The Shield system classifies a diseased form of these structures caused by a defective sialophosphoprotein (“sialo-phospho-protein”) named after one of its substructures. A hypoplasia of these structures is associated with stunted Retzius stria (10[1])due to (10[1])reduced ameloblast (“uh-MEL-oh-blast”) activity. A part (10[1])of these structures is capped by materials like zinc oxide eugenol and mineral trioxide aggregates. (10[1])Defects in the epithelial (10[1])rests of Malassez can cause masses to form in these structures’ cementum layer. (10[4])These structures (10[2])are damaged (10[1])by (10[2])Streptococcus (10[1])mutans (10[1])biofilms (10[2]-5[2])that secrete (10[2]-5[1])dextran (10[2])and lactic (10[3])acid. (10[3]-5[2])These (10[3])structures (10[1])can (10[1])be repaired (10[1])using nano-hydroxyapatite (10[2]-5[3])therapy. (10[6])Epoxy-bound (10[2])gutta-percha (10[1])is used (-5[1])to fill these structures’ (10[1])pulp (10[1])chambers. (10[4])For 10 points, (10[1]-5[1])name these structures (10[1])that are disinfected in root (10[1])canal treatments. (10[3])■END■ (10[14]0[2])