Mechanical properties of NiTi and CuNiTi wires used in orthodontic treatment. Part 2: Microscopic surface appraisal and metallurgical characteristics.

Objective: This research aimed at comparing the qualitative chemical compositions and the surface morphology of fracture regions of eight types of Nickel/Titanium (NiTi) conventional wires, superelastic and heat-activated (GAC, TP, Ormco, Masel, Morelli and Unitek), to the wires with addition of copper (CuNiTi 27ºC and 35ºC, Ormco) after traction test.

Methods: The analyses were performed in a scanning electronic microscope (JEOL, model JSM-5800 LV) with EDS system of microanalysis (energy dispersive spectroscopy).

Results: The results showed that NiTi wires presented Ni and Ti as the main elements of the alloy with minimum differences in their composition.

Clinical evaluation of dental alignment and leveling with three different types of orthodontic wires.

Introduction: A wide variety of orthodontic wires made of different alloys is available to be used in orthodontic practice and may produce different clinical responses during tooth movement.

Objective: This research evaluated the alignment and leveling of lower dental arches after the use of three types of orthodontic wires.

Methods: A sample of 36 patients was randomly divided into 3 groups: stainless steel, multistranded steel and superelastic nickel-titanium, according to the first leveling arches used.

Mechanical properties of NiTi and CuNiTi shape-memory wires used in orthodontic treatment. Part 1: stress-strain tests.

Objective: This research aimed to compare, through traction tests, eight types of superelastic and heat-activated NiTi archwires, by six trade companies (GAC, TP, Ormco, Masel, Morelli and Unitek) to those with addition of copper (CuNiTi 27°C and 35°C, Ormco).

Methods: The tests were performed in an EMIC mechanical testing machine, model DL10000, capacity of 10 tons, at the Military Institute of Engineering (IME).

Results: The results showed that, generally, heat-activated NiTi archwires presented slighter deactivation loadings in relation to the superelastic ones.

Influence of surface treatment on shear bond strength of orthodontic brackets.

Introduction: The shear bond strength of orthodontic brackets bonded to micro-hybrid and micro-particulate resins under different surface treatment methods was assessed.

Methods: Two hundred and eighty test samples were divided into 28 groups (n = 10), where 140 specimens were filled with Durafill micro-particulate resin and 140 with Charisma composite. In 140 samples, a coupling agent (silane) was applied.

Surgical treatment of dental and skeletal Class III malocclusion.

Orthodontic preparation for surgical treatment of skeletal Class III malocclusion involves joint planning with an oral and maxillofacial surgeon to address the functional and esthetic needs of the patient. In order to allow surgical manipulation of the jaws in the preoperative phase, the need to achieve a negative overjet through incisor decompensation often leads the orthodontist to extract the upper first premolars. This report illustrates an orthodontic preparation case where due to specific factors inherent in the patient's psychological makeup retroclination of the upper incisors and proclination of the mandibular incisors was achieved without removing any teeth.