People lose teeth all the time, either through trauma (when teeth are knocked out) or due to decay, gum disease or old age. Whatever the reason for losing your teeth, they need to be replaced, both for aesthetic and functional reasons. The most common treatments for missing teeth are either a denture or a fixed bridge. However, dental implants are now becoming a more popular treatment to replace missing teeth, as they provide a longer-term solution, slow down bone loss and preserve nearby healthy tooth tissue.

 

What is a dental implant?

A dental implant is an artificial substitute/replacement for the root portion of your natural tooth and is anchored into a pre-drilled socket in your jaw-bone to support a crown, bridge or secure a denture firmly in place. Implants are made from titanium, a material that is well tolerated by bone and integrates easily with bone tissue. During the placement of a dental implant, the goal is to achieve a close contact between the outer surface of the implant and the surrounding bone tissue so they can "fuse" together (osseointegration), creating a stable support for the new teeth.

 

Composition of dental implants

A typical implant consists of a titanium screw (resembling a tooth root) with a roughened or smooth surface. The majority of dental implants are made out of commercially pure titanium, which is available in 4 grades depending upon the amount of carbon and iron contained. More recently grade 5 titanium has increased in use. Grade 5 titanium, Titanium 6AL-4V, (signifying the Titanium alloy containing 6% Aluminium and 4% Vanadium alloy) is believed to offer similar osseointegration levels as commercially pure titanium. Ti-6Al-4V alloy offers better tensile strength and fracture resistance.

How is a dental implant placed?

Before any implants are placed, it is important for your dentist to assess the health of your teeth and gums. If there are any signs of gum disease or decay, these must first be treated. Thereafter, your treatment will be planned following several x-rays and, in some cases, a CT scan to assess that bone quality and check for nearby anatomical structures to avoid before any drilling. The procedure is usually carried out under local anaesthesia; IV sedation is sometimes used if it is a long procedure or the patient is very anxious.

The gum where the implant is to be placed is cut and lifted and a small hole is drilled in the jawbone at the precise location of the intended implant. The titanium implant is tightly fitted into this socket and the gum is stitched back over the implant. If there is insufficient bone material to accommodate the implant, a bone graft may be required, or the dentist may use smaller-sized mini implants if suitable.

Once the implant has been placed, it is left to heal and integrate with the jawbone for between six weeks to six months. The bone tissue will grow and anchor itself into the microscopic rough surface of the implant.

During this "healing period", patients are given temporary teeth (bridges) or continue to wear dentures. It is important that temporary teeth do not exert any force on the healing implant. After the healing period, the gum is again lifted and a post is attached to the implant with a temporary crown. Four to six weeks later, when the surrounding gum tissue has matured, the final permanent restoration can be fitted to the implant.

 

The advantages of dental implants over dentures and bridges:

• Reduced bone loss
  Normally, the bone tissue surrounding the root of your tooth is maintained by your body's natural renewal process. However, if you loose a tooth, you will be left with a hole where your tooth root used to be and the bone around this area will slowly begin to disappear (atrophy) which may change the shape of your jaw. A dental implant placed in that area can actually stimulate bone growth and production, preventing loss of valuable bone structure. In some patients where bone loss is substantial, a bone graft may be required before placing a dental implant. Bone loss is a problem for people who have dentures, and as the shape of the jaw slowly changes, the dentures need to be adjusted or re-made to fit the new shape of the jaw. Bone loss can also make a person look older, since the area around the mouth can sag as bone is lost
• Improved function
  Once dental implants are fully integrated into your jaw, they function just as well as your own natural teeth: you can eat the foods you want and speak with complete confidence. With dentures, eating hard foods such as an apple can be a problem: either the dentures come loose or patients cannot withstand the hard biting forces as they cause pain in the gums. Irritation and inflammation of the gums is a common problem amongst denture patients. Dentures can be supported by implants or mini-implants, which will greatly improve function, enabling patients to eat the foods they want with complete confidence and not having to worry about bone loss and loose dentures falling out.
• Improved dental hygiene
  Unlike bridges and dentures, which require special cleaning instructions and extra attention, dental implants just need regular brushing, flossing and dental hygiene appointments, just like your natural teeth.
• No need to drill or remove any healthy tooth structure
  When replacing missing teeth with dental bridges, the teeth adjacent to the gap need to be prepared and healthy tooth structure is removed to accommodate a crown or bridge abutment to fit over the top of the tooth. In the future, if one of the supporting teeth is damaged, the entire bridge restoration will also be compromised, whereas with an implant, the restoration is independent of any of your other teeth. By replacing lost teeth with an implant, no support is required of the adjacent teeth, and your natural teeth do not need to be prepared or altered in any way
• Better aesthetics
  If done correctly, a dental implant should be indistinguishable from your surrounding natural teeth. Dentures can come loose and look unnatural if they do not blend with your gums, and some bridges and dentures have unsightly metal clasps to hold them in place. Dental implants provide a much better cosmetic and functional end result.

