The orthodontia makes great success. Many people wear dentures. Plastic and metal products can cause a mechanical irritation, toxic and allergic reactions.
For people with problems in oral cavity the probability of allergic reactions is higher. Many processes can strengthen dissolution and oxidation of dental products. An important factor is electrochemical reactions when in the mouth at the same time there are various metals forming a galvanic cell (like battery). It is necessary to choose materials neutral electrochemically to each other.
Dentures have to adjoin tightly to gingivae. Rubbing of gingivae enlarges probability of penetration allergens in blood both from dentures and food components.
In metal prostheses many metals are used. Nickel, corrosive under the influence of saliva can cause allergic reactions. If the patient had dermatitis from wearing of watch or jewelry use of nickel is contra-indicated.
Chrome, manganese, cobalt are also dangerous. The allergy can develop when using metals of platinum group, for example, palladium. Silver on the contrary, decreases inflammatory reactions and is recommended to use.
Acrylic plastic is capable to cause toxic and allergic stomatitis. Residual monomer which is contained in plastic in quantity of 0.2% is considered the main allergen. If the regimen of production is broken it can amount to 8%.
Also the allergy can be caused by coloring agents applied in esthetic dentistry. Ceramics does not cause allergic reactions.