This randomized clinical trial aims to compare the clinical and radiographic outcomes of the Vector®️ ultrasonic system and mini-five curettes in non-surgical periodontal therapy. Patients diagnosed with periodontitis will be randomly assigned to either ultrasonic instrumentation or manual instrumentation. Clinical periodontal parameters and radiographic bone level changes will be evaluated at baseline, 1, 3, 6, and 12 months. The primary objective is to assess differences in clinical attachment level and probing depth reduction between the two treatment modalities.

Periodontitis is a chronic inflammatory disease leading to the destruction of supporting periodontal tissues. Non-surgical periodontal therapy is the first-line treatment and includes mechanical debridement using manual or ultrasonic instruments. The Vector®️ ultrasonic system is designed to provide minimally invasive debridement with reduced trauma to root surfaces and surrounding tissues.

This randomized, controlled, single-blind clinical trial will compare the effectiveness of the Vector®️ system and mini-five curettes in patients diagnosed with periodontitis. Participants will be randomly allocated into two groups: the ultrasonic instrumentation group (Vector®️ system) and the manual instrumentation group (mini-five curettes).

Clinical parameters including probing depth (PD), clinical attachment level (CAL), bleeding on probing (BOP), and plaque index (PI) will be recorded at baseline and at 1, 3, 6, and 12 months. Standardized radiographic examinations will be performed at baseline, 6 months, and 12 months to evaluate radiographic bone level changes.

The primary outcome measure is the change in clinical attachment level at 12 months. Secondary outcomes include probing depth reduction, bleeding on probing, and radiographic bone level changes.

The study is conducted at Hacettepe University Faculty of Dentistry, Department of Periodontology. Ethical approval has been obtained from the Hacettepe University Clinical Research Ethics Committee.

Inclusion Criteria:

Adults aged 18-65 years Willing to participate and provided written informed consent Presence of single-rooted teeth in both maxilla and mandible with vertical bone defects (radiographic intrabony defect ≥2 mm and probing depth ≥5 mm) Diagnosis of Stage III or Stage IV periodontitis Systemically healthy or Systemically healthy patients or American Society of Anesthesiologists (ASA) physical status I-II.

Exclusion Criteria:

Periodontal treatment within the last 6 months Teeth with furcation involvement Smoking more than 10 cigarettes per day Pregnancy Age under 18 years Patients unwilling to attend regular follow-up visits Previously endodontically treated tooth at the treatment site Poor compliance with oral hygiene instructions Single-rooted teeth with horizontal bone loss extending close to the apical third Teeth with mobility grade II or III Previous flap surgery or regenerative periodontal treatment at the study site

The examiner responsible for clinical measurements is blinded to the treatment allocation.