Western medicine concurs that at the very least tongue scraping is beneficial for dental health, with several studies showing that scraping can help remove the build up of volatile sulfur compounds on the tongue. Tongue scraping improves good breath and overall dental health. (http://health.howstuffworks.com/wellness/oral-care/products/tongue-scrapers-really-help.htm).
One doesn't have to purchase an official tongue scraper (pictured above), a simple spoon (also pictured above) will also work.
Beyond the health benefits tongue scraping offers, if one meditates on the tongue first thing in the morning, this cleansing ritual can become an opportunity to reflect on the first two Yamas Ahimsa (nonharming) and Asteya (truthfulness). The tongue scraping ritual can be a way of resetting whatever speech we might have made that wasn't in keeping with our best nature. As we clean the tongue at the beginning of each day, we might reflect on how we want to use our words to communicate, with our students, our colleagues, our friends and family--a little bodily ritual with ethical significance.
How might we metaphorically keep the tongue clean as we go about our days?