I very much liked this story. It was short, funny, and well-acted. The SF element kind of took a backseat to the character interaction, but I didn't mind that because, despite the fact that the author doesn't really tell you a lot about them, you still know everything you need to know about both the dude and his toothbrush.
I was very pleased with the acting -- I think the reader got the saccharine-happiness of the toothbrush down pat, and did a good job with the owner, too.
The last line was nice, but not 100% unexpected.
I think, after a few weeks of heavy SF, we need stories like this, or even like Squonk (which I've said is not my cup of tea, though I can appreciate how good the story is).