Many people fear "the dentist" and some just hate them. I don't, but I understand. Though they are healers, they are also pain-dealers; if it doesn't hurt now, thanks to novacain et. al., many times it'll hurt later. (Surgeons don't get the same bum rap, even though the job description is the same.) I was kidding my periodontist one time about "the damage" intrinsic to any procedure; primary "damage" to the problem area, secondary damage to the palate/gums from the pain-blocking needle, tertiary damage to the corners of the mouth from the instruments themselves. Come the evening or next day, everything is sore and tender; however, when that fades, voila! no more toothache.
My grandmother had a very low pain tolerance and hated the idea of "dentist". At her passing, she had very few teeth left and those that she had were the rottenest I've ever seen in a human mouth.
Dentists know all this. It must be wearing for those upon whom it weighs.
I suspect these "suicided" banker types either had a very clear view of how deep in the sht we are, or they knew something not many do.