What's the noun for periodontopathogens? Here's the word you're looking for.
periodontics
(dentistry) The study of supporting structures of teeth—gums, alveolar bone, cementum, and the periodontal ligament—and diseases and conditions that affect them.
“Basic services such as fillings, oral surgery, periodontics and endodontics would be 70 per cent covered.”
“Dental surgery, dental prostheses, periodontics and orthodontic treatment, with the exception of dental treatment as per our definition.”
“Stating this here today, he said it would be started in the area of oral surgery, orthodontics, prosthodontics, and periodontics and conservation dentistry.”