The main reasons for choosing water-injected teether are as follows:

1. **Safety**: Water-injected teethers are made of high-quality polymer materials. These materials have undergone strict safety testing and are non-toxic and harmless, and do not pose a threat to the baby's oral health. Safety is the primary consideration for parents when choosing teething products for their babies, and water-filled teethers undoubtedly have significant advantages in this regard.

2. **High comfort**: The texture of water-injected teether is soft and can adapt well to the baby's oral environment, providing the baby with a comfortable chewing experience. During the baby's teething period, the gums will feel itchy and uncomfortable. The soft texture of the water-injected teether can effectively relieve this discomfort and help the baby get through this special stage.

3. **Multi-functionality**: The water-injected teether can not only be used as a teeth grinding tool to relieve the discomfort of the baby's teething period, but can also massage the baby's gums to promote healthy tooth growth. In addition, by chewing water-filled teethers, your baby's chewing ability and hand-eye coordination can also be exercised and improved.

4. **Easy to clean and maintain**: Water-injected teethers are usually designed with ease of cleaning and maintenance in mind. They can be easily removed and cleaned, are less likely to breed bacteria, and help maintain your baby's oral health.

5. **High cost-effectiveness**: Compared with other teeth grinding products, the price of water-injected teether is usually more affordable and more cost-effective. Parents can provide their babies with a safe, comfortable, and multifunctional teething tool without spending too much money.

In summary, water-injected teethers have become an ideal choice for babies during the teething period due to their safety, comfort, versatility, ease of cleaning and maintenance, and high cost performance.