Clinical Research Directory

Adjunctive Keratinized Mucosa Augmentation in Peri-Implantitis

This study aims to increase the width and thickness of peri-implant keratinized mucosa (KM) by transferring a properly dimensioned free gingival graft (FGG) from the palatal donor site and to evaluate its effect as an adjunctive approach to non-surgical peri-implantitis therapy. The procedure is indicated for patients diagnosed with peri-implantitis who present with an inadequate KM (midbuccal KM height \< 2 mm). One month after non-surgical therapy, patients in the test group will undergo keratinized mucosa augmentation using an FGG, while patients in the control group will continue with supportive periodontal therapy and regular follow-up visits. The primary outcome measure of the study is the change in probing depth (PD) at 12 months following peri-implantitis treatment.

Minimally-Invasive Non-Surgical Therapy of Peri-Implantitis

This multicenter, single-masked randomized controlled clinical trial evaluates the effectiveness of minimally-invasive non-surgical therapy (MINST) compared with standard non-surgical peri-implant therapy (NSPT) in patients diagnosed with peri-implantitis. The study investigates clinical outcomes, radiographic bone levels, patient-reported outcomes, and treatment time over 12 months.

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

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.

Long-term Stability of Peri-implantitis Treatments: a 3-year Clinical Evaluation

This prospective study will include patients previously enrolled in the PER-ECL-2019-05 trial who attend the Department of Periodontology (CUO) for maintenance therapy or treatment of periodontal and/or peri-implant diseases, provided they meet the inclusion criteria. Initially, 36 patients with advanced peri-implantitis were enrolled in a randomized clinical trial evaluating the clinical, radiographic and patient-related outcomes of reconstructive therapy following a non-surgical phase of peri-implantitis treatment compared to non-surgical treatment alone (PER-ECL-2019-05) (10). At the study conclusion 34 patients were re-evaluated and 2 patients were excluded from the study (10). In the original study, adult patients presenting at least one titanium implant diagnosed with peri-implantitis were identified among patients referred to the Department of Periodontology of UIC between January 2020 and October 2022. Peri-implantitis was diagnosed following the case definition of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions (11) that is, PPD ≥ 6 mm combined with bleeding on probing (BOP) and/or suppuration (SUP), together with progressive bone loss in relation to the radiographic bone level assessment. In those cases where initial radiograph was unavailable, the definition of a peri-implantitis case was based on radiographic evidence of bone level ≥3 mm apical to the most coronal portion of the intra-osseous part of the implant (12). At the outset of the original study, participants were randomly assigned to one of two groups: The first group received only non-surgical therapy for peri-implantitis, while the second group underwent a non-surgical phase followed by reconstructive surgical treatment. This design allowed for direct comparison of the clinical, radiographic, and patient-centered outcomes between the two treatment modalities. Both groups were managed and evaluated according to standardized protocols, ensuring consistency and reliability of the results at 12 months . Patients who have not returned to the Department will be contacted by telephone and invited to participate through the academic office. At 36 months, a single follow-up will be carried out including: A detailed clinical examination. A standardized radiographic assessment.

Polynucleotide and Hyaluronic Acid-based Gel as Adjunctive Therapy to Non- Surgical Treatment of Intraosseous Peri-implant Defect. A Randomized Clinical Trial

This randomized, placebo-controlled clinical trial evaluates the efficacy of a polynucleotide and hyaluronic acid-based gel (PN-HA) as adjunctive therapy to non-surgical flapless treatment of peri-implantitis. The main goal is to assess probing pocket depth (PPD) reduction after 6 months compared to placebo. Study Design: * Type: Interventional (Clinical Trial) * Allocation: Randomized (computer-generated blocks) * Intervention Model: Parallel assignment * Masking: Single-blind (examiner-blinded) * Primary Purpose: Treatment * Estimated Enrollment: 32 participants * Duration: 6 month follow-up

