A dentist has been discovered dead in his mansion along with his wife and daughter in a suspected murder-suicide.

The bodies of Dr James Choi, his wife Myoung, both 52, and their 15-year-old daughter Grace were found in their $1.7 million home in Johns Creek, Georgia on Sunday.

Investigators made the grim discovery during a routine welfare check at the sprawling six-bedroom property, situated within the gated community of St Ives Country Club.

Police have not disclosed the cause of death out of respect for the family but believe Dr Choi killed his family and then himself.

According to his practice website, Dr Choi, who was originally from South Korea, said his prime goal was to “make patients smile”.

Grace, an accomplished violinist, had performed at Carnegie Hall in New York as recently as January.