A superstructure is a dental prosthesis attached to an implant. This can be a crown, a bridge or even a denture. The implant itself is surgically placed (implanted) in edentulous areas of the jaw and assumes the function of an artificial tooth root, which serves to attach the superstructure. An implant that heals without complications is in no way inferior to the strength of a natural healthy tooth. Titanium is used for the production of implants because it does not cause any undesirable side effects such as allergies. Due to its high stability, titanium can withstand the pressure loads that occur during chewing. Implants can offer quite a few advantages, such as:
- They help dentures that fit poorly due to unfavorable jaw conditions, to a firm hold.
- They can preserve healthy teeth from crowning.
- Offer the superstructures aesthetically good results.
- Jawbones in edentulous areas recede and thus lose stability. This is not the case in the area of implants.
Indications (areas of application)
Implants together with their superstructures find application:
- For single tooth replacement – e.g. to preserve caries-free neighboring teeth from crowning for a bridge.
- For the extension of shortened tooth rows
- In the reduced residual dentition – e.g. to avoid removable dentures.
- In the edentulous jaw – e.g. to give a prosthesis better hold.
- In poor anatomical conditions for the retention of conventional dentures – e.g. condition after tumor resection.
- For abutment augmentation – to avoid removable dentures.
Contraindications
General contraindications
- Increased bleeding tendency
- Hemorrhagic diathesis (pathologically increased bleeding tendency).
- Severe cardiovascular disease
- Heart valve replacement
- Condition after bacterial endocarditis (endocarditis of the heart).
- Bypass
- Severe bone metabolism disorders – e.g. osteogenesis imperfecta (brittle bone disease).
- Osteoporosis therapy with bisphosphonates.
- Liver cirrhosis (liver shrinkage – end stage of chronic liver disease).
- Rheumatic diseases/collagenoses – e.g. rheumatoid arthritis, scleroderma (sclero = hard, dermie = skin) – rare autoimmune disease associated with hardening of connective tissue of the skin alone or of the skin and internal organs (especially digestive tract, lungs, heart and kidneys), Sjögren’s syndrome – autoimmune disease from the group of collagenoses in which immune cells attack salivary glands and lacrimal glands. Sjögren’s syndrome manifests itself in morphological changes in the salivary and lacrimal glands, causing chronic parotitis (inflammation of the parotid glands), keratoconjunctivitis sicca (dry eye syndrome; sicca syndrome; cessation of secretion from lacrimal glands), xerostomia (dry mouth) and rhinitis sicca (dry nasal mucosa)
- Condition after organ transplantation
- Decreased immunological defenses of the patient – e.g. HIV, immunosuppressants, cytostatic drugs.
- Steroid therapy/glucocorticoid administration (cortisol, prednisone, prednisolone, betamethasone, dexamethasone, etc.).
Temporary (transient) contraindications.
- Incomplete jaw growth – implantations between the ages of 18 and 20 at the earliest, after growth completion.
- Untreated periodontal disease (inflammatory diseases of the periodontium).
- Gravidity (pregnancy)
- Acute inflammation
- Drug abuse (drug abuse)
- Heavy smoking
- Condition before/after radiotherapy (radiotherapy) – increased risk of infection, implantations after one year at the earliest after careful consideration of the alternatives.
- Not adjusted diabetes mellitus
- Mental illness
Local contraindications
- Untreated periodontal disease
- Unfavorable bone situation – weigh bone augmentation if necessary.
- Osteomyelitis (bone marrow inflammation)
- Dysgnathia (jaw malocclusions)
- Dysfunctions
- Pathological oral mucosal changes – e.g.B. Leukoplakia (hyperkeratosis of the mucous membranes or lip skin, which can be potentially dysplastic).
- Residual dentition in need of treatment
- Insufficient oral hygiene
- Xerostomia (dry mouth)
- Macroglossia (enlarged tongue)
The procedure
Immediately after the implant is placed, it is usually covered by mucosa. After the healing phase, which usually takes three to six months, the mucosa over the implant is opened again slightly to expose the implant. Now, initially for another two weeks, a so-called healing spacer is inserted to prevent the mucosa over the implant from closing again. An impression is taken with the aid of impression posts. This is used by the dental laboratory to produce the final dental prosthesis, the superstructure. The implant has a thread inside it, the so-called internal thread. A small screw is incorporated into the superstructure – for example, a crown – which is a perfect fit for the internal thread of the implant. About two weeks after uncovering the implant, the healing space is removed and the new superstructure is screwed to the implant for an exact fit. Alternatively, crowns and bridges can be conventionally fixed (cemented).
After the procedure
Regular, above-average oral hygiene and follow-up visits are essential for the long-term success of implants.