known as titanium molybdenum (TMA), archwires by plasma electrolytic oxidation (PEO) and to analyze the characteristics of the PEO-surfaces. Materials and Methods: PEO-coatings were generated on 0.014-inch NiTi and 0.19 × 0.25-inch β-Ti archwires. The surfaces were analyzed by scanning electron microscopy and stereomicroscopy. Cytocompatibility testing was performed with ceramized and untreated samples according to EN ISO 10993-5 in XTT-, BrdU- and LDH-assays. The direct cell impact was analyzed using LIVE-/DEAD-staining. In addition, the archwires were inserted in an orthodontic model and photographs were taken before and after insertion. Results: The PEO coatings were 15 to 20 µm thick with a whitish appearance. The cytocompatibility analysis revealed good cytocompatibility results for both ceramized NiTi and β-Ti archwires. In the direct cell tests, the ceramized samples showed improved compatibility as compared to those of uncoated samples. However, bending of the archwires resulted in loss of the PEO-surfaces. Nevertheless, it was possible to insert the β-Ti PEO-coated archwire in an orthodontic model without loss of the PEO-ceramic. Conclusion: PEO is a promising technique for the generation of esthetic orthodontic archwires. Since the PEO-coating does not resist bending, its clinical use seems to be limited so far to orthodontic techniques using straight or pre-bent archwires.

Evaluation of effectiveness of low level laser therapy in accelerating orthodontic tooth movement-An in vivo study

“…This localized effect helps to concentrate only on areas that need to be treated. 2 At times, corticotomies has proven to improve the orthodontic movements by increased stimulation; but with a disadvantage that they can be performed only along the areas with cortical portions of the alveolar bone. Also there is lesser patient compliance due to the surgical procedure involved merely for an accelerated tooth movement.…”

“…1 Prolonged orthodontic management prods a lot of patients, Orthodontists are trying since long to develop certain approach strategies that will actually assist to increase the rate at which the tooth movement takes place during orthodontic treatment. 2,3 The rate of tooth movement per se can be accelerated by administration of drugs such as prostaglandins, electrical stimulations, vitamin D and osteocalcin, use of ultrasound around the sockets in the jaws. The injection method is always accompanied by certain degree of pain as well as discomfort to the patients.…”

Esthetic nickel titanium wires– Do they deliver the same force?

“…1 There is a growing demand for esthetic appliances, but most fixed orthodontic appliance components are metallic and silver in color. 2,3 This problem has been partially solved by the introduction of esthetic brackets made of ceramic or composite, which are becoming more popular. 3,4 However, archwires are still made of metals such as stainless steel and nickel titanium (NiTi).…”

“…Coating metallic archwires with plastic resin materials is currently the only existing solution to this aesthetic problem. 2 Materials used in the coating process are Teflon® or epoxy resin. The process of applying this layer includes using clean compressed air as a transport medium for the atomized Teflon® particles to coat the wire which is further heat treated in a chamber furnace.…”

“…The process of applying this layer includes using clean compressed air as a transport medium for the atomized Teflon® particles to coat the wire which is further heat treated in a chamber furnace. 2 Some researchers found that plastic coating decreased friction between archwires and brackets. 5 On the contrary, Proffit (2000) described this coat as undurable.…”