Peri-implantitis Treatment With Chitosan Brush

In dentistry, dental implant applications for tooth loss/deficiency are prominent and provide successful long-term results in terms of functionality and aesthetics. However, peri-implant diseases such as peri-implant mucositis and peri-implantitis may develop due to biofilm accumulation around the implant. In peri-implantitis, in addition to the clinical inflammation findings seen in peri-implant mucositis, there is also progressive bone loss. This condition is to be treated with non-surgical or surgical methods. Titanium curettes, ultrasonic instruments, laser systems, and chitosan brushes are used for biofilm removal in non-surgical treatment. Chitosan is a natural polysaccharide obtained from chitin. It is biocompatible, biodegradable, and has antibacterial activity. In addition, chitosan reduces the levels of IL-1β, IL-6, and TNF-α, which also play a role in the pathogenesis of peri-implantitis, and exhibits anti-inflammatory effects on macrophages activated by lipopolysaccharide. Although many methods are used to treat peri-implantitis, successful and predictable results cannot be obtained. This study aims to examine the clinical and immunological findings and observe the changes in the non-surgical treatment of peri-implantitis using chitosan brush or titanium curette over 12 months. Sixty dental implants diagnosed with peri-implantitis clinically and radiographically at the Department of Periodontics, Faculty of Dentistry, Hacettepe University will be included in the study. Non-surgical peri-implantitis treatment of these patients will be performed using a chitosan brush (N=30, case group) or titanium curette (N=30, control group). Pre-operative and post-operative 3rd, 6th, and 12th months, clinical periodontal indices will be recorded, peri-implant crevicular fluid (PIF) will be collected, and maintenance treatment will be applied to the patients. IL-1β, TNF-α, IL-8, IL-10, and IL-17 levels in the collected PIF will be determined by the ELISA method. The effectiveness of chitosan brush and titanium curette in treating peri-implantitis will be evaluated and compared clinically and immunologically.

Natural Bioactive Gel for Peri-Implantitis

This study is a randomized controlled clinical trial using a split-mouth design to evaluate the effectiveness of a natural bioactive gel (Sterify Gel®) as an adjunct to standard non-surgical therapy for peri-implantitis. Peri-implantitis is an inflammatory disease that affects the tissues around dental implants and can lead to bone loss and implant failure. The goal of the study is to determine whether the application of Sterify Gel®, which contains polyvinyl polymers, hydroxytyrosol, magnesium ascorbyl phosphate, and nisin, can improve clinical outcomes when used in addition to conventional mechanical debridement and air-polishing. The trial will include 20 patients, each with at least two implants in different quadrants affected by peri-implantitis. One implant will be treated with standard therapy plus the gel (test site), while the other will receive standard therapy alone (control site). Clinical outcomes will be measured over a 9-month period, including plaque levels, bleeding on probing, probing depth, suppuration, and bone loss. The results will help assess whether this gel enhances the effectiveness of routine non-surgical peri-implantitis treatment.

Investigation of Biofilm Formation on Temporary push-on Rings of Implant Crowns

This in-vivo study investigates early (48h), mature (2 weeks) and long-term (3 months) biofilm formation and composition on temporary push-on cones (exchangeable conical rings) made of noble-alloy-based materials (Pagalinor, PA) in comparison to Titanium-6Aluminum-7Niobium alloy (TAN) presently used in the transmucosal portion of dental implant abutments.

