Dental Implant & Preprosthetic Surgery

What are implants?

In medicine, implants are used to replace and repair natural structures lost to disease. In dentistry, Dental implants are used to replace teeth.
Generally, dental implants consists of two portions, the portion replacing the root portion of the tooth (the implant fixture) and the portion replacing the crown portion of the tooth (the artificial crown).

Am I suitable for dental implants.

The best person to advise a patient on whether or not he or she is suitable to have dental implants is the dentist. This is because there are many factors to consider. The general health of the individual is important. Diabetics must be well controlled if they were to consider implants. As dental implant therapy requires several surgeries, albeit small, any medical conditions which may lead to complications related to the surgery must firstly be treated and put under control. A person's social habit may also jeopardize the implant. If the patient is a smoker, it will affect the implant's lifespan. Local factors like the amount and quality of bone where the implant is to be placed, as well as occlusion (biting position and forces) must be accurately assessed. The oral hygiene of the patient is of utmost importance. Healthy disease free gums are essential for the success of any implant therapy. People with implants must keep them clean and should return regularly to their dentists for checkups so that any problems which may compromise the lifespan of the implant may be corrected early.

What does implant therapy involve?

The standard protocol of implant replacement therapy involves the following steps:

1) Examination and Diagnosis

At this stage, the doctors will assess the patient for suitability for implant therapy. This will include a general examination, some investigations like Xrays or CT Scans. There may also be some moulds taken to assess the positions and number of implants required.

2) Implant placement surgery

If there is inadequate bone around the implant site, the surgeon will decide if there is a need to graft (add) bone to the area. There are many bone grafting materials to choose from. The best bone is autogenous (patient's own) bone. It is usually taken from another site of the jaw or even the hip bone. If there is enough bone, the implant fixture(screw) may be placed directly onto the bone. There is a healing period for the implant to osseointegrate (bond with the bone). This healing period may take up to six months. During this period, there is nothing seen in the mouth and the patient may continue wearing his/her denture over the surgical site.

3) Implant uncovering surgery

At this stage, there will be a minor procedure to expose the implant. After this surgery, there will be metal buttons' protruding from the gums. The positions of the buttons will be the spots where the implant tooth will be built upon. After a few weeks of healing, fabrication of the crowns of the implant tooth may begin.

4) Restorative phase

During this period, there will be several visits to the surgeon as there are a few steps involved in the fabrication of the crown portion of the implant. This is also the last stage of the implant therapy. The patient will leave the clinic with a brand new set of permanent' teeth.

Variations to the standard protocol

Immediate implants?
Although the standard protocol applies to most cases, there many variations to the protocol. There are immediate implants where the patient may be able to have implant teeth fabricated and issued within a week or even a day. These indications are very specific and the surgeon will be able to advice on the suitability of such cases on an individual basis. This option is gaining popularity as many patients prefer to have their implants restored as early as possible. However, patients must understand that this protocol requires some criteria to be satisfied in order to enjoy good success rates.

Zygomaticus implants?

These implants are very advanced implants and indications are absolutely strict. It involves the placement of long implants which engage the zygomatic bone from within the maxillary antrum/sinus in the upper jaw. These implants are also complemented by up to four normal implants to the front of the maxilla. This procedure requires extreme precision and close coordination between the surgeons and the restorative dentist. Not all patients are suitable for this treatment option.

How long do implants last?

The success of implant therapy depends on many factors. Referring to the selection criteria for suitable patients, it becomes obvious that factors such as diabetes (if poorly controlled) and smoking does decrease the success rate of implant treatment.
Oral hygiene plays a very major role in implant success. A poorly maintained implant will suffer from gradual bone loss and may be loosened and unusable after a few years. Meticulous maintenance of the implants and scheduled visits to the surgeon is essential to spot early problems and remedy them before the problems become untreatable.
The correct usages of the implant tooth/teeth are important. Implant crowns are made of metal and ceramics. They are able to take great compression forces but not shearing or lateral forces. As such, the manner in which the implant is used will determine the lifespan. Patients are usually advised on their diet after implant therapy.
When implants fail, it will manifest as pain, discharge around the implants and looseness of the implant. Failure can happen at different levels. It may be a mechanical failure of the components or a biological failure of osseointegration.
The surgeon will be able to assess the problem and can recommend remedial treatment. Sometimes, this will include removal of the entire implant fixture. However, the same bone site may receive another implant after healing and the entire treatment may be repeated with no harm to the neighbouring teeth
If well maintained, an implant may last for more than twenty years. Success rates can be as high as 99%.