As the frequency of dental implants increases, the incidence of complications and peri-implant diseases also increases. Early diagnosis and treatment of the disease is important to prevent consequences up to implant loss. Non-surgical treatment is the recommended treatment in the first stage due to its shorter duration and low morbidity rate. Non-surgical treatment of peri-implantitis provides clinical improvements such as reduced bleeding on probing (20-50%) and, in some cases, reduced pocket depth (≤ 1 mm). This study aims to clinically and radiographically compare two different mechanical treatments in patients with mild and moderate peri-implantitis.

60 patients with at least one implant with mild to moderate peri-implantitis, defined as 2-4 mm radiographic reduced bone level, bleeding index (BI) ≥ 2, and probing pocket depth (PPD) ≥ 4 mm will be randomly allocated to test and control groups, receiving titanium curettes or ultrasonic Carbon tips debridement, respectively. Treatment was performed at baseline. Plaque index (PI), gingival index (GI), Periodontal pocket depth (PD), Bleeding on probing (BOP) gingival recession (GR) and Clinical attachment level (CAL) will be measured at four sites per implant and recorded by examiner at baseline, one, three, six and twelve months. Pus will be recorded as present/not present. The radiographic marginal bone level changes will be calculated at baseline, third months, sixth months and 12 months.

Inclusion criteria:

1. Adult patients (≥18 years old)
2. Systemically healthy (ASA class 1 and ASA class 2)
3. Full-mouth plaque scores ≤20%
4. Implant had been in function for more than 6 months
5. Absence of plaque around the implant
6. Consent to complete all follow-up visits

Exclusion criteria:

1. Mobile implant
2. Overhanging restorations that prevent access to the implant for clinical measurements
3. Unresolvable technical complications that can cause peri-implantitis
4. Presence of active periodontal disease
5. Implants with a history of peri-implantitis treated using graft materials
6. Use of drugs that cause gingival hyperplasia
7. Systemic antibiotic use in the last 3 months
8. Acute and chronic medical conditions that prevent the patient from participating in the study
9. Presence of uncontrolled severe peri-implantitis from neighbouring implants
10. History of radiotherapy in the head and neck region
11. Receiving acute chemotherapy
12. Current corticosteroid therapy

For Outcomes Assessor Masking, Groups were not defined and anonymized and assessor will be blind.