title: Aspartate aminotransferase activity in gingival crevicular fluid during orthodontic treatment. A controlled short-term longitudinal study.
abstract: BACKGROUND
  During orthodontic tooth movement, the early response of periodontal tissues to mechanical stress involves an acute inflammatory response, with a sequence characterized by periods of activation, resorption, reversal, and formation in both tension and compression sites. This study used a longitudinal design to examine aspartate aminotransferase (AST) activity in gingival crevicular fluid (GCF) in order to assess whether AST in GCF has potential as a possible diagnostic aid to monitor tooth movement and tissue response during orthodontic treatment.
  
  
  METHODS
  Eighteen patients (mean age, 16.1 years) participated in the study. An upper first molar from each patient undergoing treatment for distal movement served as the test tooth (TT), with its contralateral (CC) and antagonist (AC) first molars used as controls. The CC was included in the orthodontic appliance, but was not subjected to the orthodontic force; the AC was free from any orthodontic appliance. The GCF around the experimental teeth was collected from both mesial and distal tooth sites immediately before appliance activation, 1 hour after, and weekly over the following 4 weeks. Clinical gingival condition was evaluated at baseline and at the end of the experimental period. AST activity was determined spectrophotometrically at 30 degrees C, and the results were expressed as total AST activity (mU/sample).
  
  
  RESULTS
  Throughout the experiment, AST levels were significantly elevated in all sites from the TT and CC groups compared to the AC group where, conversely, AST activity remained at the baseline level. However, enzyme levels in the TT group were significantly greater than in the CCs at tension sites on day 14, and in compression sites on days 7 and 14. Moreover, AST activity from the TT group was significantly greater in compression sites than in tension sites on day 7; this was not observed for the CCs.
  
  
  CONCLUSIONS
  Our results suggest that AST levels in GCF reflect the biological activity which occurs in the periodontium during controlled occlusal trauma and, therefore, should be further evaluated as a diagnostic tool for monitoring correct orthodontic tooth movement in clinical practice.
authors.affiliation: Unit of Biochemistry, Department of Oral Sciences, Dental School, University G. D'Annunzio, Chieti, Italy. giuseppe.perinetti@tin.it
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Perinetti
authors.forename: Michele
authors.initials: M
authors.lastname: Paolantonio
authors.forename: Michele
authors.initials: M
authors.lastname: D'Attilio
authors.forename: Domenico
authors.initials: D
authors.lastname: D'Archivio
authors.forename: Marco
authors.initials: M
authors.lastname: Dolci
authors.forename: Beatrice
authors.initials: B
authors.lastname: Femminella
authors.forename: Felice
authors.initials: F
authors.lastname: Festa
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Spoto
mesh_terms: D000293:Adolescent; D000328:Adult; D001219:Aspartate Aminotransferases / Q000378:metabolism*; D016723:Bone Remodeling / Q000502:physiology; D002648:Child; D019245:Compressive Strength; D003769:Dental Occlusion, Traumatic / Q000201:enzymology*; D003799:Dental Stress Analysis; D005260:Female; D005883:Gingival Crevicular Fluid / Q000201:enzymology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008963:Molar; D016910:Orthodontic Brackets; D010512:Periodontal Index; D018709:Statistics, Nonparametric; D013718:Tensile Strength; D014087:Tooth Movement Techniques / Q000295:instrumentation
chemical_list: D001219:Aspartate Aminotransferases