No_intervention: Usual treatment - Control group

The patient is referred to his treating dentist with a diagnosis report of his oral state including his periodontal status.~The usual care usually includes the extraction of non-preservable teeth, the dental prosthesis to replace them and at least one descaling session.

Experimental: Periodontal treatment - Intervention group

Periodontal treatment can last up to 6 months depending on the periodontal state, followed by a follow-up period of at least 6 months including a visit at M9.~Briefly, the intervention group includes initial therapy with information on oral hygiene techniques, scaling and surfacing of dental roots. This initial therapy is followed by a resumption of periodontal clinical measures after 6 weeks. Depending on the degree of improvement of the measurements, the treatment is either completed, or continues with further scaling-surfacing and / or performing one or more periodontal surgeries. Periodontal monitoring period often called maintenance includes repeated sessions of simple scaling whose rate does not exceed 4 per year.