Table 1.

The expression of MMP-9 in different oral tissues.

Tissue types	Cases	Expression of MMP-9		Positive rate %	χ²	P
Tissue types	Cases	Positive	Negative	Positive rate %	χ²	P
Normal mucosa	10	3	7	30.00	5.203	<0.05
OSCC	42	29	13	69.05	5.203	<0.05