Extractions and bone grafts

I have chronic periodontitis and severe bone loss.
Unfortunately, #6 needs to be extracted. My dentist proposes to extract the tooth and when the site heals perform a block bone graft (there isn't enough bone for a socket perservation). Originally ridge augmentation, GTR, and block bone graft were going to be perfomed at time of the extraction. After studyng my X-rays my dentist changed his mind. I'm disappointed and concerned; I believe that the bone in that area will recede even more. His response is that I need to grow enough tissue to support the block bone graft.
Hopefully after the area heals I can have an implant. I don't know how long I have to wait for healing...
Should I be worried that I won't be able to have an implant because the graft is not done at time of extraction? I'm concerned that I won't have enough bone to support an impant.

[scottma]

There is almost always enough bone volume for implant placement in canine area,even without rige augmentation .

[texaswavelady]

Thanks for taking the time to address my concerns. I'm so relieved that my fears are unfounded.