Reconstructive Treatment of Peri-implantitis With Combined Defects

The aim of this randomized clinical study is to assess the additional clinical benefit of incorporating a resorbable collagen membrane (CM) alongside a xenogeneic bone graft-specifically, deproteinized bovine bone mineral with 10% collagen (DBBM-C)-in the reconstructive surgical treatment of peri-implantitis involving combined (i.e., contained and non-contained) defect configurations. Accordingly, the study addresses the following research questions: * Does the adjunctive use of a CM in combination with DBBM-C improve treatment success compared to DBBM-C alone in the management of combined peri-implantitis-related defects? * Does the combined use of a CM and DBBM-C lead to superior patient-reported outcomes (PROs) compared to the use of DBBM-C alone in the reconstructive treatment of such defects? A total of 60 patients who have been referred to the Gazi University Department of Periodontology will be randomly assigned to receive test (DBMM-C +CM) or control group (DBMM-C) treatments. Clinical parameters will be assessed at baseline (i.e., prior to surgery), and at the 6-, and 12-month post-operatively. Radiographic examinations will be carried out at baseline and 12 months post-operatively. Patient oral health related to the treatment procedures will be evaluated using a written questionnaire \[Oral Health Impact Profile (OHIP-14)\] prior to treatment and after 2 weeks, 1, and 12 months following surgical therapy. Regarding post-treatment pain and overall patient satisfaction with treatment modalities, responses will be scored on a visual analog scale (VAS, 100 mm).

The Adjunctive Effect of a Titanium Brush in the Non-Surgical Treatment of Peri-Implantitis

Peri-implantitis is a plaque-associated condition occurring around dental implants, characterized by inflammation in the peri-implant mucosa and loss of supporting bone. To stop this progression, mechanical debridement of biofilm and calculus is commonly used to treat peri-implant lesions as well as the use of adjunctive measures such as titanium brushes. As observed, they improved plaque removal when compared with steel curettes alone. Therefore, it is of interest to evaluate the impact of this procedure in terms of clinical, radiographic and microbiological outcomes to assess their efficacy.

20-25 Year Follow-Up on Regenerative Bone Procedures for Peri-Implantitis

The goal of this 20-25-year observational study is to investigate the outcomes of bone regenerative surgery in peri-implantitis. Two different techniques will be compared: surgery with a bone substitute alone and surgery with a bone substitute combined with a membrane, to determine their effectiveness and assess whether one is more effective than the other. The intention of this observational study is to learn more about the long-term effects of bone regenerative surgery in patients with peri-implantitis. Patients will be called in for a clinical and radiographic examination of the surgically treated implant(s). Probing pocket depths, presence of pus, bleeding around the implant (s) and a radiograph of the implant (s). To be able to compare with the 1, 3, 5 and 10 year measurements.

Non-Surgical Treatment of Peri-implantitis with Systemic Azithromycin or Placebo

The primary objective of this study is to evaluate the change in probing depth in patients with peri-implantitis, assessing the influence of systemic antibiotic (azithromycin) adjunctive to non-surgical treatment at 12 months. The secondary objective is to assess clinical, radiographic, microbiological, and systemic changes at 3, 6, and 12 months. This study is designed as a placebo-controlled, randomized, triple-blind clinical trial in subjects diagnosed with peri-implantitis. The treatment will consist of debridement of the implant surface and curettage of the pocket epithelium. The control group will receive placebo (1 placebo tablet per day for 3 days), and the test group will receive systemic azithromycin 500 mg per day for 3 days (1 tablet of 500 mg azithromycin per day for 3 days).

Evaluation of Fractalkine and Its Receptor in Peri-implantitis

In this study, mechanical debridement group, Er:YAG laser group and diode laser group will be compared in terms of reducing peri-implant sulcus depth in the treatment of peri-implantitis.

Transcriptome, Proteome and Microbiome Profile in Periodontal and Peri-implant Diseases

