To put it simply, mouthpieces generally help with sleep apnea. However, they may not work for everyone. They are usually the best option for people with mild to moderate cases of sleep apnea or those who find CPAP machines very uncomfortable. Additionally, as there are many variations of mouth guards on the market, you might have to try different products before you find one that works best for you. Luckily, you have this guide to make this a whole lot easier.