Unlike metals for which allergic intolerance reactions can be attributed exclusively to lymphocyte-mediated type IV sensitisations, immune responses to composite materials containing acrylates as well as other non-metallic materials may also be IgE-mediated responses (type I allergic reactions).
Immediate-type allergies should be considered if the symptoms develop a few hours (in rare cases even minutes) after inserting non-metallic dental restoration materials. Local but also systemic oedematous, wheal-like mucous membrane disorders are common with these rarely having a typical local morphology because of the special features of mucous membranes.
In the literature, there are indications that patients with known immediate-type allergies (hay fever, insect toxin and dust mite allergies) are also more often affected by an acrylate allergy, which in principle suggests a principle predisposition to type I allergies.
For many classical type I allergens (e.g. tree pollen), the specific IgE can be determined in automated EAST or RAST procedures in almost every laboratory. Acrylates or, for example, the components of root canal filling materials are not yet commercially available. The diagnostics can therefore only be done using cellular test systems.
The basophil degranulation test (BDT) is a modern in vitro method to detect type I allergic sensitisation as well as pseudo-allergies. The test is also known as the leukotriene release test, basophil activation test or CAST test. The advantage of this test is that both standard allergens (e.g. acrylate monomers) and native material samples can be tested in the laboratory after preparation. This allows testing of material samples of unknown composition, for example (including from prosthesis material or plastic chips and shavings obtained in situ).
The results of the allergen-stimulated test batches are compared to positive and negative controls. A value greater than 200 pg/mL means that there is a type I sensitisation present. A negative result rules out an immediate-type sensitisation with a high degree of certainty.
Regarding sensitivity and specificity, the BDT has proven to be clearly superior in our laboratory compared to other in vitro provocation tests such as the histamine release test or the CD63 test.
The standard acrylate profile includes:
All other common acrylates are available in the laboratory for testing.
It is also possible to send a material sample (plastic test plates, samples of root canal filling materials, native harvested shavings, cement samples and so on) to the laboratory which can then be directly tested in the BDT. The materials must be sent in together with the blood. A range of materials are also kept in stock in the laboratory and have been established for testing (see the reverse of the dentistry request form). Particularly for preventive testing, the materials should be in the same state as that in which they will later be used in the patient (e.g. cured composite cement, polymerised plastic).
2 mL EDTA blood or heparin blood for each allergen or native material. The heparin Monovettes in the LTT collection set can be used. We are also happy to send you individual collection tubes. The laboratory must receive the samples within 24 hours of collection. The blood should be stored and transported at room temperature.
Hypersensitivity to local anaesthetics may be based on an allergy.
Particularly when symptoms develop within minutes to a few hours, an IgE-mediated sensitisation or pseudo-allergy must be considered a possible cause. Anaphylaxis, that is, systemic hypersensitivity reactions which in some cases may be life threatening have been described. For a suspected intolerance to local anaesthetic, the preparations should be tested using the BDT.
All preparations can be used in the BDT in principle if an ampoule or tablet is sent to the laboratory. The following active ingredients in local anaesthetics are kept in the laboratory and therefore do not have to be sent in: mepivacaine, articaine, lidocaine, prolocaine and ubistesin. For positive results, we prepare an allergy passport. A preparation that has tested positively should not be used as a matter of course.
2 mL EDTA blood or heparin blood for each preparation. The heparin Monovettes in the LTT collection set can be used. We are also happy to send you individual collection tubes. The laboratory must receive the samples within 24 hours of collection. The blood should be stored and transported at room temperature.