<qa>  How long will the tooth brushing process take?A total of 345 adult subjects who are intubated and require mechanical ventilation will be randomly assigned to one of the three different tooth brushing frequency groups: once a day, twice a day or three times a day, up to a maximum of seven days. Teeth will be brushed with a soft child size toothbrush will take approximately 2 minutes. Following tooth brushing, the mouth will be rinsed with alcohol-free mouthwash and oral fluids will be removed with an oral suction tip. Moisturizing gel will be gently applied. The complete intervention requires approximately 15 minutes. 