This is the second installment in my blog series about dental implant surgery. Last week we talked about what to expect when a tooth must be removed and the conditions necessary for replacement with an implant. Today, we will discuss what happens when the tooth has been missing for a prolonged period of time, such as a year or more.

Installing a New Implant to Replace a Long-Term Missing Tooth

When a tooth is removed, the bone holding the root into the jawbone, called an alveolar bone, slowly “melts away.” Well actually, it’s not that slowly. The truth is that up to 50% of the bone that will be lost occurs within the first 3 months after the tooth is removed. There is generally a total loss of up to 60% of the supporting bone in the first year.

So, now the question is: what can be done when the patient wants an implant and there simply isn’t enough bone to support the implant? Let’s go back to the telephone pole scenario we discussed last week. This time, instead of placing a telephone pole into a swimming pool, we are trying to place the telephone pole into a baby’s tiny bathtub. There simply isn’t enough space for the pole to be adequately supported.

When this occurs, the surgeon is able to use bone grafts to help the patient regrow the bone through a process called “bone augmentation.” This is a minor surgical procedure that involves the surgeon inserting bone to increase the height and/or width of the existing bone. The surgeon will use bone from one of three sources:

1. Donated human bone from a “tissue bank,” called allograft bone, which is fully sterilized and purified to eliminate all risk of infection,
2. Bovine (cow) bone, called xenograft bone, similarly treated to eliminate risk of infection, or
3. Bone taken a nearby location in the patient’s mouth, this is called an autograft.

The surgeon may use any combination of these bone sources, but in order to keep patients comfortable, surgeons will generally try to avoid the third bone source.

This procedure consists of carefully “raising the gums,” which is much like peeling a banana. The surgeon then places the new bone against the existing bone where an increase in dimension is needed. Bone used for this purpose is loose and particulate, much like fine gravel, and is held in place with a blanket-like material, referred to as a “membrane.” The gums are then repositioned over the bone and secured with stitches, sometimes called sutures.

After the bone augmentation procedure, the patient can usually resume normal activities the next day. However, the patient will require about 6 months for the bone graft to fully mature into bone strong enough to support an implant. After the bone graft has matured, the dental implant can be safely placed into a site that is now strong, offering the patient significantly improved results and implants that function and look great. In most cases, this procedure helps the implant last for many years into the future.