title: Myeloperoxidase enzymatic activity is increased in patients with different levels of dental crowding after initial orthodontic activation.
abstract: BACKGROUND
  Orthodontic tooth movement implies application of forces that generate an inflammatory process. The myeloperoxidase (MPO) enzyme is found inside neutrophil granules. MPO activity indirectly reflects the level of inflammation. The aim of this study was to measure MPO activity in gingival crevicular fluid (GCF) and whole saliva in orthodontic patients with different levels of dental crowding at the alignment phase of orthodontic treatment with the same archwires.
  
  
  METHODS
  Twenty patients were classified according to the irregularity index into 2 groups: severe and minimum crowding (10 in each group). MPO activity was evaluated in GCF and saliva at 0 and 2 hours, and 7 and 14 days after the orthodontic appliances were activated. MPO activity was measured using the modified Bradley-Bozeman technique.
  
  
  RESULTS
  In both groups, the maximum activity was at 2 hours (P <0.05) after activation. MPO activity remained elevated until day 7, and values similar to baseline were found at day 14 in the GCF and saliva samples. Enzymatic activity did not show statistical differences between the groups.
  
  
  CONCLUSIONS
  The amount of dental crowding does not seem to influence MPO activity, which showed similar patterns in GCF and saliva, but the values in GCF reflected the inflammatory changes more accurately than did the values in saliva. The quantification of MPO activity is a useful biologic marker as an indirect measurement of inflammation generated with tooth movement independent of the amount of crowding.
authors: Postgraduate student, Department of Orthodontics, University of Guadalajara, Guadalajara, Jalisco, Mexico.
authors: Alejandra
authors: A
authors: Navarro-Palacios
authors: Professor and chairman, Department of Orthodontics, University of Guadalajara, Guadalajara, Jalisco, Mexico.
authors: Eliezer
authors: E
authors: García-López
authors: Postgraduate student, Department of Molecular Biology and Genomics, Institute of Molecular Biology and Gene Therapy, University of Guadalajara, Guadalajara, Jalisco, Mexico.
authors: Alejandra
authors: A
authors: Meza-Rios
authors: Head, Department of Molecular Biology and Genomics, University of Guadalajara, Guadalajara, Jalisco, Mexico.
authors: Juan
authors: J
authors: Armendariz-Borunda
authors: Professor and researcher, Department of Molecular Biology and Genomics, Institute of Molecular Biology and Gene Therapy, University of Guadalajara, Guadalajara, Jalisco, Mexico. Electronic address: anasol44@hotmail.com.
authors: Ana
authors: A
authors: Sandoval-Rodríguez
mesh_terms: D015415:Biomarkers / Q000032:analysis; D003722:Dental Alloys / Q000737:chemistry; D020724:Elastomers / Q000737:chemistry; D005260:Female; D005500:Follow-Up Studies; D005883:Gingival Crevicular Fluid / Q000201:enzymology*; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000145:classification / Q000628:therapy*; D009532:Nickel / Q000737:chemistry; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D009195:Peroxidase / Q000032:analysis*; D012463:Saliva / Q000201:enzymology*; D012471:Salivary Proteins and Peptides / Q000032:analysis; D014025:Titanium / Q000737:chemistry; D014087:Tooth Movement Techniques / Q000295:instrumentation / Q000379:methods*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D003722:Dental Alloys; D020724:Elastomers; D012471:Salivary Proteins and Peptides; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium; D009195:Peroxidase