Crown Removal in Non-Surgical Peri-Implantitis Therapy: A Randomized Trial

NCT07391202 | Not Yet Recruiting

• 1 other identifier: 29012026
• Study Type: interventional
• Target: 36
• Locations: 0 countries
• Sites: N/A

Brief Summary

The aim of this single-blind, randomized controlled clinical trial is to evaluate whether removal of the prosthetic crown influences the clinical effectiveness of non-surgical mechanical therapy in implants affected by peri-implantitis. The study is designed to compare changes in several clinical and radiographic parameters between baseline and follow-up examinations at 3, 6, and 12 months. The primary outcome measure will be the mean peri-implant probing depth (PIPD). Secondary outcomes will include changes in gingival recession (REC), radiographic marginal bone level (MBL), modified bleeding index (mBI), and additional patient-related variables.

Conditions

Peri-implantitis

Outcome Measures

Primary Outcomes (1)

• Peri-implant probing depth (PIPD)

  Change in mean peri-implant probing depth (PIPD) at the implant level (measured at 6 sites per implant) from baseline to 3, 6, and 12 months after crown removal.

  From enrollment to the end of treatment at 1 year

Study Arms (2)

Non-surgical therapy with prosthetic crown removal

EXPERIMENTAL

Implants allocated to this group will receive non-surgical peri-implant therapy after temporary removal of the prosthetic crown. The crown will be unscrewed before treatment to allow direct access and full visibility of the implant surface and peri-implant tissues. Mechanical debridement will then be performed under local anesthesia using sonic and ultrasonic devices with dedicated thin tips and Gracey curettes, according to the EFP S3-level clinical practice guidelines. After completion of debridement and biofilm removal, the prosthetic crown will be reinstalled. Patients will receive oral hygiene instructions and reinforcement.

Procedure: Non-Surgical Peri-Implant Therapy without Crown

Non-surgical therapy without prosthetic crown removal

ACTIVE COMPARATOR

Implants allocated to this group will receive non-surgical peri-implant therapy with the prosthetic crown left in place. Mechanical debridement will be performed under local anesthesia using the same instruments and protocol as in the test group (sonic scaler, ultrasonic devices, and Gracey curettes), but with access limited by the presence of the restoration. Professional oral hygiene instructions and reinforcement will also be provided.

Procedure: Non-Surgical Peri-Implant Therapy with Crown

Interventions

Non-Surgical Peri-Implant Therapy without Crown PROCEDURE

In this group, the prosthetic crown will be temporarily removed before treatment to allow direct and complete access to the peri-implant tissues and implant surface. After local anesthesia, a thorough mechanical debridement will be performed up to the bottom of the peri-implant pocket using sonic scalers, piezoelectric/ultrasonic devices with dedicated thin tips, and Gracey curettes. The absence of the crown enables improved visualization, more effective instrumentation, and more accurate disruption of the submucosal biofilm. At the end of the procedure, the prosthetic crown will be repositioned. Standardized oral hygiene instructions and motivation will be provided. This intervention aims to maximize cleaning efficacy by eliminating prosthetic-related access limitations.

Non-surgical therapy with prosthetic crown removal

Non-Surgical Peri-Implant Therapy with Crown PROCEDURE

In this group, non-surgical mechanical therapy will be carried out with the prosthetic crown left in place. After local anesthesia, debridement of the peri-implant pocket will be performed using the same instruments and protocol as in the test group, including sonic scalers, ultrasonic devices with thin tips, and Gracey curettes. The presence of the crown limits access to some peri-implant areas and reflects routine clinical practice. Patients will receive standardized oral hygiene instructions and reinforcement. This intervention represents the conventional non-surgical management of peri-implantitis without removal of the restoration

Non-surgical therapy without prosthetic crown removal

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients with at least one implant diagnosed with peri-implantitis (Berglundh et al., 2018);
• Patients with a crown on the implant affected by peri-implantitis that is removable;
• Patients who have not received non-surgical peri-implant therapy in the previous 6 months;
• Patients who have not taken systemic antibiotic therapy in the previous 3 months.

You may not qualify if:

• Full-Mouth Plaque Score (FMPS) \> 30% at the time of non-surgical therapy;
• Pregnant or breastfeeding women;
• Relevant medical history, in the opinion of the examining clinician, that could affect the outcome of non-surgical peri-implant therapy;
• Smoking patients consuming \> 10 cigarettes/day.

Sponsors & Collaborators

• G. d'Annunzio University: lead

MeSH Terms

Conditions

Peri-Implantitis

Interventions

Crowns

Condition Hierarchy (Ancestors)

Periodontal Diseases; Mouth Diseases; Stomatognathic Diseases

Intervention Hierarchy (Ancestors)

Dental Prosthesis; Prosthodontics; Dentistry; Prostheses and Implants; Equipment and Supplies

Central Study Contacts

Michele Paolantonio, DDS, MD

CONTACT

+3908713554158; michelapolantonio@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Full Professor

Study Record Dates

• First Submitted: January 29, 2026
• First Posted: February 5, 2026
• Study Start: April 1, 2026
• Primary Completion (Estimated): July 31, 2027
• Study Completion (Estimated): July 31, 2027
• Last Updated: February 5, 2026

Record last verified: 2026-01