This study is an open-label split-mouth study in which periodontal patients will be treated in order to obtain periodontal health. After non-surgical therapy and air-perio polishing, a periodontal in-situ gelling product (Biorepair Implant Bioactive gel) will be applied in periodontal pockets in two quadrants (Q1-Q3 or Q2-Q4) of the mouth of the participants. At the same time, pockets of the contralateral quadrant will be irrigated with chlorhexidine gel 1%. Patients will continue to use gels at home for the following 14 days and on the same quadrants. Professional ora hygiene session will be performed after 1, 3 and 6 months from the baseline.

Patients are divided into two groups with inverted quadrants administration in order to evaluate the improvements of periodontal inflammation indices and to assess the efficacy of Biorepair Implant Bioactive gel compared to chlorhexidine 1% gel treatment.

This study is an open-label split-mouth study that aims to assess the improvement of periodontal inflammatory indices after sessions of professional oral hygiene with the administration of Biorepair Implant Bioactive Gel and Chlorhexidine gel 1%. It will also compare the efficacy of the two gel in rebalancing periodontal health.

Periodontal patients that will give the informed consent to the treatment protocol and that satisfy the eligibility criteria will undergo 4 sessions of professional oral hygiene. For each session, periodontal inflammatory indices will be recorded and professional manual and mechanical removal of supragingival and subgingival deposits of both arches will be performed, following air-perio polishing with glycine powders. At this stage, patients will be randomized and allocated to the following two groups:

• Group 1: application in periodontal pockets of quadrants Q1 and Q3 of Biorepair Implant Bioactive Gel; irrigation of periodontal pockets of quadrants Q2 and Q4 with chlorhexidine 1% gel.
• Group 2: irrigation of periodontal pockets of quadrants Q1 and Q3 with chlorhexidine 1% gel; application in periodontal pockets of quadrants Q2 and Q4 of Biorepair Implant Bioactive Gel.

Patients will continue with a home oral care protocol, using both gels for the same quadrants of their group for the following 14 days after the professional oral hygiene session.

The first session is at the baseline (T0), the second is after 1 month (T1), the third is after 3 months (T2) and the last is after 6 months (T4).

Inclusion Criteria:

1. Presence of periodontal disease according to the recent 2017 classification (2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions):

   1.1 Severity from grade I onwards (grade I: clinical attachment loss of 1-2 mm, bone loss in the cervical third greater than 15%, no elements loss for periodontitis);

   1.2. Complexity from grade II onwards (grade II: maximum probing depth of 5 mm, bone loss mainly horizontally);

2. Presence of bilateral periodontal probes, both to the right and to the left of the midline incisal line.

3. Subjects who gave their written informed consent to take part of the study.

Exclusion Criteria:

• Patient with cardiac pacemaker
• Patients suffering from psychological, neurological or psychiatric disorders
• Pregnant or breastfeeding women
• Cancer patients undergoing therapy
• Patients taking bisphosphonates within the last 12 months
• Patients with low compliance or inconsistent motivation
• Drug or alcohol users
• Presence of periodontal probes exclusively on the right or left side compared to the midline incisal line

Data will be available upon motivated request to Principal Investigator