Page "Cigarette" Paragraph 20

The paper for holding the tobacco blend may vary in porosity to allow ventilation of the burning ember or contain materials that control the burning rate of the cigarette and stability of the produced ash.

The papers used in tipping the cigarette ( forming the mouthpiece ) and surrounding the filter stabilize the mouthpiece from saliva and moderate the burning of the cigarette as well as the delivery of smoke with the presence of one or two rows of small laser-drilled air holes.