jenny,

In the lower front area of the mouth the jaw bone is by nature very thin and narrow. A long standing infection, which is what you had with your 20 year old root canaled tooth, eroded the jaw bone thus compromising the integrity of the bone. Bone grafting in this area is tricky even if the bone had been healthy. The greater the loss of bone, the higher the risk of failure with the graft and the dental implant.

Bone graft material does not provide new jaw bone. It is surgically placed to encourage the body to grow new bone cells which integrate with the graft material until the new bone becomes solid. However, bone grafts need to be placed "inside" of healthy bone in order for the cells to grow. If there is inadequate healthy bone and the graft is placed next to or on top of existing bone, little to no integration will occur. The graft would then be similar to a pebble sitting in the tissue that it was placed in. In those cases, the graft can be palpated or felt on the outside of the gum in the area where the roots of the extracted tooth use to be. The long term success rate of this type of graft and even the dental implant would be very low.

When there is less than adequate bone or very thin bone, the implant may not be surrounded by bone. In that case, the bump that is felt in that gum area can be the actual dental implant.

If the lump were your chin bone.... it would not feel like something new to you as nothing was altered regarding your chin. Right?

The lump could also be a cyst that is not being diagnosed.

Routine dental xrays and panoramic xrays are 2 dimensional and are limiting for a proper diagnosis in cases like yours. You would need to see an oral surgeon who has a 3D dental scan machine which would give a broader view of that area.

I hope this information is helpful. Let us know how you're doing.
Bryanna