Could a nasal spray from teeth stem cells ease severe schizophrenia?

This is a very early, small study to see if a nasal spray containing tiny particles from dental stem cells is safe and might help with the hard-to-treat 'negative' symptoms of schizophrenia, like social withdrawal and lack of motivation. Fifteen adults with long-term, treatment-resistant schizophrenia will use the spray twice a week for two months while doctors closely monitor their health and symptoms. The main goal is to check for safety and side effects, while also looking for any early signs that the treatment might be helpful.