Propolis is used by bees to protect their hives. It has been used by humans to boost immunity.
Bees use either wax or propolis to seal cracks in their hives. The larger areas are filled with wax and the smaller with propolis. The color varies depending on the flower source of pollen. Most propolis is dark brown but it can be almost white or yellow. The chemistry, of course, also varies according to the plant source. The texture of propolis is sticky above 68°F but hard and brittle at lower temperatures.
Propolis can be used as a temporary seal on a decayed tooth or post dental procedures such as extraction. It will stick to the gums and teeth for a day or two and some people would regard it as unsightly, but it is an effective antifungal and antimicrobial agent that can be used orally and topically.