The anteverted pelvis and back posture relate to head, neck and oral posture, which is essential to straight teeth and orthodontics.
Myofunctional therapy and an oral work out. Build up both the tongue tone and muscle tone, while forcing a good level of coordination and learning. Slow your breathing and increase the rate of chewing.
Stick joga by Arthur Faygenholtz is a good and simple way to improve body posture
Bearfoot shoes can help body posture thus head and neck posture which leads on to straight teeth.