title: Tissue response during self-ligating treatment.
abstract: BACKGROUND
  Orthodontic tooth movement is characterized by tissue reactions, which consist in an inflammatory response in periodontal ligament, depending on the forces applied. Self-ligating brackets are able to minimize the sliding resistance and to reduce the forces necessary to move a tooth, with a better tissue response.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the activity of the lactate dehydrogenase (LDH) in gingival crevicular fluid (GCF) during orthodontic tooth movement using self-ligating brackets.
  
  
  METHODS
  Forty patients were selected and treated with two kinds of self-ligating brackets, Quick 2.0 and Smart Clip, and superelastic or thermoactive archwires. Patients' lower arches were bonded and GCF was collected at one side for each tooth at baseline, one hour after bonding and on the 7(th), 28(th) and 42(nd) day. Test teeth were 4.1, 4.3 and 4.5. Control teeth were 1.1, 1.3 and 1.5. Samples were analyzed with a specific assay for LDH activity.
  
  
  RESULTS
  The statistical analysis showed no significant differences in the LDH activity between test and control teeth in the selected groups.
  
  
  CONCLUSIONS
  There are no significant differences, in terms of tissue response, between superelastic and thermoactive archwires.
authors.affiliation: University of Insubria, Department of Orthodontics, Varese, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Bolamperti
authors.forename: Paola
authors.initials: P
authors.lastname: Montanari
authors.forename: Luca
authors.initials: L
authors.lastname: Levrini
authors.forename: Aldo
authors.initials: A
authors.lastname: Macchi
authors.forename: Angelo
authors.initials: A
authors.lastname: Tagliabue
authors.forename: Alberto
authors.initials: A
authors.lastname: Caprioglio
mesh_terms: D000293:Adolescent; D000497:Alloys / Q000737:chemistry; D001641:Bicuspid / Q000201:enzymology; D001696:Biomechanical Phenomena; D002648:Child; D003481:Cuspid / Q000201:enzymology; D003722:Dental Alloys / Q000737:chemistry; D001840:Dental Bonding; D003774:Dental Plaque Index; D012534:Dental Scaling; D004548:Elasticity; D005260:Female; D005500:Follow-Up Studies; D005883:Gingival Crevicular Fluid / Q000201:enzymology*; D006801:Humans; D007180:Incisor / Q000201:enzymology; D007770:L-Lactate Dehydrogenase / Q000032:analysis*; D008297:Male; D009532:Nickel / Q000737:chemistry; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D010512:Periodontal Index; D013499:Surface Properties; D013696:Temperature; D014025:Titanium / Q000737:chemistry; D014087:Tooth Movement Techniques / Q000295:instrumentation*
chemical_list: D000497:Alloys; D003722:Dental Alloys; C040654:titanium nickelide; C013616:nitinol; D009532:Nickel; D014025:Titanium; D007770:L-Lactate Dehydrogenase