I already use a manual syringe on my gums, so my periodontist said this wouldn't do as much for me as my syringe filled with my mouthwash. The WP-450 said only to fill it with water, NOT my mouthwash. I did what the doctor suggested, and that was to return it to the store.
I bought this 3 weeks ago because I have braces. It was the best thing I ever did. It gets food out that the tooth brush does not get and that the proxy brush does not get it was a great investment. The only thing is I wish that the on-off switch was a button that you hold in and let go when you are done.