title: An investigation into the mechanical and aesthetic properties of new generation coated nickel-titanium wires in the as-received state and after clinical use.
abstract: OBJECTIVE
  The purpose of this study was to compare the mechanical, structural, and aesthetic properties of two types of aesthetic coated nickel-titanium (NiTi) wires compared with comparable regular NiTi wires in the as-received state and after clinical use.
  
  
  METHODS
  Sixty one subjects were randomly assigned to four groups (N = 61), two groups of coated wires and two groups of comparable, non-coated controls (n = 15/group). The period in the mouth ranged from 4 to 12 weeks after insertion. In total, 121 wires (61 retrieved and 60 as-received) were used in the study. The percentages of coating retention and loss were extrapolated from scans. A brief survey of five questions with three choices was given to all patients. Differential scanning calorimetry (DSC) and three-point bending tests were done on as-received and used wires.
  
  
  RESULTS
  The surface characterization by the percentage of resin remaining indicated that most wires in both test groups lost a significant amount of coating. A patient survey indicated that this was a noticeable feature for patients. DSC analysis of the wires indicated that the metallurgical properties of the coated wires were not similar to the uncoated wires in the as-received condition. Three-point bending results indicate a wide variation in test results with large standard deviations among all the groups.
  
  
  CONCLUSIONS
  The extent of coating loss requires investigating, as do the biological properties of the detached coating.
  
  
  CONCLUSIONS
  Both wires lost a significant amount of aesthetic coating after varying periods in the mouth. The metallurgical testing of these findings may indicate that these wires perform differently in the mouth.
authors.affiliation: *Department of Developmental Sciences, Marquette University School of Dentistry, Milwaukee, WI, USA, thomas.bradley@marquette.edu.
authors.forename: T Gerard
authors.initials: TG
authors.lastname: Bradley
authors.affiliation: *Department of Developmental Sciences, Marquette University School of Dentistry, Milwaukee, WI, USA.
authors.forename: David W
authors.initials: DW
authors.lastname: Berzins
authors.affiliation: *Department of Developmental Sciences, Marquette University School of Dentistry, Milwaukee, WI, USA.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Valeri
authors.affiliation: **Division of Biostatistics, Medical College of Wisconsin, Milwaukee, USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Pruszynski
authors.affiliation: ***Department of Orthodontics and Paediatric Dentistry, Center of Dental Medicine, University of Zurich, Switzerland.
authors.forename: Theodore
authors.initials: T
authors.lastname: Eliades
authors.affiliation: ****Department of Orthodontics and Dentofacial Orthopedics, Medical School, University of Bern, Switzerland.
authors.forename: Christos
authors.initials: C
authors.lastname: Katsaros
mesh_terms: D000293:Adolescent; D002152:Calorimetry, Differential Scanning / Q000379:methods; D002648:Child; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D003722:Dental Alloys / Q000737:chemistry; D004548:Elasticity; D004868:Equipment Failure; D004955:Esthetics, Dental; D005260:Female; D006801:Humans; D008297:Male; D008422:Materials Testing / Q000379:methods; D009532:Nickel; D016382:Orthodontic Appliance Design; D009969:Orthodontic Wires; D018583:Pliability; D014025:Titanium; D055815:Young Adult
chemical_list: D020099:Coated Materials, Biocompatible; D003722:Dental Alloys; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium