Please choose the correct ending to complete the given sentence: Health: [header] How to choose an electric toothbrush [title] Purchase a sonic toothbrush for an inexpensive, dentist-approved option. [step] 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.

Ending1: Popular sonic toothbrush brands include sonicare, issa, and oral-b pro. [title] Get an ultrasonic toothbrush for the best results possible. Ending2: " sonic brushing " is a word that describes the outneeded frequency, duration, and sheen components that are needed to keep the bristles healthy. There are two kinds of sonic brushing: the regular type and the computer standard. Ending3: [substeps] Sonic brushes are made from natural household materials and much more expensive than their synthetic counterparts. Sonic brushes should be dried off after use. Ending4: Do not assume that by buying a sonic toothbrush you can automatically remove unwanted dead hair from the brush. [title] Find a regular toothbrush for frequent use.

Answer format: ending1/ending2/ending3/ending4