I wonder if that extra depth, length of time and frequency of HBOT makes the difference between whether it is effective or not for some people – and may be that is why funding isn't available for the HBOT at MS therapy centres any more. Problem seems to be, for me anyway, the length of time it takes to get the treatment. The other week my tooth started to play up again and the gum felt a bit raggedy. Now it feels that a little bit of bone is poking through. I'm going on holiday next week, so I'm hoping that things will not deteriorate while I'm on holiday. I am so cross that I've had to wait until July for the HBOT - if I'd had it sooner..... They know that ORN is a degenerative condition yet they leave you hanging and waiting without treatment for so long.