Research Question:

Can a minimally invasive, non-surgical treatment approach (MINST) be more effective than the current standard non-surgical method in treating peri-implantitis, a common inflammatory condition affecting dental implants?

Background:

Dental implants are widely used to replace missing teeth. While they are usually successful, some patients develop a condition called peri-implantitis, an infection that causes inflammation and bone loss around the implant. This can eventually lead to implant failure if not treated properly. Currently, non-surgical treatments are used to clean the area and reduce inflammation. However, these methods often fall short of fully resolving the issue, and many patients require further treatment or even surgery.

A newer approach called MINST (Minimally-Invasive Non-Surgical Therapy) has shown promising results for treating gum disease around natural teeth. This method focuses on precision cleaning with minimal trauma to the surrounding tissues, reducing pain and improving healing. While MINST works well for gum disease, its effectiveness for treating peri-implantitis has not yet been tested.

Purpose of the Study:

This clinical trial will compare the effectiveness of MINST with the standard non-surgical treatment currently used for peri-implantitis.

The aim is to determine whether MINST can better treat the disease, improve healing, and reduce discomfort for patients.

Hypotheses:

Alternate Hypothesis (What we expect to find): MINST will result in better outcomes, specifically, fewer deep pockets around the implant, less bleeding, and fewer signs of infection, compared to the standard treatment.

Null Hypothesis: There will be no significant difference between the outcomes of the two treatment approaches.

Study Design:

Type of Study: A randomized controlled trial (RCT) involving 106 patients. Duration: Patients will be followed for 12 months after treatment. Locations: Multiple dental centers participating in the trial. Method: Half of the participants will receive MINST; the other half will receive the standard treatment. Neither patients nor outcome assessors will know which treatment was used (single-masked). What Will Be Measured? Primary Goal: To see how many patients show healing (defined as smaller pockets, little or no bleeding, and no pus) 12 months after treatment.

Secondary Goals:

Patient-reported outcomes, including pain levels and quality of life Changes in pocket depth and tissue attachment Bacterial changes Time taken for treatment appointments Why Is This Important? If MINST proves to be more effective and comfortable for patients, it could change how peri-implantitis is managed in the future- potentially reducing the need for surgery, improving patient experience, and helping more people keep their dental implants for longer.

Study Overview (Design) This is a research study being carried out at several dental clinics to test two different types of non-surgical treatments for periimplantitis- a condition where the tissues around a dental implant become infected and inflamed. The goal is to see which treatment works better over a period of 12 months. Study Schedule Participants will be followed for 1 year after their treatment, with several check-up visits to monitor progress and collect information.

Who Can Take Part? Inclusion (Who can join?) People with peri-implantitis, a condition affecting the gums and bone around a dental implant.

At least one area around the implant with deep pockets (>6mm) and some bone loss.

Page 8 of 23 Project ID: 51376 Implants must be accessible for cleaning without removing the crown or prosthetic.

Good general mouth hygiene (low plaque and bleeding scores). Exclusion (Who cannot join?) People who recently took antibiotics. Pregnant or breastfeeding women. Those with certain medical conditions (e.g., uncontrolled diabetes). People who already had treatment for this condition recently. Smokers or people who vape. Implants that are severely damaged or considered untreatable. Recruiting Patients Patients referred to specialist periodontal clinics will be checked to see if they qualify. If they do, they'll be informed about the study and can decide whether to participate. If they agree, they will attend a baseline appointment where their current oral health will be recorded. Randomisation (Choosing Treatment Groups)

Participants will be randomly assigned to one of two treatment groups:

Standard non-surgical treatment Minimally invasive non-surgical treatment (MINST) The method of choosing who goes into which group is like flipping a coin-but controlled by a secure computer system to ensure fairness. Blinding/Masking (Avoiding Bias) The dentist doing the treatment will know which method is being used (they have to, to apply the treatment correctly).

