Henry Royle Evatt took on his father's dentistry business on his death in 1836. Henry advertised as both a surgeon dentist and an insurance agent. He spent some time in the 1840s splitting his time between Sheffield and Leeds, then the family moved to Trafalgar Street in Leeds.
Lack of early records
I was not able to find any records of Henry's birth in the Quaker records, nor of the marriage of his father William
Henry Royle Evatt was also a licensed medicines dealer who dispensed cures for secret diseases under the name of Henry Royle. He advertised regularly throughout the 1850s and was associated with a Dr Wilkinson with whom he seems to have fallen out - if I have interpreted the adverts correctly.
Connection to William Evatt
The link between Henry Royle Evatt and William was made due to an advert Henry took out in the Sheffield papers announcing that he has taken over the dentistry practice from his now deceased father. This was in 1836. There is also a paper describing his succedaneum where he talks about his father having been a dentist for 50 years.
Occupation on Marriage
Henry married Matilda in 1834 so I have not obtained a certificate. However there is a notice in the Sheffield papers and it says that Henry is a joiner
Quakers were not allowed to 'marry out' until the 1850s so the fact that many children of Quakers did indeed marry people of other religions caused a significant decline in Quaker numbers.