In intensive care, Ventilator-Assisted Pneumonia (VAP) is common, with an estimated incidence of 12.6% in 2002. This infection is related to micro-inhalation in the trachea of bacterial colonies present in the mouth. However, no scholarly recommendation has been made concerning how mouth care should be carried out in order to prevent VAP. We hypothesize that intensified mouth care using a standard protocol that includes teeth brushing would be more effective than procedures currently being used to limit tracheal colonization. The objective of this research project is to compare two mouth care protocols and to evaluate endotracheal colonization after 14 days for patients who have been on mechanical ventilation for at least 24 hours. Materials and Methods: This is a randomized trial neutral for treatment. 91 patients will be assigned to each group (a total of 182 patients) in order to demonstrate an increased average delay of tracheal colonization of two days with a power of 80%. The first group will receive a protocol consisting of three sessions per day of mouth care according to a (standard) protocol (including use of chlorhexidine 0.12%). The second group will benefit from an intensified program consisting of six sessions per day of mouth care (two teeth brushings with a suction tooth brush, and four sessions per day of mouth care with chlorhexidine 0.12%). Patients who are eligible are adults who will be on ventilation for at least 24 hours. Patients who will be excluded are those who have pneumonia or colonization on admission (spectrum cytology examination Day 0 positive, or admission is documented as for pneumonia), and those who have been on ventilation more than 72 hours. The criteria for the principal results will be survival without colonization of tracheal (aspirations) (greater than 105 CFU/ml). Other criteria for secondary results will allow us to test to the hypothesis, such as rate of tracheal colonization and VAP, length of time of ventilation and hospitalization, improvement of the state of the patient’s mouth, and so on. The benefits expected from this study concern the prevention of nosocomial infections by reduction of tracheal colonization with a reduction of morbidity and mortality. It will also allow a standardization of nursing care practices, and formalization of evidence-based practices. Finally, we hope to see a reduction in costs associated with VAP. A pilot study is currently ongoing and a project proposed for the 2011 PHRIP.