Are acrylic orthodontic retainers safe to use?

Yes: Acrylic retainers are very safe to wear/use. The issues with "commercial" acrylic and pba's are not to be confused with orthodontic acryilc based retainers.

Yes: Orthodontic retainers made with acrylic have been used safely for decades. Unless you have an unusual allergy to acrylic you should be fine.

Yes they are: Acrylic orthodontic retainers have been used safely for more than 100 years. The only risk is patient allergy to acrylic, and this is seldomly reported.

Retainer: Yes, assuming no strange allergies exist.

Yes: The acrylic used in orthodontic retainers is medical grade, and poses no health threat.

Absolutely: Studies of tooth movement are very consistent. If you retain teeth 6-8 hours a day, your teeth will not move! so basically, wearing your retainer during sleeping hours will guarantee your teeth will not move. Consistency is the key. And acrylic is absolutely the material of choice.

Of course: If unsafe they would have been banned by the fda. Acrylic has been used in dentistry for over a century. There are an infinitesimally small group of people allergic to acrylic, but less than are allergic to strawberries or chocolate. Don't worry. Chance of allergy less than chance of being struck by lightning.

Yes: There is not reaction nor is there any evidence they cause any systemic problems.