T‐lymphocyte and Langerhans cell distribution in normal and allergically induced oral mucosa in contact with nickel‐containing dental alloys

Abstract

An in vivo comparison was made between the contact allergic stomatitis‐inducing capacity of nickel, nickel‐containing dental alloys and a non‐corrosive precious metal. Fifteen patients with a positive allergic skin reaction to nickel were divided into 3 groups (A, B and C). The patients in Group A (n=4) were fitted with an intra‐oral corrosion‐resistant nickel‐chromium Alloy A; the patients of Group B (n=5) received a more corrosion prone nickel‐chromium Alloy B and in Group C (n=6) strongly corroding pure nickel was used. A corrosion‐resistant foil of pure palladium was placed on the contralateral side. Reactivity of pure nickel foil was also tested on the skin in Group C. Immunohistological examination of the oral mucosa on the test and reference sides was performed with monoclonal antibodies directed against T‐lymphocyte subsets and Langerhans cells (LC). The results showed that at the pure nickel site the LC did increase significantly in the connective tissue (approx. 4×) of the oral mucosa. However, statistical analysis of all 6 patients of Group C together showed no corresponding increase of LC in the epithelium at the site with the pure nickel, although a numerical increase of LC was noted in the epithelium adjacent to the pure nickel foil in 2 patients, which was remarkable. It can be concluded from statistical analysis that both the reference foils and the test foils can influence the number of suppressor/cytotoxic T‐lymphocytes in the connective tissue. The results showed also that pure nickel can cause a strong infiltration of helper/inducer T‐lymphocytes, especially in the connective tissue. This infiltration of T‐lymphocytes and LC was not observed on the reference sides or on the test sides with the nickel‐containing foils in Groups A and B. It could be concluded that neither clinically nor immunohistologically is the presence of high percentages of nickel in the nickel‐containing dental alloys necessarily associated with allergic contact stomatitis in nickel‐allergic patients.

Langerhans Cells of Human Mucosa

“…In the lympho-epidermic system of the pathological oral mucosa, the LC are involved in two steps; 1) an increase in the number of LC before the migration of lymphocytes during the inflammatory process (40), the presence of CDI + LC during the inflammation of odontogenic cysts (41), or after allergically induced oral mucosa in contact with nickel-containing dental alloys (42), and the increase of the LC HLA-DR Ag expression concomitant with the appearance of this Ag on the subepithelial T lymphocytes in lichen planus patients (43).…”

Knowledge, Attitude And Practice Regarding Nickel Hypersensitivity In Patients Undergoing Orthodontic Therapy Among Interns. - A Questionnaire Survey.

“…(Lowey, 1993) It is estimated that 11% of all women and 20% of women between the ages of 16 and 35 years have a sensitivity to nickel.6-8 Nickel-induced contact dermatitis is a Type IV delayed hypersensitivity immune response occurring at least 24 hours after exposure. (Al-Tawil, Marcusson and Moller, 1985) (Loon et al, 1988) It has been shown that the level of nickel in saliva and serum increases significantly after the insertion of fixed orthodontic appliances. (Souza, de Souza and de Menezes, 2008) Nickel leaching from orthodontic bands, brackets, stainless steel or Ni-Ti archwires has been shown in vitro to occur within the first week and then decline thereafter.…”