“What about them implant things?”

Today’s blog post is going to be an overview of dental implants. I won’t go too much into specifics of types, the science etc because it’s a bit irrelevant, many boffins in many Scandinavian labs have done all the work for us and also, I  have no idea what half of the publications related to said science are on about.

I will split the topic into 2, what they are and what they can be used fo and in whom, then will do a part 2 explaining what is involved in their placement, aftercare, lifespan etc so stay tuned for that!

Shall we begin? Good.

What are they?

The Association of Dental Implantology UK (ADI) define implants as “a substitute for a natural root and commonly it is screw or cylinder shaped”. The actual object called the "dental implant" refers to the bit that is in the bone. Other components can be added/ attached to make the implant functional, for example, something called an abutment can be screwed on top, which passes through the gum and allows prosthetic (fake) teeth to be attached. See helpful pictures below.

Why would you need them?

So, you find yourself in the situation where you are either already missing, or are about to lose either 1 tooth e.g. you got caught in a drunken brawl, you ate too many sweets or in fact several teeth, for instance due to dental disease or following trauma (often horse related) or after removal of tumours etc. 

Placement of implants after cancer surgery is much more involved because not only are the teeth often missing, but the disgusting thing takes most of either one or both jaw bones with it and so extensive rebuilding is necessary before implants can be placed therefore making it much more complicated and beyond my limited realm of knowledge and so we shall stick to the “I haven’t brushed my teeth for 20 years and would now like you to fix it for me” causes of tooth loss.

How do they work and what can they be used for?

This seems a fairly obvious question however there is a lot of confusion of what implants can do. They are the closest thing to a natural tooth that can be provided by a dentist however they have several limitations. They can be used to replace individual lost teeth, in the majority of cases this is front teeth.

There is a lot of panic about losing and replacing of back teeth. Obviously if you have one of those smiles that shows every single tooth in your mouth and beyond, or have one of those laughs where you can see your epiglottis then the concern about missing a tooth is understandable. Fortunately most people don’t have this problem and so if you lose a molar tooth, there is actually no need to replace it. Especially with something that costs a minimum of 2 grand.

***As a side note if you come across one of those adverts promising 15 implants for the cost of a Mars bar, I would stay well away. I would consider dental implants in the same way you would think about other implants – hip replacements, breast implants etc and if you wouldn’t go to a rat infested converted house to have those done on the cheap, then you shouldn’t have your teeth done in the same situation. I think because they’re teeth people believe that the same standards are care aren’t necessary, only takes 5 years to be a dentist and that, surely my beautician could do it? The answer is no. Obviously. Mainly because if something goes wrong, its’ your jaw and your head. There is limited bone and so any infection caused by dodgy placement (bearing in mind there is a risk of infection even under pristine surgical conditions and a skilled operator) means that you are at risk of losing significant portions of your jaw bone and at this point, we can’t fix it. Mini rant over. Let’s continue

The only feasible reason for replacing a missing back tooth is to stop over-eruption of the opposing tooth, that is to say when the tooth that is biting against the one that is lost grows out of the gum and into the space. It is a very rare case that a tooth in the mouth ONLY comes into contact with 1 other tooth when biting, usually they touch 2 or 3 depending how you bite and for this reason usually over-eruption won’t occur.

Let’s see if a picture helps…

 Over-eruption means that the bit of the tooth that usually sits under the gum line is now exposed to the mouth. In terms of potential consequences this can look a bit unsightly, but again it would depend on your smile and what is shown. If you only see it in the mirror when you’re looking at a demented angle whilst stretching out your cheek then it really won’t affect your life. The other potential problem is that the bit of tooth under the gum line doesn’t have the protective enamel layer and so can be sensitive but again this can be dealt with in other ways that doesn’t involve damaging any teeth by placing bridges or burning a hole in your wallet.

Implants can also be used to replace multiple teeth either as a way of acting as an anchor for a bridge, which thus will replace 2 teeth, or to have several implants to more effectively hold in a denture.

Implants are NOT used to replace every tooth in the mouth. If you have no teeth left, then you need a denture. End of. The stabilisation of a denture CAN be improved by implants.

I emphasise word can for the following reasons. Fortunately some clever people have done some research so I can insert that now…

Assunção et al found that “Although the stability of the mandibular (lower) implant-retained denture was enhanced compared to a conventional denture, the quality of life and satisfaction levels were similar for both the groups.” i.e. the groups of people with and without implants felt equally happy (or in fact unhappy) with their dentures.

Allen et al found that “Subjects who received implants that replaced conventional complete dentures reported significant improvement after treatment, as did subjects who requested conventional replacement dentures” i.e. simply having some sort of denture was more important/life changing than having implants to hold a denture in.

