The before period (control phase, 6 months): standard oral care 3 times a day in every consecutive intubated patients in the participating ICUs The interphase period (1 month): formal training of all the nurses, physicians and residents on the use of toothbrushing during oral care The after period: (study phase, 6 months): standard oral care with tooth brushing 3 times a day in every consecutive intubated patients in the participating ICUs