Yes, I know Gum is an imported brand, but it's the only picture of toothpaste for the Japanese market that I have.
During my earliest days in Japan, someone I worked with "warned" me not to use Japanese toothpaste because it supposedly had sugar in it or was an ineffective dentrifice. I'm not sure if that is or was true, but I do know that Japanese toothpaste leaves something to be desired. For one thing, the taste is strange in some brands. It has a strange almost bubblegum-like flavor. Also, I've read that the percentage of fluoride is lower compared to Western brands (and that this may account in part for the sad state of Japanese teeth despite readily available dental care and relatively good oral hygiene practices). This requires more frequent brushing, which is great for toothpaste sales but not so great if you're too busy or not in a position to carry a brush at all times.
I've had to buy imported toothpaste by the case at an inflated price to avoid Japanese toothpaste and I won't miss that.