Not to put words in his mouth, but I think the above poster was referring to having medical insurance cover said dental costs because the loss of bone in the jaw would cause other medical complications down the line in young people.
That's how I took it, but don't dentists normally put the implants in? If dental insurance is paying for the implants and medical insurance is paying for the bone damage, there isn't a lot of incentive for the dental insurance to pay for expensive implants.