The top recommended feeders are those made of stainless steel and silicone.
STAINLESS STEEL - Stainless steel is one of the safest food containers. It will not trap dangerous bacteria or leach harmful chemicals. Clean it out after every use with soap and hot water. It can also be cleaned in the dishwasher. For an eco-friendly alternative use a simple mixture of vinegar and water.
SILICONE - Silicone is one of the newest alternatives on the market today. Nontoxic, nonstick and rubber-like. High quality silicone products are highly heat-resistant (can be used with boiling water or in the oven if needed), does not retain stains or odors, and has collapsible features.
ELEVATED FEEDER - Consider choosing an elevated feeder. It is simply an elevated stand used to raise the bowls above floor level. It has a number of benefits. The most important is the improved comfort for your dog. An elevated feeder keeps the feeding area cleaner - less food and water on the floor.
CERAMIC OR STONEWARE - Other choices include ceramic or stoneware dog food bowls. Upon choosing stoneware make sure the bowls are dishwasher safe, lead-free, and food-grade glaze. Discard dog bowl if they become chipped or cracked.
Many people choose a plastic dog bowl because the are ready available and inexpensive. However, it may not be the best choice for your dog's food bowl. Plastic can get small scratches over time which trap and hold bacteria that can not be removed with cleaning. A determined chewer may end up chewing the plastic bowl, possible ingesting pieces of plastic.