Efficacy of chemical sterilization and storage conditions of gutta-percha cones.

AIM: The objective of the present study was to assess the efficacy of 2.5% sodium hypochlorite and 2.2% glutaraldehyde ('Cidex') as sterilizing agents for gutta-percha cones. The efficacy of storage of gutta-percha cones in the presence or absence of paraformaldehyde was also evaluated. METHODOLOGY: Gutta-percha cones artificially contaminated with a suspension of Bacillus stearothermophilus (ATCC/7953) were treated with either 2.2% glutaraldehyde for 10, 15, 30 and 60 min and 10 and 12 h, or 2.5% sodium hypochlorite for 5, 10 and 15 min. The cones were then incubated in thioglycollate medium for the determination of microbial growth. In parallel, additional sterile gutta-percha cones were stored in sealed containers with or without paraformaldehyde tablets for 30 days. The containers were opened 30 min a day and exposed to the environment of a functioning dental clinic. Twelve cones were removed weekly from the containers to determine whether contamination had occurred. RESULTS: The results showed that 2.5% sodium hypochlorite was effective after 5, 10 and 15 min, whereas 10 and 12 h contact with 2.2% glutaraldehyde was necessary to obtain sterilization. There was no contamination of the gutta-percha cones when stored with or without paraformaldehyde. CONCLUSIONS: Sodium hypochlorite (2.5%) and 2.2% glutaraldehyde ('Cidex') proved to be effective as sterilizing agents for gutta-percha cones, with sodium hypochlorite requiring shorter periods of use. No difference was observed between the two methods of cone storage.

[Acute paraplegia. A rare complication of aortic dissection]. / Paraplegia aguda. uma complicação rara da dissecção aórtica.

A 67 year-old normotensive woman had a syncope followed by shock and remained anuric after hemodynamic stabilization. Paraplegia and paresis of the right upper limb, as well as signs of ischemia of the distal lower limbs were noted. The possibility of acute aortic dissection was raised and confirmed by computed tomography. The paraplegia was attributed to an ischemic infarction of the spinal cord. The patient died on the fourth hospital day due to a pericardial temponade. This rare and not well recognized complication of aortic dissection is briefly reviewed.