title: Correlation between gingival crevicular fluid dipeptidyl peptidase II and IV activity and periodontal attachment loss. A 2-year longitudinal study in chronic periodontitis patients.
abstract: OBJECTIVE
  The aim of this study is to determine whether gingival crevicular fluid (GCF) dipeptidyl peptidase (DPP) II or IV levels, total activity (TA) and concentration (EC), predict progressive attachment loss (AL).
  
  
  METHODS
  Seventy five patients with moderate periodontitis were recruited. GCF was first collected from 16 molar and premolar mesiobuccal sites and then probing attachment level (PAL) and probing pocket depth (PPD) were measured with an electronic probe. Finally, gingival index, gingival bleeding and plaque indices were scored. Patients were given basic periodontal treatment prior to baseline after which the above procedures were repeated. Patients were seen 3 monthly for 2 years and the procedures were repeated. Carefully localised radiographs were taken of the test teeth annually.
  
  
  RESULTS
  One hundred and twenty AL sites, 88 rapid AL (RAL) and 32 gradual AL (GrAL), in 48 patients were detected. DPP II and IV levels (TA and EC) at RAL sites were significantly higher (P < or = 0.0001) than paired control sites at the attachment loss time (ALT) and prediction time (PT). Mean levels over the study period of both proteases (TA and EC) at GrAL sites were significantly higher (P < or = 0.0001) than other paired control sites. The GCF levels of DPP IV were always slightly higher than those of DPP II. Critical values (CV) of 5 microU per 30 s (TA) and 25 microU microL(-1) (EC) for both proteases showed high sensitivity and specificity values for TA and EC and these were the same at both ALT and PT. The positive predictive values were slightly higher for DPP II. Mean site DPP II and IV levels (TA and EC) in intra-patient comparisons were significantly higher (P < or = 0.0001) at RAL and GrAL sites than non-attachment loss (NAL) sites in AL patients and mean patient levels were significantly higher (P < or = 0.0001) in AL patients than NAL patients in inter-patient comparisons.
  
  
  CONCLUSIONS
  These results indicate that both GCF DPP II and IV may be predictors of periodontal attachment loss.
authors.affiliation: Periodontal Department, King's College School of Medicine and Dentistry, London, UK.
authors.forename: B M
authors.initials: BM
authors.lastname: Eley
authors.forename: S W
authors.initials: SW
authors.lastname: Cox
mesh_terms: D000328:Adult; D002908:Chronic Disease; D003774:Dental Plaque Index; D018819:Dipeptidyl Peptidase 4 / Q000032:analysis*; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000032:analysis* / Q000378:metabolism; D018450:Disease Progression; D005260:Female; D005883:Gingival Crevicular Fluid / Q000201:enzymology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D017622:Periodontal Attachment Loss / Q000175:diagnosis / Q000201:enzymology* / Q000276:immunology; D010512:Periodontal Index; D010518:Periodontitis / Q000201:enzymology* / Q000276:immunology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity
chemical_list: D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; C100151:dipeptidyl peptidase II; D018819:Dipeptidyl Peptidase 4