The experimental study of the influence of root canal enlargement on the susceptibility of dental roots to vertical fracture

Purpose: to study the influence of the extent of root canal enlargement on the resistance of tooth to vertical root fracture. Bovine teeth were used (n = 20) from which experimental cylindrical samples were fabricated and divided into two groups according to root canal diameter. The sampled were subjected to vertical static load in universal testing machine until vertical root fracture occurrence. Average values of maximal load were fixed in each group. Mann-Witney test was used in SPSS Statistics program to assess the significance of differences between groups. Average load values for the group with smaller were 438,60 ± 29,84 kgf (median was 437,88 kgf) and in the group with larger canal diameter were 293,21 ± 68,23 kgf (median was 301,79 kgf). The differences between groups were statistically significant (p = 0,001). It was shown that the extent of root canal influences on the resistance of the root to fracture