Have you been told you don’t have enough bone to have a dental implant? Or maybe you have a front bridge replacing a missing front tooth which has teeth that look way too long in some spots? Or maybe you have no bone left to hold your dentures in place and you want to secure them in place somehow? If you experienced any of these problems, you may be a candidate for bone grafting. When you don’t have enough of your own natural bone for support then you can almost always add some through several techniques. Dr. Tony Kim at his Honolulu cosmetic and implant dental office, you can see if you’re a candidate for bone grafting and have a chance to ask questions in a consultation appointment.
What is a dental bone graft?
A bone graft is material added to your jaw to either grow bone or to maintain the bone you already have. There are many materials that bone grafts are made from, the major types are discussed below. The graft material that is added to the area holds the space and resorbs away slowly while your own natural bone grows in it’s place. After several months of healing time the new bone should be ready and fairly stable. Because it’s very important to avoid the graft site to get infected, antibiotics will be prescribed to minimize the chance. Our office is very aware of the over prescription of antibiotics prevalent in medicine but this is one of the situations where prophylactic use of antibiotics often makes a case succeed or fail early in treatment. If a graft becomes infected then it may have to be removed and then a new one placed at a later date, further delaying treatment and resulting in extra surgeries.
Bone Grafting Materials
- Autograft – This is bone taken from your own body and placed into another area. The bone can be taken from the pelvis, jaw, chin, skull, and other areas. This bone is considered to be the best for grafting because there is the smallest chance of rejection. The main disadvantage is that you require a second surgical site for removal of the donor bone. The donor sites that are in the mouth usually will not require hospitalization but removal of the bone from the other parts of the body will require a hospital stay.
- Allograft – This type comes from other human cadavers. There are bone banks that process and purify the bone so that it can be placed in other people. This bone is tested to make sure there are no bacteria, viruses, and other potentially harmful microbes. This is one of the most common types of grafts available and is nice because there is a low rejection rate and does not require a second surgical site.
- Xenograft – These grafts come from non-human but non-synthetic sources. Cow bone is the most common and it’s useful where the particles need to stay in place longer. Cow bone resorbs slower than human bone so it helps maintain shape in the initial stages.
- Alloplastic graft – There are synthetic graft materials with varying properties. Some resorb and help form bone and others are there permanently and don’t resorb away but rather help maintain the shape.
Types of Bone Grafting
- Socket grafting is the most common type of grafting. It involves filling the empty tooth socket after a tooth is extracted. Once a tooth is pulled out, the surrounding bone resorbs away quickly in the initial year after extraction and then slowly loses bone over the following years. The bone loss can be slowed down tremendously by adding a bone graft immediately after tooth extraction. By maintaining the bone levels, the appearance of the gums stays level which in turn helps the cosmetic appearance of the bridge or dental implant used to replace the missing tooth. When too much bone is lost, the gum tissue shrinks away too leaving a replacement tooth looking longer than it was originally.
- Ridge grafting is another common type of bone grafting. When the width or height of bone is too narrow or short then bone can be added. Usually this type of grafting will require the use of membranes. This type of grafting is also called guided bone regeneration. The membranes hold the bone particles or pieces into place and prevent the gum tissue from penetrating the graft area which would reduce the quality of bone created in the site. Sometimes the ridges are also reinforced with stiffer titanium frameworks to really protect the shape of the surgical site. Your oral surgeon or dentist performing the grafting will know what type of materials that will be necessary.
- Sinus lifts or sinus grafting is used when there is not enough bone in back of the upper jaw. Our sinus cavities rest against the bone that surrounds the back upper teeth. When teeth are lost in this area the bone shrinks away very quickly and the sinus hangs down lower as the bone disappears. A sinus lift can be performed to literally push the floor of the sinus upwards so that bone can be placed in the upper jaw again. This type of grafting can be very successful and allows placement of implants in the very important molar areas. Sometimes sinus lifts can be done with instruments called osteotomes which are literally tapped upwards. This technique is the most minimally invasive technique with a minimal amount of discomfort. A window sinus lift requires a surgery and is used when there is not enough bone to do a osteotome lift. The lateral window approach is a more invasive type approach but the office has equipment to keep the surgery as conservative as possible. Once the sinus is exposed, it is gently pushed up creatig space where the graft materials are placed. Both types of sinus graft surgeries have a high chance of success but just like any surgery, they require strict post operative instructions to increase chance of success. You should not blow your nose or forcefully inhale mucous in the nasal passages while the sinus graft is healing in it’s initial week. Antibiotics and antihistamines are necessary to keep the sinus areas clear and the avoid infections.
Once a bone graft is placed, the typical healing time will be anywhere from 4-6 months on average but may be up to 6-8 months for more complicated grafts. Some membranes and meshes have to be removed after the bone heals which would require a 2nd surgery. But other membranes resorb slowly over time and disappear on their own without requiring a separate removal appointment. Your surgeon will know what type of membrane will be the best for your grafting situation.
Additional Modifiers and Materials in Grafting
There are several different types of materials that can be added to enhance bone formation and tissue healing. These are added to the bone graft material and placed into the socket or ridge. There are several materials that are taken from your own blood like platelet rich plamsa (PRP), platelet rich growth factor (PRGF) and platelet rich fibrin (PRF). These healing factors can greatly aid in healing times, post op discomfort and better results. There is also something called bone morphogenic protein (BMP) which are growth factors which can help add bone. And don’t forget, membranes, meshes and other materials may be used for better results. Sometimes the additional cost of bone grafting may seem high but building a strong foundation is critical for long term success.