Dental Implant Surgery and Bone Grafting

A dental implant requires a sufficient volume of bone to be placed. Before placing a dental implant, the quantity and quality of the available bone must be assessed with imaging: a dental panoramic X-ray and a Cone Beam CT scan (3D imaging).

If the bone volume is sufficient (as in most cases), the implant can be placed. If the bone is too thin, it must be thickened by means of “bone expansion” or a “bone graft”, performed either at the time of implant placement or a few months beforehand. This is known as pre-implant surgery.

How long does an implant last?

Once the implant is in place and integrated, it will last for many years or even a lifetime. We do not yet have enough long-term data to state that an implant can last 30 years or more, but it is very likely. All that is required is good oral hygiene and an annual visit to your dentist for routine monitoring, to check that the crown is not loose and that there is no peri-implantitis (inflammation of the gum around the implant).

If left untreated, chronic peri-implantitis can lead to the loss of the implant in the long term, as repeated inflammation can gradually resorb the bone surrounding the implant

At Orthognathic Paris we use implants manufactured in France, from well-established brands with a proven track record of long-term reliability. For us, this is a guarantee of safety and long-term follow-up. The tooth (crown) attached to the implant may need to be re-fixed or replaced several years after placement. It must then be possible to intervene using quality parts and materials that are still on the market. The choice of implant system is therefore important.

Doctors Dujoncquoy, Ketoff and Laurian are qualified in bone surgery and implantology, and as maxillofacial surgeons they take a comprehensive view of the jaws. In implantology, they perform bone surgery, bone grafting and implant placement exclusively. They do not make dental prostheses. A referring dentist will fit the crown (the tooth placed on the implant).

Precise surgical technique and accurate implant positioning are guarantees of safety, and implant techniques must be perfectly mastered by your practitioner.

Your usual dentist — or, failing that, a colleague recommended by Orthognathic Paris — will fit the tooth (crown) once the implant is in place.

An implant can be placed once the bone and gum have healed, i.e. 3 months after the tooth has been extracted.

The surgical procedure is simple and painless. It is performed in the office under local anaesthesia, just like routine dental care, but under operating-room aseptic conditions. It can also be scheduled in a clinic under general anaesthesia if many implants need to be placed or if the patient feels anxious about undergoing surgery.

Once the implant has been placed, it is left in “hibernation” for 3 months. This is the time it needs to bond firmly to the bone, a process known as osseointegration. During this period the implant is not visible, as it sits beneath the gum (it can only be seen on an X-ray).

The implant is uncovered during a second session, referred to as the “second stage”. During this session, an abutment called a “healing screw” is attached to the implant. This abutment gives the dentist access to the implant so the tooth can be fitted. The final prosthesis or crown (the artificial tooth) is therefore fitted once the bone has consolidated and fused with the implant, i.e. 3 months after implant placement. In practice, the final tooth is thus fitted 6 months after the natural tooth was extracted or lost.

The success rate — that is, the osseointegration rate — is around 98 to 99% at Orthognathic Paris. This rate is achieved in non-smoking, non-diabetic patients when all stages and precautions are respected.
In some cases the crown (tooth) can be fitted immediately. However, this is not systematic and increases the risk of implant osseointegration failure.

Indications

To place an implant, the bone volume must be sufficient and the bone of good quality. This is assessed on a dental panoramic X-ray and a 3D examination called a Cone Beam CT scan.

If the volume of bone available to receive the implant is insufficient, bone augmentation by expansion or bone grafting is proposed. Bone powder such as Biobank®, or bone harvested from another part of the jaw, is then placed to thicken the available bone. Depending on the case, the implant will be placed either immediately or a few months after the graft, once the added bone has consolidated.

It is important that the neighbouring teeth and the gums are healthy, with no tooth mobility or gum bleeding (“periodontal disease” in medical terms), in order to limit the risk of osseointegration failure (the implant failing to bond to the bone). Indeed, in cases of untreated periodontal disease, oral bacteria may colonise the space around the implant.

Contraindications

Absolute contraindications are rare. Unfortunately, the following patients cannot receive a dental implant:

– patients who have received radiation therapy to the face during cancer treatment.
– patients with a condition carrying a high risk of infective endocarditis (heart valve recipients).
– patients who have taken a medication from the bisphosphonate group (an osteoporosis treatment prescribed by a rheumatologist)

Relative contraindications are more common:

– poor oral hygiene
– smoking
– untreated periodontal disease (bleeding gum disease)
– poorly controlled diabetes

Dental implants offer many advantages, as they restore the comfort of a natural tooth:

– Like the root of a natural tooth, the implant transmits chewing forces to the underlying bone, which helps maintain the volume and quality of the bone. Indeed, like a muscle, bone that is not stimulated gradually loses thickness, while stimulated bone retains its volume and density.

– A dental implant preserves the neighbouring teeth, unlike a bridge, which requires cutting into the enamel of the adjacent teeth to be fixed in place.

– The comfort is close to that of a natural tooth. Only the sensitivity to hot/cold and proprioception differ.

