Access to original canal trajectory after deviation and perforation with guided endodontic assistance

Procedural accidents are eventualities that may occur during endodontic treatment because of lack of attention to detail or even unforeseeable situations. Knowledge of the root canal anatomy and its variations is a prerequisite for successful endodontic treatment. This case report describes an endodontic treatment where there was an intercurrence, generating deviation and perforation, which was solved with the aid of guided endodontics. A 37 years old, ASA1, was referred to the clinic for localisation and treatment of a calcified canal of the second right upper premolar. The tomographic images revealed the presence of only one canal and deviation with apical perforation. With the help of CBCT and CAD/CAM, it was possible to perform the guided access technique even after deviation and root perforation. Once again, this technique proved to be safe and predictable, allowing for a favourable prognosis in the long term.     

Reliability and validity of a new classification of MIH based on severity

To describe a new molar-incisor hypomineralization (MIH) severity scoring system (MIH-SSS) that focuses on the defects’ severity and to assess the sy     

Heteroresistance to Itraconazole Alters the Morphology and Increases the Virulence of Cryptococcus gattii

Cryptococcus gattii is the main etiological agent of cryptococcosis in immunocompetent individuals. The triazole drug itraconazole is one of the antifungals used to treat patients with cryptococcosis. Heteroresistance is an adaptive mechanism to counteract the stress of increasing drug concentrations, and it can enhance the ability of a microorganism to survive under antifungal pressure. In this study, we evaluated the ability of 11 C. gattii strains to develop itraconazole heteroresistance. Heteroresistant clones were analyzed for drug susceptibility, alterations in cell diameter, capsule properties, and virulence in a murine model. Heteroresistance to itraconazole was intrinsic in all of the strains analyzed, reduced both the capsule size and the cell diameter, induced molecular heterogeneity at the chromosomal level, changed the negatively charged cells, reduced ergosterol content, and improved the antioxidant system. A positive correlation between surface/volume ratio of original cells and the level of heteroresistance to itraconazole (LHI) was observed in addition to a negative correlation between capsule size of heteroresistant clones and LHI. Moreover, heteroresistance to itraconazole increased the engulfment of C. gattii by macrophages and augmented fungal proliferation inside these cells, which probably accounted for the reduced survival of the mice infected with the heteroresistant clones and the higher fungal burden in lungs and brain. Our results indicate that heteroresistance to itraconazole is intrinsic and increases the virulence of C. gattii. This phenomenon may represent an additional mechanism that contributes to relapses of cryptococcosis in patients during itraconazole therapy.