RESUMO
This study evaluated the microhardness and histomorphology of bovine enamel when 35% hydrogen peroxide is used. A total of 44 specimens were adapted to removable devices used by 11 individuals subjected to dental caries challenge. A decrease in microhardness was observed for all groups after the cariogenic challenge. Microscopic analysis revealed that fragments subjected to cariogenic challenge associated with bleaching had more intense superficial histologic changes, but the depth of the lesions remained unchanged. It was concluded that 35% hydrogen peroxide enhanced the reduction in hardness and histomorphologic changes in the enamel surface exposed to cariogenic challenge.
Assuntos
Esmalte Dentário/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Clareadores Dentários/farmacologia , Desmineralização do Dente/fisiopatologia , Adulto , Animais , Biofilmes , Cariogênicos/farmacologia , Bovinos , Cárie Dentária/patologia , Cárie Dentária/fisiopatologia , Esmalte Dentário/patologia , Dureza , Humanos , Microscopia Eletrônica de Varredura , Microscopia de Polarização , Sacarose/farmacologia , Desmineralização do Dente/patologia , Adulto JovemRESUMO
Ten possible cases of tropical spastic paraparesis (TSP) in Northeastern Brazil (Ceará) are presented. They show the typical symptoms and signs of TSP consisting of weakness of the lower limbs, spastic gait, hyperreflexia, bladder dysfunction and variable signs of posterior columns impairment. The laboratory examinations excluded other compressive, infective, degenerative or demyelinating lesions of their spinal cord. Our patients age ranged from 21 to 59 years, all were of black origin and all were of lower social class. There was a slight preponderance of females. An etiological implication of a retrovirus (HTLV-I) has been shown for TSP, but for lack of technical conditions we could not determine it in our patients, and that stands as our subsequent step in those and further cases.