But the person who checks the results (examiner) and the person analyzing the data (statistician) won't know who received which treatment. This helps make the study results more reliable. Patients will know which treatment they received. Treatment and Follow-up Visits

Participants will attend up to 7 visits over 12 months:

Visit 1 (Day 0 - Baseline) Consent to take part Full dental and medical check Photos taken Oral hygiene advice Visit 2 (Treatment)

One of the two types of cleaning will be performed:

Standard: Cleaning using ultrasonic tools and curettes. MINST: Cleaning using finer tools and magnification for a more gentle and precise approach.

Visit 3 (1 Month) Follow-up with oral hygiene support Check for pain or discomfort Short cleaning if needed Visit 4 (3 Months) - Optional Check-up with hygiene instructions Visit 5 (6 Months) Page 9 of 23 Project ID: 51376 Full periodontal check Cleaning and photos Visit 6 (9 Months) - Optional Same as 6-month visit Visit 7 (12 Months) Final check-up with full periodontal exam and photos Study completed Rescue Treatment (If Needed)

If the implant doesn't improve or worsens during the study, the patient may receive additional treatment, which could include:

Extra cleaning Surgery In serious cases, implant removal These situations will be documented and analyzed. Clinical Measurements

At various visits, the study team will:

Measure gum pocket depths around teeth and implants. Record bleeding, gum recession, plaque, and other oral health signs. Use a standard dental probe for measurements at six points around each implant and tooth.

Photographs Photos and sometimes videos will be taken to monitor changes over time. These will be stored securely and anonymised to protect patient privacy. PROMs (Patient-Reported Outcomes) Patients will fill in questionnaires at several time points (baseline, 4, 8, and 12 months) to report how their mouth condition affects their daily life. One is a general oral health quality-of-life questionnaire (OHIP-14), and another is implant-specific.

Repeatability (Calibration) To make sure the measurements are accurate and consistent, all examiners will go through training and calibration exercises before the study starts. X-rays Previous X-rays (taken within the last 3 months) will be used to confirm the bone loss around the implant. No new X-rays will be taken solely for the study. End of Study The study ends one year after the last patient finishes their follow-up. After that, patients can choose to be monitored annually for up to 4 more years.

Inclusion Criteria:

• Diagnosis of peri-implantitis (any implant surface/any amount of keratinized gingiva)
• PPD>6mm at least in one implant surface
• Bone levels ≥3mm apical of the most coronal portion of the intra-osseous part of the implant.
• Implant surface deemed accessible by the treating clinician, without the need to remove the prosthetic suprastructure
• Full-mouth plaque score <30%
• Full-mouth bleeding score <30%

Exclusion Criteria:

• A course of antibiotics within the past 3 months
• Pregnant/lactating women
• Relevant medical history as evaluated by the examining clinician which may have the potential to affect periodontal surgical treatment (e.g., uncontrolled diabetes HbA1c≥7).
• Individuals on long-standing (2 or above years) supportive peri-implant care (SPIC)
• Previous non-surgical or surgical therapy of the affected implant within 12 months
• Current smoking or vaping (defined as any smoking or vaping within 12 months)
• Implant considered hopeless according to the treating clinician (e.g. mobility, circumferential bone loss >80%, implant outside the bone envelope)
• Case needing adjunctive antibiotic therapy, according to the treating clinician

upon requested to the authors

Randomisation lists for each centre will be generated by an independent researcher, who will be involved in the study. The examiners, who assess the clinical variables, will be blinded with regards to the patients' treatment assignments. The measures will include no access to the dental records as to which treatment has been assigned and no access to the patients' treatment file.

The statistician who will perform the statistical analyses, will have no access to the allocation of the patients into the respective treatment group.

The clinician cannot be blinded since she/he has to handle the different devices, but she/he will have no access to the data collection sheets or the group allocation. The assistant to the clinician cannot be blinded since she/he has to handle the different devices, but she/he will have no access to the data collection sheets or the group allocation. The patients will be not blinded to the treatment provided.