It is not every day I see a case like this. This patient is going to lose her lower first molar which is the one that is second from the back typically if you are missing your wisdom teeth. It is the most common tooth to be pulled mostly because it has been in your mouth since you were 6 years old. In her case, the tooth is not savable because of severe root decay on an existing crown with a root canal. (Remember that you can get a cavity on a crown which typically happens at the edge or “margin” which is where the tooth meets the crown near the gum line.)
Because the procedure is done in stages, it typically takes 6-12 months to complete often based on how hard or soft your bone is or how fast or slow your bone heals.
What is so unique about her case is the depth of her nerve!! It is DEEP in the jaw! Most of the time, an immediate lower dental implant is not able to be done because this nerve is too close to the surface. Typically I like to place the implant a minimum of 1-2 mm away from the nerve. So if the nerve is high, your oftentimes limited to a short implant or an implant that cannot get enough stability when it is placed into a socket. This nerve gives sensation typically to the lip and chin. There are other branches of the third division of the trigeminal nerve that give sensation to the cheek and tongue.
The nerve is like an electrical cable which carries sensation back to your brain. If you’ve ever gone to the dentist and gotten your lower jaw numbed up, this is the nerve responsible for this.
By keeping a safe distance away from the nerve, an altered sensation or nerve injury complication can be reduced…. But not completely eliminated. Complications can still occur with either method.
The nerve has several “tributaries” that are like in the fine fibers of a plant root system that you pull out. There is usually one main root and then thousands of little small rootlets. Most of the time as long as the main nerve is avoided, a nerve injury does not occur.
It can be a feeling of slight tingling all the way to feeling fully numb. Most are temporary and return within about a month to full sensation.
It is my belief that this procedure should really only be done by a very experienced dental implant provider.
The advantages of same-day extraction/ lower molar dental implant:
- Decreased cost
- Single visit procedure
- Time savings of 4-8 months
- No need for socket preservation bone graft ( usually still need a “void” bone graft though which is much more minor)
- One time on antibiotics
- One sedation
- Virtually eliminates bone loss from disuse atrophy
- Ability to place a very wide diameter implant
The disadvantage of same-day extraction/ lower molar dental implant:
- Slight increased risk of nerve injury
- Lack of implant to be able to achieve primary stability
- Often the implant needs to be buried and later and covered with a minor surgical/laser procedure
- The tooth extraction must go smoothly
- Centering of the implant can be more difficult if not impossible
Nerve injuries can be prevented by a skilled/experienced dentist, intravenous/intramuscular steroids, L PRF/PRP blood product, a 3-D scan planned procedure.
This patient’s case is really cool because her nerve is a mile away! The implant is one of the largest available… A 7.0 x 13 mm which obliterates most of the socket. Obliteration of most of the socket works well to gain stability of the implant, reducing the need for bone grafting, and gives molars a hefty base for a good emergence from the gum line. It also helps carry the high bite force is the back teeth which is important to prevent bone loss around an implant-peri-implantitis.
Obliteration of the socket is not a good idea in other areas of the mouth such as the upper front where the implant should be placed closer to your tongue and the implant ideally be smaller diameter. The rules are very different from each area of the mouth to another… what applies in one area of the mouth can be disastrous and other areas of the mouth!
In some extreme cases that I treat, the nerve is so shallow that I have to move it out of the way in order to put implants in the jaw. This is called a nerve repositioning/lateralization
Same day extraction and implant of lower molars is a wonderful procedure. In my hands, it is very predictable and I have been doing this for about 20 years now as of 2017. It is only intended for probably about 10% of molars. It can be done on the upper jaw as well as the lower jaw. During the surgery, if I feel like there is any increased risk, I will generally abandon the implant and only extract the tooth with a bone graft. You have to be flexible and change if needed for safety and predictability.
The red lines drawn into the 3-D scan indicates the placement of the nerve.
I hope this helps you understand this procedure. The images showed the 3-D scan before extraction and implant placement and another limited field 3-D scan taken after the implant.
Ramsey A. Amin, D.D.S.
Diplomate of the American Board of Oral Implantology /Implant Dentistry
Fellow-American Academy of Implant Dentistry