 

How many teeth can a dental implant support?

Traditionally, an implant placed into your bone supports a single crown and this is know as a "single tooth implant". However, if you have several missing teeth, you do not necessarily need an implant for every missing tooth: one implant can support several teeth via a bridge or denture. The number of implants required depends on the volume and density of bone tissue available at each implant site. Often, smaller-sized "mini implants" are used to secure dentures in place.

In the case of full-mouth reconstructions, where an arch of several teeth (10+) needs to be supported in either the upper or lower jaw, a minimum of five to eight implants in each jaw would be required. The exact number of implants needed would depend on the individual case and your implant surgeon would be able to advise you on the best solution after a thorough examination and assessment.

 

Am I a suitable candidate for dental implants?

 

Dental implants can be placed in patients of any age (with fully developed jawbones), provided that they have a sufficient quantity and quality of bone tissue available. Most healthy individuals that maintain a good oral hygiene program are suitable candidates for dental implants. Circumstances where implants may not be suitable, or situations that have an increased risk of implant failure, include:

• Heavy smoking - this slows down and hinders the healing process.
• Excessive alcohol intake - disrupts healing of the gums. 
• Periodontal gum disease - all active gum disease must be treated prior to any implant procedure to ensure the long-term success of any treatment. Periodontal disease is a major cause of bone loss, which would hinder the success of any implant procedure.
• Immuno-compromised individuals (steroids, auto-immune disease, patients undergoing radiation treatment).
• Teeth grinders (bruxism) - a night-time splint can be given to treat this.

 

How will I know if I have enough bone for implants?

 

Using a combination of dental X-rays and a CT scan, your bone density and volume can be assessed, and information about nearby anatomical structures to avoid (such as nerves) can also be gathered.

 

What if I don't have enough bone for dental implants?

 

The alternatives for replacing missing teeth include dentures and bridges. However, there are various bone-grafting and tissue-regeneration procedures that can be carried out to enable treatment with dental implants:

Sinus augmentation (sinus lift) - if you need to replace missing teeth at the back of the upper jaw, a sinus augmentation, whereby new bone in the sinus is created, can increase the height of the bone available for the placement of implants in this area.

Bone grafting - this is where a piece of bone is taken from somewhere else and secured over an area that is deficient in bone; over time, the newly placed bone will fuse with the underlying bone creating a better environment for an implant to be placed.

 

Where can bone be taken from for the graft?

 

The best source of bone for your graft is your own bone tissue from elsewhere in your body. Bone can be grafted from the chin, the back of the lower jaw, the hip and the tibia. Bone taken from your own body is the most viable and has faster healing times when compared to alternatives. In many cases, a combination of artificial bone substitutes and your natural bone is used. In any bone grafting procedure, the grafted bone provides an anchor and stimulus for the existing bone to grow onto, eventually providing an environment suitable for the placement of implants.

 

How long do dental implants last?

 

Dental implants have been used for over 30 years to replace missing teeth and they can last a lifetime depending on how well you look after them. Like any other restoration, your implant-supported teeth can still be damaged by trauma and affected by gum disease and poor oral hygiene.

 

Deciding on treatment

 

Dental implants have a high success rate. The surgery is commonly performed and is generally safe. However, in order to make an informed decision and give your consent, you need to be aware of the possible side-effects and the risk of complications of this procedure.

 

Side-effects

 

Side-effects are the unwanted but mostly temporary effects of a procedure. Examples of side-effects include some swelling and discomfort around the implant area. If you have any discomfort, take an over-the-counter painkiller such as paracetamol or ibuprofen. Follow the instructions in the patient information leaflet that comes with the medicine and ask your pharmacist for advice about whether it's suitable for your individual circumstances.

 

Complications

 

The chance of complications depends on the type of procedure you are having and factors such as your general health. Complications can occur during or after the procedure. Most people aren't affected. The complications of any surgical procedure can include an unexpected reaction to the anaesthetic or infection. You are likely to be prescribed antibiotics and an antiseptic mouthwash to reduce the risk of your implant becoming infected.

Your lower jaw contains nerves which supply feeling to your tongue, chin, lower lip and lower teeth. In a small number of people, the nerves in the lower jaw can become bruised during implant surgery. This may cause a tingling or numb feeling in your tongue, chin or lip. This is usually temporary, but in a small number of people this altered sensation may be permanent.

