Seventy patients will be previously treated for moderate-to-severe periodontitis according to their individual needs. Thirty days after completion of periodontal treatment, these patients will be randomized to one of the following groups of periodic preventive maintenance (PPM): G1 - performed only control supragingival; G2 - performed supra and subgingival control (when necessary).

The maintenance consultations will be scheduled every 3 months for 24 months. The hypothesis is that the effect of the supragingival control (conducted over 24 months) will be similar to the effect of the supra- and subgingival control combined, above the restoration and progression of periodontitis.

This randomized clinical trial, single-blind, aims to compare the effect of the supragingival biofilm control with the effect of supra- and subgingival biofilm control, performed by the patient-professional binomial, in periodontal patients treated, above the restoration and progression of periodontitis during the preventive periodic maintenance (PPM). Seventy patients with moderate-to-severe periodontitis, aged from 35 years, will be included. Participants will be periodontally treated according to their needs. After 30 days of the end of treatment, participants will be randomized (stratified for smoking) in two groups: Group 1 (G1)- Supragingival biofilm control; Group 2 (G2)- Supra and subgingival biofilm control. MPP consultation will take place every 3 months, for 24 months, in which the G1 will only receive procedures of supragingival biofilm control, and G2 will receive, beyond the supragingival control, subgingival interventions.

Inclusion Criteria:

• age from 35 years;

• present at least 12 teeth in the mouth;

• patients diagnosed with moderate-to-severe periodontitis according to the criteria of the AAP (1999):

  • to present ≥ 2 interproximal sites with AL ≥ 6 mm AND ≥1 interproximal site with PD ≥ 5 mm; or
  • to present ≥ 2 interproximal sites with AL ≥ 3mm OR ≥ 2 interproximal sites with PD ≥ 5 mm (in different teeth).

Exclusion Criteria:

• presence of systemic conditions unfavorable to periodontal treatment (diabetes, cardiovascular changes with antimicrobial prophylaxis indicated);
• positive history of periodontal treatment and maintenance in the 12 months preceding the study;
• positive history of using anti-inflammatory drugs and antibiotics in the 3 months prior to initial consultation;
• patients in use of fixed orthodontic appliance;
• pregnant patients.