RESUMO
OBJECTIVES: The purpose of the study was to evaluate the effect of different types of fluoride on tensile properties and surface roughness of titanium based archwires clinically. MATERIALS AND METHODS: Three groups of archwires, namely nickel-titanium (NiTi), heat activated NiTi, and TMA was evaluated clinically. Each group comprised four subgroups, namely as received group, nonfluoride control group, APF gel group (received one application of 1.23% APF gel), and sodium fluoride mouthwash group (patients rinsed twice daily with 0.2% sodium fluoride mouthwash). All the archwires were removed after 3 weeks of clinical use and evaluated for surface roughness with three dimensional optical profiler. Tensile strength and elongation rate was determined with Instron universal testing machine. RESULTS: NiTi, heat activated NiTi, and TMA archwires with APF gel application showed the highest reduction in tensile strength and elongation rate and highest value for surface roughness, followed by sodium fluoride mouthwash group and finally wires without fluoride application. NiTi wires had the highest reduction in tensile strength with APF gel followed by heat activated NiTi and TMA. CONCLUSION: APF gel with highest concentration of fluoride caused most degradation in the tensile properties and surface roughness of titanium based arch wires.
RESUMO
BACKGROUND: Lichen planus (LP) is a chronic, inflammatory disease that affects the skin, mucous membrane, scalp and nails that frequently involves the oral mucosa. Oxidative stress reflects an imbalance between the production of reactive oxygen species and the biological system's ability to readily detoxify the reactive intermediates or repair the resulting damage. It has been suggested that oxidative stress may play a role in the pathogenesis of LP. AIM AND OBJECTIVES: To evaluate the role of oxidative parameters in the pathogenesis of oral LP, estimate the levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GPx) and uric acid (UA) in saliva of oral LP patients and to compare the levels of SOD, MDA, GP and UA in oral LP patients with healthy controls. METHODOLOGY: In this cross-sectional study, 1.5 ml of fasting saliva sample was collected using passive drool method from the study group (30 patients diagnosed as having oral LP) and the control group (30 age-matched healthy volunteers). The unstimulated saliva was collected were analyzed by spectrophotometry. Statistical analysis was done to evaluate and compare the values between groups. RESULTS: The mean values of SOD and MDA in saliva in the study group showed a significant increase in amount when compared with the control group whereas GPx showed a significant decrease in the study group. UA value showed an insignificant difference in the same comparison. INTERPRETATION AND CONCLUSION: Oxidative stress markers as MDA and SOD are elevated, and GPx is decreased in the saliva of oral LP patients.
RESUMO
Epidermoid and dermoid cysts are hamartomas localized on the neck, head, or trunk, usually visible at birth. In some instances, careful medical examination may help to find most epidermoid and dermoid cysts. Ambiguity about their exact pathogenesis exists and dysontogenetic, traumatic, and thyroglossal anomaly theories have been postulated. Histopathologically epidermoid cysts have a cystic capsule lined with thin stratified epithelium. Surgical excision though completes the treatment, complications have been reported. We report three cases of epidermoid cyst on the maxillofacial region.
Los quistes epidermoides y dermoides son hamartomas localizados en el cuello, la cabeza o el tronco, por lo general visibles al nacer. En algunos casos, el examen médico cuidadoso puede ayudar a encontrar quistes epidermoides y dermoides. Existe cierta ambigüedad acerca de su patogenia exacta, postulando teorías disontogenéticas, traumáticas y anomalías del conducto tirogloso. Los quistes epidermoides histopatológicamente tienen una cápsula quística revestida con epitelio estratificado delgado. Aunque la escisión quirúrgica completa es su tratamiento, se han reportado complicaciones. Presentamos tres casos de quiste epidermoides en la región maxilofacial.
