The trumpet and the toothbrush - can you help?

This was originally sent as a real email by my friend and colleague Dagmar. This is a true story. The names have not been changed to protect the innocent.

Dear Dr. Fry,

I am writing from Toronto, Canada, to solve a mystery that has recently come to light. My brother, Tom, who is now 48 years old, recently decided to take up his trumpet again, which he started playing at around age 12. In doing so, he found the trumpet sounding rather muted, so called up my brother-in-law, David, a musician, to query why the trumpet might be sounding dull. David asked Tom if he had ever cleaned the trumpet to which my brother answered no, and so naturally this was David's advice. Tom cleaned the trumpet and what he found deep inside the bell was an unbelievable surprise - a toothbrush! - translucent green, 6-sided and beveled - with the printing: "Prevent 35" on one side, and "Dr. Robert W. Fry" imprinted in white on the other.

There are no Dr. Robert W. Fry's in our area, nor in Canada for that matter, so hence a Google search and finding you!

The trumpet was purchased from the somewhere in the U.S. around 1972. My thoughts...Either the trumpet came with the toothbrush, or someone put it in there during Tom's high school band trip to Michigan in 1974, or...the young man (a fellow high school band mate in Hamilton, Ontario) whom my brother lent his trumpet to, lost the toothbrush in there (the trumpet was returned to my brother with a dent!).

Any clues to solving this mystery if in fact you are the Robert W. Fry..?

Thanks for your help and any insights you might have!

Best regards,
Dagmar