Two groups are aimed at being investigated in three centers (CICOM, Clinica Branemark and Clinica Joan Pi)

• Test group: Group electrolytic approach (EA): Mechanical detoxification using curettes + NiTi brushes + EA (GalvoSurge) during 2 minutes
• Control group: Group hydrogen peroxide (HP): Mechanical detoxification using curettes + NiTi brushes + hydrogen peroxide 5% for 2 minutes soaked in a gauze Patients´ group selection will be randomly allocated. For patients whom their personal clinical record # ends in a number from 0 to 4 will be included in the test group, while for patients whom their personal clinical record # ends from 5-9 will be included in the control group.

The infra-osseous component will be regenerated using xenograft (Creos, NB) + autogenous bone in a ratio 1:1 harvested from the adjacent area. A resorbable membrane (Creos, NB) will be placed to compartmentalize the infra-osseous component following a poncho-like approach.

Inclusion:

• Screw-retained or cement-retained fixed or removable implant-supported prosthesis for a minimum of 36 months.
• All patients in age of 18 to 80
• non-smokers
• no presence of systemic disease or medication known to alter bone metabolism
• partial or complete edentulous patients that have no active periodontal disease.

Exclusion criteria:

• pregnancy or lactation
• history of or current smokers
• uncontrolled medical conditions,
• lacking keratinized mucosa (≤2mm) on the lingual or buccal implant sites,
• advanced(A) peri-implantitis (>50% of the implant length).