Dentistry is no different!
When a tooth root is removed from the mouth, the gum and the jaw bone will naturally shrink (atrophy) at the extraction site. This can happen rapidly and in some cases 50% of the bone can be lost in the first 6 months at the extraction site.
This happens because it is the tooth root itself that is required to maintain a healthy jaw bone. So once the tooth root is removed, the jaw bone at the extraction site will rapidly dissolve.
It is the same reason why patients with dentures often complain their plate gets loose over time. This is because the jaw bone beneath the denture is continuing to dissolve over time. Then happens rapidly at first following the extraction of the teeth, but this bone loss can continue over the patient’s life.
There is a long standing myth that replacement of a tooth with a dental implant will maintain the jaw bone. This is simply not true. The jaw bone will shrink regardless of whether an implant is inserted in the jaw bone or not. This dental implant was placed on the same day as the extraction. The bone and gum quickly dissolved around it because it was the tooth root that maintained the jaw bone – not the implant!
In the next example, the implant replacing the first molar did not stop the inevitable collapse of the surrounding jaw bone. From a side angle from this same case, we can see that the normal pink gum tissue (keratinised) has completely dissolved around the implant. The gum is so thin around the implant, it is translucent and the greyish colour of the titanium implant is shining through. So it’s not just the jaw bone that shrinks around the implant over time but also the thicker keratinised gum tissue. A lot of people don’t understand this but it’s a really important point. An absence of this better quality gum tissue around the implant is associated with more frequent implant infections (peri-implantitis).
These implants under this full arch bridge (“All-on-6”) were level with the gum when they were placed. Over time the bone has dissolved around them, leaving the metal implants high and dry. This irritating space is not only visibly ugly but also collects food and is very difficult to keep clean. It shows us that the more tooth roots that are removed, the more jaw bone can shrink over time.
As mentioned before, you will notice how the gum tissue around the implants is very different to the gum tissue around teeth. The quality gum has completely dissolved and the more fragile gum from the inside of the cheek is now inserting around the outside of the implants. This is far from ideal and this softer gum can be easily irritated and can become red and sore. Additional gum grafting procedures are now required to correct this situation.
So when we lose bone, we always lose quality gum tissue.
So implants do not stop the jaw bone from shrinking after the tooth roots have been removed! No matter how much you chew with them. This jaw bone atrophy can continue throughout the patient’s life.
Traditional implant techniques are aimed at minimising the inevitable shrinkage of the jaw bone around the implant following a complete extraction. This is because the implant itself will NOT preserve the jaw bone. Herein lies the problem – traditional techniques can be unpredictable as we never know how much your jaw bone and gum will shrink over time following an extraction.
The mainstay of traditional implant techniques is using bone substitute materials such as heat-treated cow bone such as “Bio-Oss” from Geistlich. This material is used prolifically in implant dentistry because of one very important characteristic – it doesn’t readily dissolve. This means it takes longer for the body to dissolve the jaw bone with these materials present.
Essentially in implant dentistry, we are trying to cheat nature. The body will want to dissolve the jaw bone following a complete extraction of a tooth root but we need this bone to stick around so it will anchor our dental implant. If the bone completely dissolves away, your implant will simply fall out in time. And yes this does happen! Bio-Oss is very expensive and it does not work 100% at stopping the jaw bone shrinking. This means that the jaw bone will still shrink despite the best efforts of the implant surgeon.
When there is bone loss around an implant, the gum also shrinks which can look unattractive.
In the following example, a traditional technique was used on the front left tooth. An implant was placed on the same day the tooth root was extracted. Bio-Oss was also added around the implant at the time of surgery.
The gumline has obviously receded which has compromised the aesthetics. The bits of gum in between the teeth (papilla) have shrunk creating some unsightly black triangles.
Here is another example of a similar pattern occurring. The gum has shrunk making the teeth appear longer. Look how much longer the teeth are on the right side where the implant is, compared to the left side.
In the following example, you can see clearly that jaw bone is very thin around the implant as indicated by the concavity on the yellow dotted line. If you look closely, you can also see pus around the top of the implant (yellow arrows).
The implant was placed only 5 years earlier. The patient’s main complaint was pain and tenderness around the implant crown. When we removed the crown from the implant, there was pus oozing from the implant surface. This patient required a surgical procedure to treat this bacterial infection along with additional bone grafting.
Implant infections are notoriously difficult to treat and sometimes result in the removal an infected implant. Often when an implant is removed following a bacterial infection, the surrounding jaw bone is left in very poor condition making future implant placement at this particular site very difficult. It is hard to place an implant in an area where there is no bone.
Although the implant was easy to remove, there is no easy solution for this patient long-term. There is no jaw bone left at this site to place a new implant. To reconstruct this site will be a big job requiring bone transplanted from another part of the mouth.
Implants are not always this easy to remove following bacterial infections, and in some cases, removal can result in even more bone loss. This is yet another reason why every effort should be by your implant surgeon to preserve your own jaw bone.
Gum grafting is common in traditional implant dentistry. This can be performed to rebuild an implant site where the quality gum tissue has dissolved over time.
This procedure can also be performed to “mask” future bone loss using a traditional implant technique by making the gum tissue thicker.
A small piece of your gum (usually taken from the roof of mouth) is removed under local anaesthetic and transferred to another area of the mouth.
While they can look good initially, connective tissue grafts themselves can shrink over time which can decrease their effectiveness. Soft tissue grafting can be performed at any stage following a traditional implant technique where soft tissue shrinkage is expected or where the gums have already shrunk around the implant.
The longer the teeth have been removed, the more the bone has had a chance to shrink.
This can make it difficult to place dental implants as there is not enough bone to put them in. In severe cases, the jaw bone will need to be reconstructed before dental implants can be placed.
The gold standard for jaw bone reconstruction after severe shrinkage is the use of bone block grafting. This is where a small piece of jaw bone is taken from the chin or more commonly around the back of the lower jaw and then repositioned into the deficient implant site. This is definitely a more involved procedure and is often performed under general anaesthesia in hospital. Even this new bone is subject to shrinkage over time – so often non-resorbable products such as Bio-Oss are used in combination with block grafting to mitigate future bone shrinkage.
In this example, severe atrophy of the front of the jaw bone had occurred underneath a partial denture over many years. Bone block grafting was required first to rebuild the jaw bone before implants could be placed. This procedure was performed with the help of an anaesthetist so the patient was comfortably asleep for this procedure. A piece of jaw bone was taken from the back of the lower jaw and then transplanted into the new implant site. After 4 months of healing, the implants were placed into the newly constructed jaw bone. Notice how much thicker the jaw bone is in the second picture after a successful bone block grafting procedure.
In the below example, both upper first molars were replaced with implants. On the left side a traditional technique was used and over time the jaw bone has clearly dissolved. The was despite bone grafting with Bio-Oss performed at the time of surgery.
Compare this with the right side whereby the jaw bone was maintained naturally using the CastleWall® Surgical Technique.
More available jaw bone means a stronger implant and a more lifelike crown. Notice the difference in the size of the crowns in this case.
Traditional
CastleWall
FIND US IN TOOWOOMBA
Heasley Dental
98 Margaret Street
Toowoomba QLD 4350
QUICK LINKS