On very rare occasions, the jawbone doesn't fuse with the implant properly and the implant may become loose. If this happens your dentist will need to remove the failed implant and wait until the bone has healed before attempting to place another implant.

Most implants are very successful, but the crowns, bridges and dentures that the implants support can be damaged just like normal teeth - for example, as a result of an accident, break or chip. The crowns, bridges or dentures are generally easily replaced, providing the implant underneath isn't damaged.

Implants can last for many years but maintaining good oral hygiene is vital. To help maintain your implants you may have to spend more time than you did in the past thoroughly brushing and flossing your teeth. Your dentist will give you specific advice on caring for your implants. He or she will ask you to attend regular check-ups, and will usually take X-ray images each year to check your implants are still secure.

 

Type of dental implants:

1. Root Form Implants

Also known as 'Endosteal' or 'Endosseous implants': this type of implant involves the insertion of the implant directly into the jawbone. This is the most popular type of implant and comes in two forms: cylinder and screw.

The implants can hold a single tooth or several artificial teeth. They are an ideal choice for those patients who have removable dentures or a bridge.

The procedure involves the dentist making an incision in your gums in order to expose the jawbone. He or she will insert the implant and close the incision with tiny stitches.

You are asked to wait for 3 to 6 months to allow healing or osseointegration to take place. In that time, the implant will have fused with the bone of your jaw.

Once done so, you will return for a second procedure in which the incision is opened up to allow access to the implant. Your dentist will then fit a special attachment called an abutment to the end of the implant.

This forms a strong, solid unit which is then ready for the replacement teeth.

These are considered to be the easiest and most versatile form of implant. The implant itself is constructed of titanium and lends itself well to fusion with living bone.

The most suitable candidates for this implant are those with a wide, deep jawbone. If your jawbone is small or thin then don't worry; root form implants are still an option although you will require a bone graft to build up the jawbone area.

If your dentist feels that your jawbone is far too narrow and bone grafting is not an option then he or she may recommend a plate form implant.

There is another type of endosteal implant called 'endosseous blade implants'. These have been in existence for some time now and take the form of long, flat pieces of metal which are inserted via a channel, into the bone.

These metal implants can be bent or manipulated in a variety of ways to fit an individual patient's anatomy.

However, they have been reported as having a high failure rate and because of this, are not generally recommended.

 

2. Plate Form Implants

 

This takes the form of a narrow metal plate which is inserted into the jawbone. Your dentist will expose the area of your jawbone for treatment before preparing the bone to receive the implant. He or she will make a series of incisions in the gums before inserting the implants. The number of incisions made will depend on the number of implants.

The implants are inserted and the incisions closed with tiny stitches.

The dentist will advise you to wait for a set period of time to allow osseointegration to take place. However, in some cases you can have restorations directly after the implant procedure. This is known as 'immediate loading'.

If your jawbone is not deep or wide enough to support root form or plate form implants, and there is too much bone loss, then consider having a subperiosteal implant.

 

3. Subperiosteal Implants

 

This implant takes the form of a lightweight framework which is designed to your anatomical requirements. In other words, the size and shape of your mouth.

This framework is inserted underneath the gum tissue and sits over the jawbone, acting as a series of tooth roots. This enables it to act as an 'anchor' for the subsequent restorations. The restorations are attached to this implant via a series of posts which protrude through the gum tissue. This is a custom made implant which is produced in two ways: Single surgery method: this involves the dentist arranging a special CAT scan of your jawbone. The data from this scan along with advanced computer modelling software will be used to construct a model of your jawbone. This model is then passed to a dental laboratory that will use this to design the subperiosteal implant that will fit onto your jawbone. The procedure involves the dentist exposing your jawbone and placing the implant on top before closing the incision with tiny stitches.

This is ready for the placement of the restorations.

1. Dual surgery method: this surgical procedure involves the dentist exposing your jawbone, under anaesthesia, in order to take an 'impression'. He or she will use special materials to do so.

The model is then passed to a dental laboratory who will construct a subperiosteal implant, which is specially designed to fit your jaw and no one else's.

The dentist will carry out a second procedure in which he/she will again, expose your jawbone and place the implant. This sits on top of your jawbone, under the gums.

The incisions are closed with small stitches. Restorations can now be put in place.

 

4. Mini Implants

 

The mini implant is as the name says: it is smaller than the normal sized implant and were originally designed as a temporary measure. The idea was that these would be inserted as a temporary implant and then removed at a later date, replaced by the full sized implant.

