title: The importance of data presentation regarding gingival crevicular fluid myeloperoxidase and elastase-like activity in periodontal disease and health status.
abstract: BACKGROUND
  The enzymatic profile of gingival crevicular fluid (GCF) is being analyzed with increasing interest, but related studies lack a general consensus on most methodological points, including the appropriate mode of data presentation.
  
  
  METHODS
  GCF myeloperoxidase (MPO) and elastase-like activity (ELA) levels were spectrophotometrically determined on a total of 60 subjects who were divided into three equal subgroups as early-onset periodontitis (EOP), adult periodontitis (AP), and healthy. GCF enzyme levels were calculated and evaluated both as total enzyme activity and enzyme concentration. The correlations between these GCF enzymes and clinical periodontal status were also analyzed.
  
  
  RESULTS
  With both modes of data presentation, the results regarding MPO activity were consistent. When presented either as total MPO activity or MPO concentration, the periodontally healthy group showed significantly lower MPO activity than the two patient groups (P<0.05). However, two modes of data presentation did not match when GCF ELA was concerned. When data were reported as total ELA, the healthy group exhibited lower enzyme activity (0.02 +/- 0.001 U) than EOP (0.04 +/- 0.01 U) and AP (0.06 +/- 0.02 U) groups; but when reported as concentration, the highest ELA levels were seen in the healthy group (221 +/- 31.53 nmol/min/ml), followed by AP (98.63 +/- 23.03 nmol/min/ml) and EOP (70.49 +/- 12.02 nmol/min/ml) (P<0.05). A strong-positive and significant correlation existed between GCF MPO and ELA. Correlations with clinical parameters were mostly observed with total activities.
  
  
  CONCLUSIONS
  The findings of the present study confirm the relationship between GCF ELA and MPO activity and periodontal disease and also support the functional relativity between the two enzymes. Furthermore, based on these findings, it can be suggested that data presentation by use of total activity seems to be more sensitive in both the reflection of the actual enzymatic profile of GCF and also the existing clinical periodontal status. For each GCF component, the validity of different modes of data presentation should be considered.
authors.affiliation: Department of Periodontology, Faculty of Dentistry, University of Hacettepe, Ankara, Turkey.
authors.forename: N
authors.initials: N
authors.lastname: Yamalik
authors.forename: F
authors.initials: F
authors.lastname: Cağlayan
authors.forename: K
authors.initials: K
authors.lastname: Kilinç
authors.forename: A
authors.initials: A
authors.lastname: Kilinç
authors.forename: C
authors.initials: C
authors.lastname: Tümer
mesh_terms: D000293:Adolescent; D000328:Adult; D010520:Aggressive Periodontitis / Q000201:enzymology*; D000704:Analysis of Variance; D003625:Data Collection; D005260:Female; D005883:Gingival Crevicular Fluid / Q000201:enzymology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010196:Pancreatic Elastase / Q000032:analysis*; D010512:Periodontal Index; D010518:Periodontitis / Q000201:enzymology*; D010519:Periodontium / Q000201:enzymology*; D009195:Peroxidase / Q000032:analysis*; D015203:Reproducibility of Results; D012107:Research Design; D012680:Sensitivity and Specificity
chemical_list: D009195:Peroxidase; D010196:Pancreatic Elastase