1. To investigate the transcriptomic profile of periodontitis and peri-implantitis. Patients with defined periodontitis, at two non-adjacent teeth and peri-implantitis at ≥ one implant in function of ≥ one year, will be included to investigate the gene expression profile in tissue affected by periodontitis and peri-implantitis. Subjects will undergo a full-mouth examination performed by a calibrated examiner, including assessment of caries, bone abnormalities and infections according to intraoral x-ray, plaque index and pocket probing depth, suppuration, bleeding on probing, alveolar bone loss, and the number of teeth. During surgical intervention, tissue biopsies (two specimens per site) will be collected by a periodontist from site with ongoing periodontitis and site from ongoing peri-implantitis. 2. To study the microbiome and biomarker profile associated with periodontitis and peri- implantitis. Patients with defined periodontitis, at two non-adjacent teeth and peri-implantitis at ≥ one implant in function of ≥ one year, will be included in this study to determine the bacteria composition, cytokine profile and inflammatory biomarkers profile. Subjects will undergo a full-mouth examination performed by a calibrated examiner, including assessment of caries, bone abnormalities and infections according to intraoral x-ray, plaque index and pocket probing depth, suppuration, bleeding on probing, alveolar bone loss, and number of teeth. Peri-implant crevicular fluid (PICF), gingival crevicular fluid (GCF), saliva and submucosal/subgingival plaque will be collected.The presence and composition of periodontal and peri-implant plaque samples are investigated.

Effect of Enamel Matrix Derivative or Hyaluronic Acid on Non-Surgical Treatment of Peri-Implantitis

The aim of the present randomized controlled clinical study is to compare the clinical, radiographic, and patient-centered efficacy of adjunctive application of either enamel matrix derivative (EMD) or hyaluronic acid (HA) gel in conjunction with non-surgical therapy compared to non-surgical therapy alone following a 12-month healing period. Therefore, the following question related to the study is raised: • Does the adjunctive local application of EMD or HA to non-surgical submucosal mechanical treatment of peri-implantitis result in better clinical, radiographic, and patient-centered outcomes compared to non-surgical therapy alone? A total of 60 patients referred to the Gazi University Department of Periodontology, will be randomly assigned to receive the local application of EMD or HA in combination with non-surgical submucosal mechanical treatment of peri-implantitis or non-surgical therapy alone. Clinical measurements will be recorded at baseline, 3, 6, and 12 months after surgeries. Patient oral health related to the treatment procedures using a written questionnaire \[Oral Health Impact Profile (OHIP-14)\] and post-treatment pain and overall patient satisfaction about treatment modalities responses will be evaluated prior to treatment and 3, 6, and 12 months following therapy.

Expression of Epithelial-Mesenchymal Transition Associated Markers in Peri-implant Tissues

Peri-implantitis is an inflammation of bacterial etiology characterized by inflammation of mucous membranes and bone loss around the dental implant. A specific dental plaque bacteria could stimulate host cells, including the junctional epithelium, to secrete a range of pro-inflammatory cytokines involved in initiating the epithelial-mesenchymal transition (EMT) process. EMT has been described as the transdifferentiation of epithelial cells into motile mesenchymal cells. Moreover, cytokines and bacterial products have been highlighted as EMT-predisposing factors. The EMT process could render epithelial cells to lose their cell-cell adhesion and cell polarity that lend these cells to lose their function as an integrated epithelial barrier. E-cadherin is a calcium-dependent cell adhesion molecule that establishes cell-cell adhesion that plays a critical role in maintaining a barrier function in the human epithelium, including gingiva. The loss of E-cadherin is one of the most common biological indicators for EMT. In contrast, vimentin is an intermediate filament expressed in mesenchymal cells and is a canonical marker for EMT, which also promotes cell motility and an invasive phenotype. It is largely reported that EMT is regulated by various transcriptional factors such as Snail Family Transcriptional Repressor SNAIL1 and SNAIL2, zinc-finger E-box-binding (ZEB)1 and ZEB2 and TWIST transcription factors that suppress epithelial marker genes, and activate genes related with the mesenchymal phenotype. Recently, in vivo study has investigated the level of EMT markers in the gingival tissues of periodontitis patients. It was found that the expression of E-cadherin was downregulated while vimentin expression was upregulated. Despite the similarities and differences between the pathogenesis of periodontal and peri-implant diseases, the role of dental biofilm in the etiopathogenesis of the aforementioned diseases was studied largely. While it is now accepted that EMT may potentially play a role in periodontal disease pathogenicity, the possible role of EMT in the disintegration of the peri-implant epithelial barrier and the pathogenesis of peri-implant disease has not yet been investigated.