However, they were found to be a useful type of implant in their own right. They tend to work best as a replacement for small teeth or incisors.

They are placed in the jawbone but because of their limited height do not fuse easily with the jaw bone (osseointegration). But, they do last a long time and tend to be used as a means of stabilising the lower denture, especially in older patients.

If a patient's x-ray shows bone loss then they normally require a bone graft before the implant is inserted. However, they may be reluctant to do so, either for reasons of age or health.

If this is the case then a mini dental implant may be an acceptable choice of implant. It is a solid although smaller form of implant and does not require the patient to undergo a bone graft beforehand.

The mini implant is comprised of a slim titanium rod that has a retaining fixture which can be incorporated into a denture. The head of the implant is shaped like a ball and the retaining attachment contains a rubber 'O-ring' that acts like a socket.

This holds a denture in place by means of the rubber 'O-ring' which snaps over the ball at the top of the implant. This enables the denture to rest nicely on top of the gum tissue.

 

These are fast becoming a popular choice of implant for many patients who are uncomfortable with the thought of a full implant or are worried about the cost!

 

Type of dental implant works:

1. Single Tooth Dental Implants

You may have lost a single tooth as a result of an accident or injury. This can be replaced with an implant and in fact, having a dental implant in between your natural teeth is the most successful dental procedure. Success rates are nearly 100% perfect.

A single tooth implant does not affect your other teeth, looks better and is easy to keep clean. It is kept clean in exactly the same way as your other teeth.

If your jawbone is not deep or strong enough for an implant then a bone graft will be required.

Single tooth implants can be carried out on both front and back teeth. Mini implants can be used although some dentists prefer the normal, full sized ones.

The procedure is as normal: the dentist will make a tiny incision in your gum in order to access your jawbone. He or she will then drill a small hole in this bone before inserting the implant. The implant will look like a small metal rod and is either cylinder or screw shaped.

This is inserted into the jaw. The incision is closed and given time to heal. This is usually a period of 3 to 6 months. During that time the implant will fuse with the jawbone in a process called osseointegration. A temporary tooth or crown will be fitted during that time, purely for cosmetic reasons.

Once this has happened, a second procedure will be carried out. The dentist will open up the original wound before fixing a small attachment or abutment to the implant. This will enable him/her to fasten an artificial tooth or restoration to the abutment.

This is usually done in two stages although there is the option of having this done all in one go, known as 'immediate loading'.

 

2. Few or Several Teeth (partially edentulous)

 

 

This section is aimed at those patients who are missing a few or several teeth. The technical term for this is 'partially edentulous'. If you have lost a few teeth, either as a result of an accident or an injury then you are basically looking at a crown and bridge implant system.

If, however, you are missing quite a few teeth then you could be looking at extensive dental work. This type of treatment will involve implants but will also include bone/sinus grafts and quite possibly some major reconstructive work.

 

Are you missing just a few teeth?

 

If so then there are several different ways of performing this treatment although they all involve attaching crowns or a bridge onto an implant. These can be cemented or screwed onto the implants.

Crowns and bridges are constructed from a variety of materials such as ceramic, porcelain or a combination of metal and porcelain.

The traditional crown and bridge system was a short term answer to the problem of missing teeth but required the dentist to file down a couple of healthy teeth to act as 'posts' to support the bridge.

Another issue is that of bone loss. The traditional crown and bridge system does not prevent bone loss. Bone loss tends to happen when a tooth or teeth are lost and are not replaced. The jawbone becomes thinner and less dense and results in a sunken cheeked appearance.

The only way to prevent this is to combine the crown and bridge system with dental implants. The implants stimulate the bone cells within the jaw and stop any bone loss.

This procedure can be performed as part or all of the following:

• Implant crown and bridge
• Major maxillary reconstruction
• Major reconstruction
• Replacement of a failed blade implant
• Total dental care

 

Implant crown and bridge

 

This procedure involves several stages which start with the initial diagnosis, x-ray and wax impression of the patient's jaw. Once this has been completed then the next stage is that of the insertion of the implant itself.

Once sufficient time has elapsed for osseointegration then the final stage is that of the restorations. The patient will have had temporary restorations during this time, but once the implants have completely fused then they are ready for the final restorations.

A bridge is required to span the gap left by the missing teeth along with laboratory constructed crowns.

 

Major Maxillary Reconstruction

 

This is an extensive procedure, designed to treat problems with teeth in the upper jaw or maxilla. If you have missing maxillary teeth, for whatever the reason then this procedure is an option.

This procedure is carried out on those patients who have been diagnosed with a tumour or have a maxilla related injury such temporomandibular disorder.

