Summarize this article:

When visiting a dentist, most will recommend you purchase a sonic electric toothbrush, or a brush that can create thousands of oscillations per minute. These provide a deep, thorough cleaning at a reasonable price, with many models costing under $100. Popular sonic toothbrush brands include Sonicare, ISSA, and Oral-B Pro. While similar in design to sonic brushes, ultrasonic brushes create millions of oscillations per minute instead of thousands. Though typically more expensive than their sonic siblings, coming in at well over $100, they provide the best cleaning possible short of visiting an actual dentist. Popular ultrasonic brands include Smilex, Emmi-dent, and Ultreo. Companies often use the terms sonic and ultrasonic interchangeably, so check the brush's oscillations per minute to make sure it is actually ultrasonic. If you're sick, traveling, or otherwise in need of a cheap, disposable electric toothbrush, try purchasing a basic battery-operated one. Though low-powered, they typically cost only a few dollars, making them a great option for flights, sleepovers, and other times when your normal toothbrush won't be available. If you're getting an electric toothbrush for a child, try buying one themed around their favorite TV show, video game, singer, or cartoon character. These brushes typically cost only a few dollars, meaning you can replace them easily when damaged, and often include timers to make sure the child brushes long enough. These brushes are typically low-intensity, so kids with severe teeth issues may need something more powerful.

Summary:
Purchase a sonic toothbrush for an inexpensive, dentist-approved option. Get an ultrasonic toothbrush for the best results possible. Buy a cheap electric toothbrush to have something disposable. Grab a themed toothbrush for kids.