👉 Aspera, also known as Aspiration, is a type of disease characterized by the inability to produce saliva. This condition can be caused by various factors such as genetic mutations or immune system issues, and it can lead to difficulties in swallowing food and speaking. The exact cause of Aspera remains unclear due to its complex etiology, but some theories suggest that it may be related to a deficiency in certain enzymes or hormones that are involved in the production and breakdown of saliva. Additionally, some