Evaluation of dental material series from patients with dental prostheses and suspicion of delayed hypersensitivity

Abstract: BACKGROUND: Patients with oral sensitivity are common in our practice. Allergic contact dermatitis is one of the most frequent etiologies. OBJECTIVES: Evaluate oral contact dermatitis using the Brazilian standard series and complementary dental series in patients using dental prostheses, with or without oral complaints. Determine specific dental Brazilian series. METHODS: Patients using dental prostheses with or without oral complaints realized patch tests. Brazilian standard series and complementary dental series were used according to ICDRG recommendations. The results were analysed according to age, sex, race, atopic conditions and symptoms associated. RESULTS: From 54 patients tested, 34 (63%) were positive at least to one substance. Nineteen had oral complaints, such as burning mouth, itch or oral erythema. There was no association between atopic condition and tests results. Without the oral series, just 23(42,6%) patients had a positive result. Using the Brazilian standard series with the complementary dental series we improved the positivity of the patch test to 47%. CONCLUSION: In patients using prostheses and with oral complaints, patch tests with Brazilian standard series with complementary dental series improve the tests positivity.

Patch test results in children and adolescents. Study from the Santa Casa de Belo Horizonte Dermatology Clinic, Brazil, from 2003 to 2010

AbstractBACKGROUND:Patch testing is an efficient method to identify the allergen responsible for allergic contact dermatitis.OBJECTIVE:To evaluate the results of patch tests in children and adolescents comparing these two age groups' results.METHODS:Cross-sectional study to assess patch test results of 125 children and adolescents aged 1-19 years, with suspected allergic contact dermatitis, in a dermatology clinic in Brazil. Two Brazilian standardized series were used.RESULTS:Seventy four (59.2%) patients had "at least one positive reaction" to the patch test. Among these positive tests, 77.0% were deemed relevant. The most frequent allergens were nickel (36.8%), thimerosal (18.4%), tosylamide formaldehyde resin (6.8%), neomycin (6.4%), cobalt (4.0%) and fragrance mix I (4.0%). The most frequent positive tests came from adolescents (p=0.0014) and females (p=0.0002). There was no relevant statistical difference concerning contact sensitizations among patients with or without atopic history. However, there were significant differences regarding sensitization to nickel (p=0.029) and thimerosal (p=0.042) between the two age groups under study, while adolescents were the most affected.CONCLUSION:Nickel and fragrances were the only positive (and relevant) allergens in children. Nickel and tosylamide formaldehyde resin were the most frequent and relevant allergens among adolescents.

A new occlusive patch test system comparable to IQ and Finn chambers.

Background: A good patch test system should have good adhesion and contact, and minimal leakage; Finn and IQ patch test system have these properties but are expensive. Aims: To develop a new cost‑effective occlusive patch test system that had good contact with the skin and was non‑irritant. Methods: The system (designated Chamber X) was fabricated using a semi‑permeable tape and a flexible virgin plastic chamber. Chamber X was developed by (i) selecting adhesive tape based on its non irritancy and adhesive potential (ii) testing plastic chamber material for its skin irritancy (iii) testing the assembled system against Finn, IQ and locally available chambers for irritancy, contact, leakage and occlusivity. Results: Chamber X showed better occlusion than IQ, Finn and locally available chambers and was comparable to, (P > 0.05) IQ and Finn in terms of irritancy, contact and leakage. Conclusions: The results demonstrate that the Chamber X offers a cost effective patch test system comparable to IQ and Finn chambers in terms of safety, adhesion, leakage and occlusivity.

Patch tests / Testes de contato

Patch tests were introduced as a diagnostic tool in the late nineteenth century. Since then, they have improved considerably becoming what they are today. Patch tests are used in the diagnostic investigation of contact dermatitis worldwide. Batteries or series previously studied and standardized should be used in patch testing. The methodology is simple, but it requires adequate training for the results to be correctly interpreted and used. Despite having been used for over a century, it needs improvement like all other diagnostic techniques in the medical field.

Os testes de contato foram introduzidos, como ferramenta diagnóstica, no final do século XIX. Desde então passaram por diversos aprimoramentos tornando-os o que são hoje. Eles são utilizados na investigação diagnóstica das dermatites de contato em diferentes partes do mundo. Devem ser aplicados com a utilização de baterias ou séries previamente estudadas e padronizadas. A metodologia é simples, mas requer treinamento adequado para sua interpretação e bom aproveitamento dos resultados obtidos. Apesar de ser utilizado há mais de um século, necessita de aprimoramentos como todas as outras técnicas utilizadas para investigação diagnóstica na área médica.