There are basically three parts to an implant restoration
- The titanium ‘root’ piece which gets placed in the bone. Over time, bone grows up to and around the implant ‘root’. This process is called ‘osseointegration’ and provides a biologic fixation with the bone.
- The abutment is the component which is connected to the implant ‘root’ once the implant root has integrated.
- The definitive porcelain implant crown/tooth, which is made in a laboratory and fitted to the implant abutment.
Sometimes it is possible to connect a temporary or transitional crown to the implant ‘root’, at the implant insertion appointment. This can only be done if a number of important ‘clinical checkpoints’ are passed at this insertion appointment. It is not possible to accurately assess these conditions beforehand, only at the time of the implant ‘root’ placement appointment.
The time required for osseointegration can vary from patient to patient, but a guideline of eight to twelve weeks would be reasonably common.
Implants are used to:
- Replace a single missing tooth.
- Support a bridge which spans the gap of more than one missing tooth.
- Help full denture wearers who find the mobility of their dentures intolerable. In this case the placement of a few strategically placed implants in the jaw can act as supports with ‘poppers’ on top which ‘snap’ into corresponding receptors on the underside of the denture. While this may not totally eliminate movement of the denture, it certainly reduces it to an acceptable level, where the denture remains stable under function, allowing greater confidence during chewing and speech and improved patient satisfaction.
- Replace full dentures with a fixed restoration. This is for patients with no teeth who wear full dentures and who want a totally stable, fixed restoration that is not a denture. It is often possible in the presence of sufficient bone, to have multiple implants placed to retain bridgework, thus avoiding a removable denture.
Success rates of 98% are achievable in the hands of properly trained and skilled dentists. When properly planned and executed, dental implants are a safe and predictable treatment modality and are often the preferred alternative to conventional tooth supported bridgework and dentures. When an implant is used to replace a missing tooth rather than a conventional bridge or an adhesive bridge, the teeth either side of the gap are not needed to retain the replacement tooth, i.e. your own teeth remain untouched. Thus it is a minimally invasive means of replacing a missing tooth.
How ‘easy’ or straight forward an implant case is for a particular patient depends on the quality and quantity of bone available into which an implant can be placed. To this end a CAT scan is often necessary to determine baseline height and width of bone levels. This information can be garnered in-house at S.E.D.S, as we have available on the premises,a state of the art Serona Galileos, digital low-dose radiation CAT scan machine. This enables us to give you very comprehensive treatment proposals early in the consultation process.
Once integration has sucessfully occurred, the titanium root component of the implant can be considered a longterm root support and has the potential to last a lifetime. The implant retained porcelain crown or ‘tooth’ on top of the implant root is subject to wear and tear and can be expected to need replacement over time. This time interval varies from patient to patient and is influenced by many factors such as:
- Are the restorations being regularly cleaned and maintained during patient home-care and as part of a regular dental recall?
- Are there enough other teeth of suitable quality in the mouth to help share the chewing function load?
- Are the restorations under increased load because they are compensating for other missing or weakened tooth units?
An individual who is a heavy grinder or clencher can expect to have more wear and tear than a non-grinder and therefore more replacements over a life time.
In a small percentage of cases there is failure of the implant to integrate. If this is the case, the implant is removed and the area allowed to heal. In due course an implant is placed again possibly in a different site.
- Swelling, bruising
- As with failure to integrate, the implant will be removed and replaced once healing has occurred.
- Poor implant candidates:
- Cases that have poor qauntity and quality of bone
- Presence of Periodontal (gum) disease
If it is determined that bone is deficient in your particular case, bone grafting may be necessary before implants can be placed. In the case of the upper jaw, if CAT Scan reveals that the bone under the sinus cavities is sparse and insufficient for implant placement, it may be necessary to ‘lift’ the sinuses with grafting material. This is called a Sinus Lift Procedure. If implants are required in the front of the mouth in what is called the Aesthetic Zone and there is insufficient gum in the area to allow a pleasing end result, it may be necessary to have gum generated so that when the implant crowns are fitted, they look natural, as if they have emerged from the gum the way a natural tooth would. We sometimes achieve this ‘gum growth’ by using specially adapted orthodontic techniques.
On the day of your appointment, you will be given antibiotics and anti-inflammatory medication prior to the procedure which will take place under local anaesthetic just like any other dental procedure. Most patients do not find implant placement any more demanding than other forms of dental treatment. However, if you feel you would like help with anxiety, we can offer either inhalation sedation, intravenous midazalam conscious sedation or oral sedation. No matter what form of sedation is deemed suitable for you, you will be awake, conscious and responsive at all stages. Swelling can occur after treatment and therefore it is sensible to take anti-inflammatory medication on a regular basis as indicated even in the absence of pain to help with any swelling. Peak swelling can occur 48 to 72 hours after surgical procedures.
Implant supported crown construction
Once the implant has integrated, an impression of the area is taken in order to make a mould to facilitate construction of the implant supported crown in the laboratory. Once made, the crown is fitted, often with a light based cement so that access to the implant root can readily be obtained by the dentist if so desired.
Teeth for extraction that are to be replaced by implants
Every time a tooth is extracted, a certain amount of bone is lost both during the extraction procedure itself and during the healing phase. As the maximum amount of bone is required for implant placement, where possible the tooth is removed by means of a tissue preserving extraction technique. The tooth is extracted in a way which preserves as much bone in the site as possible. Particular instruments are used for this extraction technique. Socket grafting material which is particulate, of bone/equine origin and man made is often placed in the extraction socket to minimise shrinkage in the area and to maintain optimal gum formation. Provisional tooth/teeth are provided on the day of extraction when an implant is to replace the extracted tooth/teeth.
Once the tooth has been extracted, the implant root may be placed on the day of extraction (immediate placement) or the area may be left to heal for a period of time before the implant root is placed (delayed placement). During the time of either implant root integration or tissue healing, it is important that as little pressure as possible is placed on the site that is healing. However, a temporary or provisional tooth needs to be placed for the duration of the integration/healing phase for aesthetic purposes and to maintain the space for an eventual implant restoration.
The type of provisional restoration often used in this situation is a “tooth borne” restoration rather than a “tissue borne” restoration. This is in order to minimise the pressure on the healing area. With a “tooth borne” temporary restoration, the adjacent teeth to the extraction site shoulder the burden of the restoration rather than one that is borne primarily by the gum over the extraction site such as a provisional partial denture.