pyorrhoea vs pyorrhea alveolaris

pyorrhoea and pyorrhea alveolaris both are nouns.

Word	Noun	Adjective	Verb	Adverb
pyorrhoea	Yes	No	No	No
pyorrhea alveolaris	Yes	No	No	No

As nouns, pyorrhoea and pyorrhea alveolaris are synonyms defined as:

pyorrhoea and pyorrhea alveolaris: chronic periodontitis; purulent inflammation of the teeth sockets

Other synonyms of pyorrhoea include pyorrhea, Riggs' disease.

pyorrhoea (noun)	pyorrhea alveolaris (noun)
discharge of pus	chronic periodontitis; purulent inflammation of the teeth sockets
chronic periodontitis; purulent inflammation of the teeth sockets