Periodontitis is a chronic inflammatory disease characterized by the destruction of supporting periodontal tissues. Open flap debridement (OFD) is a commonly used surgical approach for the treatment of deep periodontal pockets when non-surgical therapy is insufficient. However, complete elimination of pathogenic microorganisms remains challenging.

Ozone therapy has been proposed as an adjunctive treatment due to its antimicrobial, anti-inflammatory, and wound healing properties. This randomized split-mouth clinical trial aims to evaluate the clinical effectiveness of adjunctive ozone therapy in patients with Stage III periodontitis undergoing OFD.

A total of 24 systemically healthy patients diagnosed with Stage III periodontitis were included in the study. In each patient, one side was randomly assigned to receive OFD combined with ozone therapy (test group), while the contralateral side received OFD alone (control group).

Clinical periodontal parameters, including plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL), were recorded at baseline and at 6 and 12 months after treatment.

The study aims to determine whether adjunctive ozone therapy improves clinical outcomes compared to conventional OFD alone.

The primary objective of this study is to evaluate the clinical effects of adjunctive ozone therapy on periodontal parameters following open flap debridement (OFD) in patients with Stage III periodontitis.

Periodontitis is a multifactorial disease associated with microbial biofilms that lead to progressive destruction of the supporting structures of the teeth. Mechanical debridement alone may not completely eliminate subgingival pathogens, particularly in deep periodontal pockets and anatomically complex areas. Therefore, surgical intervention such as OFD is often required to provide better access for debridement and improve clinical outcomes.

Ozone therapy has been increasingly investigated in dentistry due to its antimicrobial, anti-inflammatory, and biostimulatory properties. It has been suggested that ozone may enhance wound healing and reduce microbial load when used as an adjunct to conventional periodontal therapy.

This study was designed as a randomized split-mouth clinical trial. Twenty-four patients diagnosed with Stage III periodontitis were included. Each patient contributed two treatment sites, which were randomly allocated into test and control groups. The test group received OFD combined with ozone application, whereas the control group received OFD alone.

All participants underwent initial periodontal therapy, including oral hygiene instructions and scaling and root planing. Standardized clinical measurements were performed using a periodontal probe with the aid of customized acrylic stents to ensure reproducibility.

The ozone application was performed immediately after surgical debridement in the test group, following the manufacturer's instructions. The control group did not receive ozone therapy.

Clinical parameters including plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL) were recorded at baseline, 6 months, and 12 months postoperatively.

The primary outcome of the study is the change in probing pocket depth (PPD). Secondary outcomes include changes in clinical attachment level (CAL), bleeding on probing (BOP), gingival index (GI), and plaque index (PI).

Statistical analysis was performed using non-parametric tests, including the Wilcoxon signed-rank test and Mann-Whitney U test, with a significance level set at p < 0.05.

The findings of this study are expected to provide evidence on the potential benefits of adjunctive ozone therapy in improving periodontal treatment outcomes following OFD.

Inclusion Criteria:

• Adults aged between 25 and 65 years
• Diagnosed with Stage III periodontitis
• Presence of at least 20 teeth
• Presence of periodontal pockets ≥5 mm in at least two teeth
• Indication for open flap debridement
• Systemically healthy individuals
• No periodontal treatment within the last 6 months

Exclusion Criteria:

• Pregnant or breastfeeding women
• Presence of systemic diseases that may affect periodontal healing
• Use of antibiotics or anti-inflammatory drugs within the last 6 months
• Smoking or tobacco use
• History of periodontal treatment within the last 6 months
• Patients with poor oral hygiene compliance

Individual participant data (IPD) will not be shared due to institutional policies and privacy considerations.