This randomized controlled trial aims to evaluate the effect of two oral care methods on oral bacterial colonization and ventilator-associated pneumonia (VAP) in mechanically ventilated intensive care unit (ICU) patients. The study will be conducted in the Anesthesia and General Intensive Care Unit of a hospital in Turkey between October 2025 and June 2026.

A total of 72 patients who meet the inclusion criteria and provide informed consent will be randomly assigned to two groups. Thirty-six patients will receive oral care with a pediatric toothbrush, and 36 patients will receive oral care with a sponge stick, for five consecutive days. Standardized oral care sets containing 0.12% chlorhexidine, recommended for VAP prevention, will be used in both groups.

Oral health and oral care frequency will be assessed daily using the "Oral Care Assessment Scale in Intensive Care Patients (OCAS-ICP)" developed by the researchers. Oral swabs will be collected on Day 1 and Day 6 and analyzed in the microbiology laboratory for colonization with Staphylococcus spp., Pseudomonas spp., and Acinetobacter spp.

The Clinical Pulmonary Infection Score (CPIS) will be used to monitor the development of VAP, including six parameters: fever, leukocytes, tracheal secretions, oxygenation, chest radiography, and culture results. Patients will be evaluated on Days 1 and 6 for changes in oral flora and VAP occurrence.

This study will provide evidence on the effectiveness of different oral care devices in preventing VAP and improving oral health in mechanically ventilated ICU patients.

This study is designed as a randomized controlled trial to evaluate the effect of two different oral care methods on oral bacterial colonization and the incidence of ventilator-associated pneumonia (VAP) in mechanically ventilated patients in the intensive care unit (ICU). The two methods to be compared are oral care performed with a pediatric toothbrush and oral care performed with a sponge stick.

The study population will consist of patients receiving respiratory support with mechanical ventilation in the Anesthesia and General Intensive Care Unit of a hospital in Turkey, between October 2025 and June 2026. A total of 72 patients who meet the inclusion criteria and provide informed consent will be included. Patients will be randomly assigned to one of two groups: 36 patients will receive oral care using a pediatric toothbrush, and 36 patients will receive oral care using a sponge stick, for a period of 5 consecutive days. In both groups, standardized oral care sets containing 0.12% chlorhexidine, a solution recommended for the prevention of VAP, will be used.

Oral assessments and the frequency of oral care are important for effective nursing practices in the ICU. However, there is currently no validated measurement tool in the national or international literature that evaluates both oral and clinical conditions in this patient population. For this reason, the "Oral Care Assessment Scale in Intensive Care Patients (OCAS-ICP)" developed by the researchers, will be applied daily for 5 days to assess the oral health status and oral care needs of patients.

Oral swab samples will be collected from patients on Day 1 (baseline) and Day 6 of the study and evaluated in the microbiology laboratory. The analysis will focus on colonization with bacterial species associated with VAP, specifically Staphylococcus spp., Pseudomonas spp., and Acinetobacter spp. Results will be recorded on the "Microbiology Patient Follow-up Form."

To monitor the development of VAP, the Clinical Pulmonary Infection Score (CPIS) will be used. This scoring system includes six parameters: fever, leukocyte count, tracheal secretions, oxygenation, chest radiograph findings, and culture results. It has been reported that a CPIS score above 6 is highly reliable for diagnosing pneumonia, with 93% sensitivity and 100% specificity. CPIS data will be collected using the "Clinical Pulmonary Infection Score Patient Follow-up Form" within the first 24 hours of ICU admission and during follow-up.

The primary outcomes will be the change in oral bacterial flora and the incidence of VAP between the two study groups. The findings are expected to provide evidence on the effectiveness of different oral care devices in preventing VAP and improving oral health in mechanically ventilated patients in the ICU.

Inclusion Criteria:

• Patients who have been on invasive mechanical ventilation for less than 24 hours.
• Patients who provide informed consent through their legal representative or themselves if capable.
• Patients with no prior oral surgery, no head or neck trauma, and no contraindications to oral care.
• Patients aged 18 years or older.

Exclusion Criteria:

• Patients under 18 years of age.
• Patients who have been on mechanical ventilation for more than 24 hours before enrollment.
• Patients with oral surgical procedures or trauma to the head or neck.
• Patients with contraindications to oral care, such as severe oral bleeding, mucositis, or active oral infections.
• Patients or legal representatives who do not provide informed consent.

The decision regarding individual participant data (IPD) sharing has not yet been made. Due to ethical considerations and patient confidentiality concerns in critically ill populations, the research team remains undecided about whether de-identified data can be made available in the future.

Masking: Single-blind (independent outcome assessor)