in endodontics, treatment of an open apex tooth with necrotic pulp is a problem. it seems that with promotion of remnants of hertwig’s epithelial sheath or rest of malassez accompany with a good irrigation of root canal we can expect root formation.

We analyzed the structure of foliicolous lichen communities in northernmost lowland forest Neotropics, Los Tuxtlas Tropical Biology Station Veracruz, Mexico, and its dependence on phorophyte microclimate. Along a 420-m long transect with 15 equidistant sampling points, within 10 m radius each point, we sampled total 137 phorophytes 411 leaves. The represented 13 species, diverse leaf traits reg...