-The implant is perfectly solid and stable, which sets it apart from all other types of dental prosthesis, whatever their form.

The materials used are “biocompatible”. There is no allergy, and rejection is very rare (less than 1 to 3%). They are neutral and perfectly accepted by the human body, both biologically and mechanically.

In 1 to 3% of cases, the bonding process known as “osseointegration” does not occur. This failure is more common in smokers (tobacco use reduces implant success rates by 10-15%) and in diabetic patients.

However, in the event of failure, a new implant can be placed in the same site 3 months later, and in most cases this implant will integrate perfectly.

In the days following implant placement, moderate swelling of the cheek (oedema) or bruising may appear. However, this is not systematic and is controlled with paracetamol, anti-inflammatory medication and cold packs. Implant placement is very often less painful and better tolerated than tooth extraction. It is advisable to sleep with your head slightly elevated to prevent and limit the swelling or bruising that tends to appear the next day.

True complications are rare:

– local infection (peri-implantitis, abscess) or systemic infection. Tobacco use increases the risk of infection and of revision surgery.

– nerve injury with hypoaesthesia (numbness) of the lip (temporary or permanent), vascular injury, or sinus perforation. Fortunately, this is rare and is most often avoided thanks to the careful analysis of the X-rays performed before treatment. The experience of your maxillofacial surgeon or oral surgeon is a guarantee of safety. Orthognathic Paris offers on-site 3D radiological assessment (cone beam CT) at your first consultation.

Risks related to anaesthesia:

–Under local or general anaesthesia, an allergic reaction is in fact exceptional. The risks associated with general anaesthesia are explained in detail during the consultation with the anaesthetist. They are extremely low. Complications are very rare in healthy patients. General anaesthesia is no riskier when performed under proper conditions. Orthognathic Paris performs procedures in accredited clinics and selects the best anaesthetists for your safety.

Procedure under local anaesthesia:

The procedure is most often performed under local anaesthesia in the treatment room at Orthognathic Paris. It is painless and lasts 30 to 120 minutes. You should come without make-up, wash your face with a mild soap and use a mouthwash before the procedure. Wear dark clothing to avoid staining your clothes (Betadine).

First, the doctor settles you in, disinfects the skin around the mouth with Betadine and places sterile drapes. This preparation takes 10 minutes and gives you time to talk with the medical team if you have any final questions.

Once the local anaesthesia has taken effect, you will only feel the vibrations and pressure applied to the gum and can communicate with the team. There is no pain. Sensation in the gum returns 1 to 2 hours after the procedure.

Procedure under general anaesthesia:

If it reassures you, or if many implants need to be placed or a bone graft performed, the procedure can be carried out in a clinic under general anaesthesia. Doctors Dujoncquoy, Ketoff and Laurian operate at the Ambroise Paré – Hartmann private hospital group in Neuilly-sur-Seine and at the Clinique du Trocadéro in the 16th arrondissement of Paris.

In the days following implant placement, moderate swelling of the cheek (oedema) or bruising may appear. However, this is not systematic and is controlled with paracetamol, anti-inflammatory medication and cold packs. Implant placement is very often less painful and better tolerated than tooth extraction. It is advisable to sleep with your head slightly elevated to prevent and limit the swelling or bruising that tends to appear the next day.

After the procedure, pain is moderate and easily relieved with simple painkillers. Your diet is adapted for about a week, and activities will be slightly limited for the first few days. You can return to work the same afternoon or the next day. It is best to avoid sport for a week so as not to trigger further swelling or bleeding.

The final tooth, called the “crown”, will be fitted 3 to 4 months after implant placement. Your referring dentist — or, failing that, a practitioner recommended by the practice — will fit this tooth and attach it to the implant.

A few weeks beforehand, a further minor procedure, performed under local anaesthesia and known as uncovering or the “second stage”, is carried out in the office. This procedure is very light and takes 10 to 20 minutes. It allows a healing screw to be placed on the implant. A healing screw is a sort of snap fastener that prepares the gum by creating an access point so that your dentist can fit the crown (the new tooth).

Follow-up with your dentist (who will have fitted the crown) is sufficient to ensure the implant remains healthy. Once the implant is placed and osseointegrated, it will last for many years with regular follow-up and perfect oral hygiene (20 to 30 years or even more).

Typical case
In most cases, the implant can be placed 3 months after the tooth has been extracted. You will then need to wait 3 months before the implant can be used. This period of bone consolidation and bonding is known as the osseointegration period.

With a bone graft

When a prior bone graft is needed (sinus lift or onlay graft), it is sometimes necessary to wait 4 to 6 months before placing an implant, then another 3 months before fitting the final tooth.

For example, if the tooth or teeth have not yet been extracted, they must first be removed, followed by 3 months of bone healing. The bone must then be grafted to thicken it, followed by another 4 to 6 months of bone consolidation. The implant(s) can finally be placed, and another 3 months must pass before uncovering the implants and fitting the teeth (known as implant-supported crowns).

In these more complex cases, the process takes longer, and in total almost a year is needed for the teeth to be fully restored. However, in most cases the timeframe is much shorter.