Basically, implants are not the be all and end all of tooth replacement.

So, that’s what they can be used for, how about what they actually are.

	For this reason, one of the risks of having implants placed is that if they fail, it is often due to damage to the bone surrounding the implant rather than the implant itself as the metal implant is far stronger than the bone it is encased in and in a fight, the weaker one loses. This is the same reason by post crowns fail – the post is stronger than the tooth it is stuck in, so rather than the post breaking, the tooth does instead. I will go into this more in the second part of this blog. Multiple implants to stabilise dentures work in a similar way but takes slightly more careful assessment as it is not a case of plonking an implant in where a tooth has come out. The position and placement of the implants in order to best retain a denture has to be worked out and will be different in every person.

  

As you can see from the above pictures, this particular patient has 4 implants. They can be left as the implants alone onto which the denture clips. Or the implants can be connected with a bar and the denture clips onto this. Sometimes fewer implants will be placed etc etc and this will all be decided by the implant-surgeon.

Below you can see how denture clips into the implants. This particular case does not have a bar whereas the one above does.

In the final bit of this blog post I will quickly go over who is not suitable for implants. Of course you will most likely be able to track down someone somewhere who will place the implants without asking questions. As I said earlier, if you like taking risks with your health and in fact life, go ahead. If not, go to someone who actually knows what they’re doing who will tell you the following.

Contraindication	Why
Smoking	Smoking reduces blood circulation in the mouth and suppresses the immune response in the mouth, what this means is that healing in smokers is crap. As healing is necessary for implants to work (as the bone needs to fuse around the implants) it is highly reduced in smokers. Thus infections and fusing of the implants is highly reduced. You may also experience more pain from the procedure and this pain could last for longer. It is also possible that the implant will never heal and this could leave you in constant pain, resulting in the removal of the implant. Finally, long-term smoking affects how dense the bone is meaning that finding suitable strong enough jaw bone is more difficult.
High alcohol use	Alcohol, like smoking, seriously affects healing and thus can lead to implant failure.
Gum disease	Number one, gum disease can destroy bone. No bone = no implants. Simples. Even if enough bone is found to put an implant in the first place, gum disease will inevitably lead to its failure through the same bone destruction.
Clenching and Grinding teeth	As briefly mentioned above, the implants are not natural shock absorbers like teeth are and so any excess force, like clenching and grinding of the teeth, can damage the crown on top of the implant and potentially the base of the implant as well just as clenching and grinding can damage natural roots.
Weakened Immune System	Implant placement requires an operation. While it is a relatively minor operation, any reduction to the immune system normal responses can lead to infection. Weakened immunity can occur naturally with age, due to chemotherapy, AIDs, cancer, steroid therapy, medication following transplants, Diabetes etc. Of course this will be discussed during consultation and whilst having these conditions/taking those meds does not completely rule you out from having implants, certain modifications to treatment might have to be made
Bisphosphonate Medication	Bisphosphonates are a type of medication taken mostly for osteoporosis, but also for conditions such as Paget’s disease, bone cancers, metastatic cancers. They basically alter the way that bone heals and for that reason, anything that “damages” the bone in patients taking these medications can lead to devastating infection.
Unsuitable bone	For example very thin bone. While it is possible to bone graft, move the sinus to create more space etc this is far more extensive treatment. This is particularly irritating when people come in, you tell them they need a denture, or that we cannot fix their dentures to make them like normal teeth. The automatic response of the patient being “what about them implants?”. If you have enough teeth missing to need a denture, you need a denture. If your dentures drop out because you have no bone left, you can’t have implants without a whole tonne of extra surgery.

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So that’s all for today folks!!!

Feel free to ask any questions and remember to check back in a couple of weeks for details of exactly what is involved in implant placement and sadly, things that can go wrong!!

References and that..

Allen, McMillan, Walshaw,  A patient-based assessment of implant-stabilized and conventional complete dentures The Journal of Prosthetic Dentistr Volume 85, Issue 2, February 2001, Pages 141–147

Assunção WG, Zardo GG, Delben JA, Barão VA. Comparing the efficacy of mandibular implant-retained overdentures and conventional dentures among elderly edentulous patients: satisfaction and quality of life. Gerodontology. 2007 Dec;24(4):235-8.

Chee & Jivraj  Failures in implant dentistry British Dental Journal 202, 123 - 129 (2007) 

http://www.adi.org.uk/public/implant/whatis.htm

http://www.clydedental.com/dental-implants-glasgow.html

http://www.philipfriel.com/implant-retained-dentures-gallery.html

http://kumarandentalclinic.com/Missing%20Tooth.htm
http://www.philipfriel.com/implant-retained-dentures-gallery.html

http://en.wikipedia.org/wiki/Dental_implant

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