In vitro Validation of Quantitative Light-Induced Fluorescence for the Diagnosis of Enamel Fluorosis in Permanent Teeth.

This study aimed to validate quantitative light-induced fluorescence (QLF) as a diagnostic tool for mild and moderate enamel fluorosis in permanent teeth, comparing it to visual diagnosis and histological assessment completed using polarized light microscopy (PLM). The buccal surfaces of 139 teeth were visually classified using the Thylstrup and Fejerskov Index (TFI) into sound (TFI 0; n = 17), mild (TFI 1-2; n = 69), and moderate (TFI 3-4; n = 43) fluorosis. Fluorosis was then assessed with QLF (variables ΔF, A, and ΔQ at 5-, 15-, and 30-radiance thresholds) using as reference areas the entire surface and a region of interest (ROI), identified as the most representative region of a fluorosis lesion. PLM images of longitudinal thin sections including the ROI were assessed for histological changes. Correlations among TFI, PLM, and QLF were determined. A receiver-operating characteristic curve was conducted to determine QLF's diagnostic accuracy when compared to the TFI and PLM assessments. This was used to assess the probability that the images were correctly ranked according to severity as determined by PLM and TFI. A positive correlation was found between QLF and PLM, and between QLF and TFI. QLF showed the highest sensitivity and specificity for the diagnosis of mild fluorosis. There was also a strong agreement between TFI and PLM. The selection of a ROI resulted in a stronger correlation with TFI and PLM than when the entire surface was used. The study results indicate that defining an ROI for QLF assessments is a valid method for the diagnosis of mild and moderate enamel fluorosis.

Protective effect of the dental pellicle against erosive challenges in situ.

The acquired dental pellicle helps prevent erosion, but the protection level is unknown. This in situ study tested whether a two-hour pellicle protects against different erosive challenges by orange juice. Subjects wore palatal appliances loaded with either enamel or dentin specimens. Pellicle was allowed to form, or not (control), on the surfaces of the specimens intra-orally for 2 hrs before the erosive challenges of 0 (control), 10, 20, and 30 minutes' duration. Specimens were randomly removed from the appliances after each challenge. Percentage of surface microhardness change (%SMC) was determined for the enamel specimens, and that of mineral loss and lesion depth for the dentin specimens. Enamel specimens with the pellicle showed a significantly lower %SMC, only after the 10-minute challenge. No protection was found for dentin. It was concluded that the acquired pellicle reduced dental erosion, but that this effect was limited to the less severe erosive challenge on enamel surfaces.

Influence of the organic matrix on root dentine erosion by citric acid.

This investigation was conducted in an attempt to clarify the role of the organic matrix in bovine dentine demineralisation by 1% citric acid. Dentine slabs (n = 15) were treated for 2 min with 10% sodium hypochlorite (NaOCl, a strong protein solvent), 2% glutaraldehyde (GDA, a protein fixative) or deionised water (DIW, as negative control) prior to each of 5 demineralisation periods of 30 min. The mineral loss (DeltaZ), lesion depth (LD) and surface loss (SL) were determined after each period of demineralisation, by transverse microradiography. The NaOCl-treated group showed higher DeltaZ and LD than the GDA- and DIW-treated groups. No differences between GDA and DIW groups were found. The DeltaZ and LD profiles were explained by quadratic fits (r(2) >0.80; p = 0.001) in all groups. SL was detected only in the NaOCl-treated group. The data suggested that the maintenance of the organic matrix in the lesion might be important to reduce the erosion progression rate.

[The ACHEI Program: Chagas' disease awareness through comprehensive education in the municipality of Maringá, Northwest Paraná, Brazil]. / Programa ACHEI: Atenção ao chagásico com educaçao integral no município de Maringá e região noroeste do Paraná, Brasil.

This study analyzes 131 chagasic patients from different endemic areas that came to the Chagas' disease laboratory at the Maringa State University. The subjects discovered they were infected principally because they presented symptoms (58%) or donated blood (29.4%). During etiologic treatment for Trypanosoma cruzi, 45.2% of benznidazole users complained of side effects. Based on these data, the ACHEI program (Chagas' Disease Awareness through Comprehensive Education) was developed, which is a multiprofessional/interdisciplinary extension project. Monthly meetings are held that are divided into two parts: The first half of the meetings provide specific information, including the distribution of brochures explaining Chagas' disease transmission, symptoms and treatment. The second half of the meetings focuses on psycho-social assistance and includes topics such as self-esteem and personal responsibility. The meetings provide an environment for chagasic patients to share their concerns regarding post-diagnosis quality of life, fear, anxiety, stigma and family and social group relationships. In short, the meetings offer an opportunity for patients to reflect on their situation and to discover ways to deal with their disease.

Clinical utility of a 22-kDa growth hormone-specific assay.

Human growth hormone (hGH) circulates in different molecular forms, with the 22-kDa monomer being the predominant one and the 20-kDa variant corresponding to 5 to 15% of the serum hGH on a weight basis. Using monoclonal antibodies with different specificities we developed two immunoenzymometric assays, one with 22 + 20-kDa specificity and the other specific only for the 22-kDa form. Both assays used microtiter plates as solid phase and streptavidin-peroxidase for color development; intra-assay CV was less than 10% in the range of 1 to 100 mIU/l for the 22 + 20-kDa assay and in the range of 3 to 100 for the 22-kDa assay, with an inter-assay CV of less than 14% for both assays; sensitivity was 0.2 mIU/l for the 22 + 20-kDa assay and 0.5 mIU/l for the 22-kDa assay. The two assays were compared by measuring 200 serum samples with detectable hGH levels by both assays. Higher values were obtained with the 22 + 20-kDa assay (62.1 +/- 5.9 vs 59.2 +/- 6.1 mIU/l, mean +/- SD) with a correlation coefficient (r) of 0.99. In no clinical condition (28 patients with growth retardation and 14 acromegalics) did the two assays give discrepant values. We conclude that there was no practical advantage in using an assay with specificity restricted to the 22-kDa form for measuring hGH in clinical serum samples.

Clinical utility of a 22-kDa growth hormone-specific assay

Human growth hormone (hGH) circulates in different molecular forms, with the 22-kDa monomer being the predominant one and the 20-k-Da variant corresponding to 5 to 15% of the serum hGH on a weight basis. Using monoclonal antibodies with different specificities we developed two immunoenzymometric assays, one with 22 + 20 k-Da specificity and the other specific only for the 22-kDa form. Both assays used microtiter plates as solid phase and streptavidin-peroxidase for color development; intra-assay CV was less than 10% in the range of 1 to 100 mlU/l for the 22 + 20 kDa assay and in the range of 3 to 100 for the 22-kDa assay, with an inter-assay CV of less than 14% for both assays, sensitivity was 0.2 mlU/l for the 22 + 20 kDa assay and 0.5 mlU/l for the 22-kDa assay. The two assays were compared by measuring 200 serum samples with detectable hGH levels by both assays. Higher values were obtained with the 22 + 20 kDa assay (62.1 ñ 59.2 ñ 6.1 mlU/l, mean ñ SD) with a correlation coefficient (r) of 0.99. In no clinical condition (28 patients with growth retardation and 14 acromegalics) did the two assays give discrepant values. We conclude that there was no practical advantage in using an assay with specificity restricted to the 22-kDa form for measuring hGH in clinical serum samples