Having given birth to a child who has since developed an unnatural passion for dental hygiene, we've never had trouble getting him to brush his teeth before bed every night, and yet here I go anyway, giving you advice about how to get your kid to brush his teeth.
(I'm not a big believer in tricking kids into doing what they're supposed to do by going out of my way to make those things seem fun! and exciting!, but a few bells and whistles never turned anyone into a sociopath, so I figure what's the harm, especially if the alternative is extensive orthodontia.)
My son got his during a daycare sleepover (we forgot to pack his toothbrush from home and he was apparently so distraught Daycare Lady had no choice but to give him a light-up one she had in storage for her daughter), and I can't find that exact brand available anywhere in the U.S., but here's a two-pack from Dr. Fresh on Amazon. They're like WHOA expensive for a toothbrush, but certainly less expensive than a root canal, so do what you gotta do, I guess.
Happy brushing, kids.