Effect of organic acids in dental biofilm on microhardness of a silorane-based composite

OBJECTIVES: This study evaluated the effect of lactic acid and acetic acid on the microhardness of a silorane-based composite compared to two methacrylate-based composite resins. MATERIALS AND METHODS: Thirty disc-shaped specimens each were fabricated of Filtek P90, Filtek Z250 and Filtek Z350XT. After measuring of Vickers microhardness, they were randomly divided into 3 subgroups (n = 10) and immersed in lactic acid, acetic acid or distilled water. Microhardness was measured after 48 hr and 7 day of immersion. Data were analyzed using repeated measures ANOVA (p < 0.05). The surfaces of two additional specimens were evaluated using a scanning electron microscope (SEM) before and after immersion. RESULTS: All groups showed a reduction in microhardness after 7 day of immersion (p < 0.001). At baseline and 7 day, the microhardness of Z250 was the greatest, followed by Z350 and P90 (p < 0.001). At 48 hr, the microhardness values of Z250 and Z350 were greater than P90 (p < 0.001 for both), but those of Z250 and Z350 were not significantly different (p = 0.095). Also, the effect of storage media on microhardness was not significant at baseline, but significant at 48 hr and after 7 day (p = 0.001 and p < 0.001, respectively). Lactic acid had the greatest effect. CONCLUSIONS: The microhardness of composites decreased after 7 day of immersion. The microhardness of P90 was lower than that of other composites. Lactic acid caused a greater reduction in microhardness compared to other solutions.

Psychotic symptoms during hepatitis a infection: a rare case report from Iran

Psychosis, a relatively common condition that affects 3%-5% percent of the population, occurs in a variety of diagnostic contexts. Various medical conditions may lead to the development of psychotic symptoms. To date psychotic disorders due to infection with hepatitis A virus [HAV] have been rarely reported. In this paper, we described an acute psychotic disorder in an 18-year-old male diagnosed with hepatitis A infection . He presented with complaints nausea, vomiting, fever, constipation and abdominal pain of a one week duration. The patient denied a history of substance abuse. Neurological evaluation was normal. Brain CT scan was remarkable for suspicious hyperdense lesions in the basal ganglia, however the EEG was normal. He had visual hallucinations, persecutor/ delusion, disorganized behavior, personality changes, sleep disturbances, and disorganized speech. A psychiatrist diagnosed the patient with psychotic disorder due to HAV and treated him with antipsychotic medications. Following the decline in liver enzyme levels and after several days, the patient became clinically well with regression of his psychiatric signs and schizophrenia-like symptoms. We believe this may be the first reported case of an acute psychotic disorder during active HAV infection. Based on the data we have collected from several references we conclude that the most probable reason for this accompaniment is a type of comorbidity between acute psychotic disorder and HAV infection