Do I Need a Bone Graft for a Dental Implant?

What is a bone graft actually doing?

A bone graft isn't a repair. It works like a scaffold. We place material where bone used to be, and over the months that follow, your own bone grows into it. Some graft materials break down very slowly, so tiny particles can still be there years later, woven into your new bone. That's also why a graft takes time. You aren't waiting for a material to set. You're waiting for your own bone to grow, and bone grows at the speed it grows.

Why does bone shrink after a tooth comes out?

Because the bone around a tooth root largely exists to hold that tooth. The inner lining of the socket depends on the ligament around the tooth for its blood supply, so when the tooth comes out, that lining breaks down. More bone is lost on the cheek side than on the tongue side, and in the front of the upper jaw, that cheek-side wall is usually very thin to begin with. None of this happens because you did something wrong. It's what bone does after a tooth is lost.

How much bone do people lose after an extraction?

More than most people expect. Across the research, the ridge typically loses a few millimeters of width, and the cheek side loses about 1.7 millimeters of height on average. Where you land depends on the site. Most of that shrinking happens in the first few months after the extraction, and then it keeps going more slowly.

Does everyone need a bone graft?

No, and this is the part that gets lost in the conversation. In a large national study of implants, most were placed without a bone graft. Whether you need one depends on why the tooth came out, where it was, and what your scan shows.

How is it decided?

From the scan, not from looking in your mouth. In the upper back jaw, the measurement that matters is how much bone height sits underneath the sinus. There isn't one agreed cutoff for when you need a full sinus graft, and published guidance differs, so I decide from your own 3D scan. The second measurement is how thick the bone is on the cheek side of where the implant will sit. The International Team for Implantology recommends more than 1.5 millimeters there, and when that wall is thin, it recommends adding bone at the same surgery, or in some cases using a narrower implant.

How much time does a bone graft add?

This is the real cost of a graft, and it's measured in months. For sinus lifts and ridge building, the American Academy of Periodontology says the bone is usually allowed to develop for four to twelve months before implants can be placed, though in some cases the implant can go in at the same time as the graft. That sits on top of the time the implant itself needs to heal. Traditionally, implants were left without any biting load for about three to eight months, and a Cochrane review defines conventional loading as anything after two months. How soon yours can be loaded depends on your case. So a graft doesn't just add a step to your treatment. It adds a season.

Do implants in grafted bone work as well as implants in natural bone?

As far as the research can tell, they do about as well. A national study of nearly 159,000 implants found that the success rate at grafted sites was comparable to implants overall. A much smaller study that followed patients for about six to twenty-two years found that upper molar implants in sinus-grafted bone survived about as well as those in ungrafted bone. Two different studies, measuring in different ways, pointing the same direction.

If you've been told you need a graft and nobody showed you the measurement behind it, that's worth a second look at the scan. Here at our Manalapan office, that's exactly what the consultation is for.