Calprotectin is a protein complex expressed in neutrophil granulocytes (PMN), monocytes/macrophages and keratinocytes and is considered as a biomarker for acute inflammation. Antimicrobial properties against periodontal and other bacteria have been shown in vitro. Calprotectin levels in GCF correspond with clinical and other biochemical markers of periodontal inflammation as well as with clinical treatment outcome. PMN are supposed to be the main source of calprotectin in GCF, but evidence is still lacking.

Objectives:

Interrelations between GCF-levels of calprotectin and myeloperoxidase (MPO) as an established marker for PMN were longitudinally evaluated.

Methods:

23 patients with generalized aggressive periodontitis were treated by scaling/root planing and adjunctive antimicrobial medications. GCF-samples were collected at baseline and three months after therapy at the patient's initially deepest site. For sampling, a PerioCol collection paper strip (Oraflow, USA) was inserted into the sulcus for 10s, the crevicular fluid flow rate (CFFR) was measured with a Periotron 6000 (Oraflow, USA). Subsequently, clinical parameters PD, CAL, BoP, Pus were recorded with a pressure-sensitive electronic periodontal probe (Florida Probe, USA). Concentrations of calprotectin and MPO were determined by ELISA (BMA, Switzerland; Immundiagnostik, Germany).

Results:

	PD (mm)	BoP (%)	CFFR (µl)	Calprotectin (µg/µl)	MPO (µg/µl)
Baseline	8.1±0.9	91±29	0.50±0.21	34.5±28.8	1.1±1.6
3 Months	4.1±1.4	26±45	0.29±0.14	17±14.1	0.4±0.3
p	<0.001	<0.001	<0.001	0.006	0.002

(Wilcoxon signed rank test)

Calprotectin/MPO

(Baseline)

Calprotectin/MPO

(3 Months)

ΔCalprotectin/ΔMPO

Correlation

(Pearson)

0.714

0.540

0.716

p

<0.001

0.008

0.001