Table 1.

Biomarkers employed in studies on smoking and periodontal disease

Target of qualification	Biomarkers	Specimens
Host responses
Microcirculatory system	Microcirculatory functions and intercellular adhesion molecule	Gingival microvasculature
Host immune inflammatory response systems	Immune cells and immunoglobulins	Blood serum, saliva, gingival crevicular fluid, and gingival tissue
Connective tissue and bone metabolism	Cytokines, prostanoids, and matrix metalloproteinase
Genetic factors	Genotypes associated with the immune system, inflammation, and tissue metabolism	Blood, buccal swabs, and saliva