Pyorrehoa is a disease of gums whereas plaque is white to yellow film like deposit seen on tooth surface which subsequently transformed into calculus and new plaque biofilm formed around it ..They causes Pyorrehoa in which infected bleeding gums are seen.

Thank you for your query. Dental plaque is a biofilm which forms on the surface of your teeth.It is formed within few hours after brushing.It is initially colourless but if not removed by proper brushing,it matures into a hard yellow or brownish deposits called calculus.Pyorrhea on the other hand is a disease of the gums.Plaque and calculus causes pyorrhea.In pyorrhea there is redness,swelling and bleeding from gums.Over a period of time teeth becomes loose.It is advisable to get professional cleaning at a dental clinic to prevent build up of plaque and calculus. Regards Dr Shashank Bhatia