Immediate implantation is when a dental implant (artificial tooth root) is placed in the alveolus (tooth socket) that has not yet regenerated bone within up to eight weeks after tooth loss. A distinction is made between primary immediate implant placement (immediately after tooth loss) and secondary implant placement, which is performed only after the soft tissues involved have healed. The greatest advantage of primary immediate implant placement, the shortened treatment time due to restoration immediately after tooth loss, is accompanied by a number of disadvantages:
- Lack of accuracy of fit between the bony implant site and the implant.
- Gingiva (gums), which must surround the implant neck, may not be sufficiently available
- Greater tendency to inflammation in the healing phase.
These disadvantages are significantly reduced with delayed, secondary immediate implant placement, usually after four to eight weeks:
- The bony alveolus (tooth compartment) of the tooth to be replaced is completely covered with soft tissue, from which the future gingival margin for the implant can now be aesthetically shaped; for this reason, secondary immediate implant placement in the upper anterior region is in principle preferable to primary implant placement
- The former wound is now safely free of inflammation
For immediate implantation, screw-shaped or cylindrical systems are usually used. Among a number of alloplastic implant materials, titanium currently appears to be the most suitable, characterized by high mechanical stability, radiopacity and sterilizability. Titanium is closely followed by yttrium-reinforced zirconia ceramic. Both materials have in common that the bony implant site does not show any tissue reactions; they are therefore bioinert (i.e. there is no chemical or biological interaction between the implant and the tissue). This allows the implant bodies to heal by being surrounded by bone in direct surface contact without a connective tissue interface (contact osteogenesis). Zirconia has become the material of choice for the so-called abutment located above the gumline due to its tooth color, as it does not shine through ceramic crowns in an unaesthetic manner, unlike metal-colored abutments.
Indications (areas of application)
The indication for immediate implant placement should be narrow and should only be performed under the following conditions:
- Both the bony implant site and the soft tissues involved must be free of inflammation; this means, for example, that immediate implant placement should not be performed after extraction (the removal) of a tooth with apical periodontitis (inflammation of the root tip environment)
- The bone supply must be quantitatively sufficient, i.e. the implant must be surrounded by bone all around and thus be able to be fixed in the bone. Only then, in addition to sufficient primary stability (measurable strength value immediately after implantation) in the medium term, acceptable esthetics of the gingiva (the gums) can be expected.
- Also the bone quality must be such that sufficient strength values can be expected
- Also the further tooth stock and periodontium should be free of inflammation, because otherwise the inflammation-free implant healing is at risk
- Usually atrophies (forms) the alveolar bone (back) after a tooth is accidental or had to be extracted (pulled). The sooner the implantation of an artificial tooth root, the more effectively this alveolar ridge atrophy can be prevented
However, immediate implantation does not necessarily mean that the implant can also be subjected to immediate loading postoperatively. For this, in turn, must also be particularly favorable conditions, since in the healing phase only a limited, cautious load is allowed:
- The occlusion conditions (occlusion conditions) must allow careful loading, e.g., of a single implant with a temporary crown (temporary crown restoration)
- When restoring an edentulous jaw, the implants must be statically placed in such a way that a favorable masticatory load distribution results; only then can the implants, stabilized via bars or bridge-like fixed prostheses be immediately loaded
Contraindications
- Children
- Adolescents who are still in the growth phase
- Wound healing disorders in general diseases, such as diabetes mellitus (diabetes).
- Reduced general condition
- Weakened immune defenses
- Lack of surrounding bone substance
Before surgery
Basically, not every jawbone and not every patient is suitable for implant restoration. Pre-implantological must therefore be performed in-depth diagnostics:
- General anamnesis: to exclude general medical contraindications.
- Mucosal findings
- Bone findings
- X-ray diagnostics
- Assessment of bone quantity and quality
- Selection of the implant size
In addition to diagnostics, it is necessary to provide the patient with comprehensive information about the alternative implantation methods, alternatives to implantation itself, risks and contraindications, as well as further postoperative procedures. Risks include, for example:
- Injury to adjacent areas and nerves
- Material incompatibilities
- Infection of the surgical area
- Delayed wound healing
- Implant loss
- Poor oral hygiene
The surgical procedure
Immediate implantation can be performed in principle under local anesthesia (local anesthesia). Preparation of the surgical site under sterile procedure is essential. Intraoperatively,:
- Incision
- The implant position can only be influenced to a limited extent, as this is largely predetermined by the alveolus (the tooth socket) of the tooth to be replaced
- Preparation of the bony implant site with the help of special instruments precisely matched to the implant size.
- Checking the primary stability (strength of the implant immediately after placement).
- Placement of a closure screw for the healing phase and closure of the wound with sutures or
- Alternatively, in case of immediate loading, supply with abutment and e.g. a crown as a temporary denture.
- X-ray control of the implant position
After the operation
Postoperatively, sutures are removed after one week at the earliest and regular follow-up checks are performed during the healing phase, which lasts three to four months. Thereafter, if the procedure is two-stage, the implant is exposed in another operation. The cover screw located in the implant post is replaced here by a so-called gingiva former, which remains in the implant until the final prosthetic restoration.
Possible complications
Possible complicationsmay arise intraoperatively (during surgery), postoperatively, or even later when the implant is exposed to the usual stresses of mastication:
- Intraoperatively: e.g., disproportionate bleeding, injury to nerves, opening of the maxillary or nasal cavity, injury to adjacent teeth, severe inaccuracies of fit between the implant and the implant site
- In the healing phase: e.g., disproportionate pain, hematoma (bruising), infection (inflammation) of the surgical area, postoperative bleeding
- In the loading phase: e.g. implant fracture (breakage), problems with the prosthetic superstructure, peri-implantitis (inflammation of the bony implant environment) up to the loss of the implant.