The procedure involves implants, a cast and restorations.

 

Major reconstruction

 

The same rules apply as above. The patient can be looking at the insertion of several implants, bone augmentation (possible) and/or sinus lift, and temporary restorations before the placement of the final restorations.

It can involve either the upper or lower jaw, or both.

 

Replacement of Failing Blade Implant

 

A blade implant or plate form implant is a type of endosteal implant (implanted into the bone) which is less commonly used than the root form implant. It consists of a flat piece of metal (blade) with two prongs on one side of this metal. It is inserted into the jaw in such a way to support a bridge or crowns.

These along with other types of implants enjoy a high degree of success, usually around the 95% mark. But, failure can happen in a tiny minority of cases. This is usually due to a failure to fuse or 'osseointegrate' with the bone, inflammation (peri-implantitis) or fracture. Sometimes, implants can move around or shift out of position.

Whatever the reason an implant which is said to have 'failed', needs to be removed and replaced with a new one.

In this scenario, the failing blade implant will be removed and replaced by root form implants as part of a two stage process. The first stage will involve the removal of the defective implant and the second stage will be the placement of the new teeth or restorations.

 

Total Dental Care

 

This is the 'full works' in regard to dental treatment. It involves implants, crown and bridge restorations and porcelain veneers (also known as laminates).

This comprehensive treatment will involve a sinus lift plus a cast for the crown and bridge restorations. The veneers (laminates) are wafer thin shells, comprised of porcelain or ceramic, which are fitted over the front of the teeth in order to improve their appearance.

If your teeth are stained or damaged then consider this as an option.

 

3. No Teeth (fully edentulous)

 

Edentulous is a dental term, used to describe a state in which a patient has no teeth at all. This may sound strange but there are a great many people who do not have any teeth, either as a result of an accident or illness.

If you are in this position then dentures are often the only solution. This means having to use a messy 'glue' to fix their dentures in place which can be awkward and off-putting.

Dentures are a tried and tested answer to the problem of missing teeth but they are not without their problems which include the tendency to become loose, soreness and irritation.

These problems will resolve themselves over time as you become used to wearing dentures but there are some patients who never come to terms with denture wear. For that group of patients, dental implants are the answer.

There are several treatment options available to the patient:

• Crown and bridge restoration
• Fixed/detached restoration
• Implant overdenture
• Mini implant overdenture

 

Crown and bridge restoration

 

This involves the use of restorations or crowns (artificial teeth) and a special bridge (a temporary denture). The crowns are attached to this bridge and are a permanent fixture unlike the usual removable restorations.

Fixed restorations (teeth) are more realistic looking than the removable type of restoration but are also more expensive.

And, they are more difficult to clean and generally, care for.

A crown and bridge restoration can be carried out as part of a major reconstruction or as a means of converting from a removable restoration to a fixed restoration.

This is an extensive process which includes initial diagnostics, the taking of an impression of your jaw - for purposes of casting, and the insertion of the implants. The second stage includes the fitting of the abutments and the final replacement teeth (crowns and bridge).

Fixed/Detachable Restorations

 

These are as the name says: they are a type of restoration which is fixed in place by a series of screws. It is a permanent fixture and can only be removed by your dentist.

These tend to appeal to those patients who find dentures to be awkward or plain unattractive.

Fixed restorations are harder to keep clean than removable ones.

This restoration takes the form of a metal framework, dentures (teeth) and an acrylic resin.

 

Implant overdenture

 

This form of treatment combines dental implants with an overdenture and so may appeal to those patients who want a cheaper yet effective dental treatment.

An overdenture is made to fit over existing tooth roots or dental implants. This is supported by the natural tissue of your mouth and is designed to work as a working alternative to natural teeth.

One advantage of this over conventional dentures is that this stays firmly in place. This means no risk of 'slippage' or any other problems associated with a conventional denture; plus it is easy to look after.

It is also cheaper than other types of hybrid restorations such as crown and bridge restorations.

 

 

Mini Implant Overdenture

 

This is very similar to the normal sized overdentures: the only difference being that mini dental implants are used instead. Mini implants are cheaper than the standard sized ones and easier to insert but have us

ually been seen as a temporary measure.

But, they have proved to be useful in situations where patients don't want the full implant, are unable to pay for a full implant or just need something to secure a loose denture.

There are still ongoing discussions about mini implants as compared to the normal, full sized implants. Some sources view them as a suitable form of treatment if there are no other choices, or if normal implants are not an option.

Other sources see them as providing a good, solid foundation for bridges, crowns and overdentures.