Table 4.

Correlations between site-specific clinical measurements, microbiological findings and relative tissue triggering receptor expressed on myeloid cells 1 (TREM-1) mRNA expression

Measurements	Spearman's rho correlation coefficient (n = 45)
PD (mm)	0·273 (P = 0·069)
CAL (mm)	0·179 (P = 0·239)
PI	0·229 (P = 0·130)
BOP	0·363* (P = 0·014)
Porphyromonas gingivalis	0·495** (P = 0·001)
Treponema denticola	0·471** (P = 0·001)
Tannerella forsythia	0·438** (P = 0·003)
Aggregatibacter actinomycetemcomitans	0·206 (P = 0·174)

Significance of correlation, ^*P < 0·05; ^**P < 0·005. PD = pocket depth; CAL = clinical attachment loss; PI = plaque index; BOP = bleeding on probing.