Purpose: To investigate the effect of root canal and post space preparation on the remaining dentine thickness
in the apical region of maxillary central and lateral incisors.
N= 50 extracted maxillary incisors (25 centrals and 25 laterals).
Materials and Methods:
-Teeth were mounted and then sectioned at 5 and 7 mm from the apex.
-Digital image analysis was used to measure dentine thickness for each section at eight sites: labial, mesial, distal,
-palatal, mesio-labial, disto-labial, mesio-palatal and disto-palatal (before and after canal preparation and post space preparation)
-Canal preparation was performed using K3 rotary system.
– Central and lateral incisors were divided into five groups each (n = 5) :G 1 Parapost drill size 4.5, G 2 size 5, G3 size 5.5, G4 size 6 and G5 size 4 gates glidden.
Most highlighted Results:
-For both teeth, and at the two levels there was a significant difference (P < 0.001) between the baseline dentine thickness and that remaining after post-space preparation at all sites. (RDT at the 5mm portion was less than the RDT at 7 mm)
-The average amount of dentine removed ranged from 0.2 to 0.5mm and It was greatest on the labial side of the canal.
-There was a significant difference between drills size 6 and the other groups in the total amount of dentine removed (3.5).
-If a post has to be used, long and large size posts should be avoided for central and lateral incisors. Root size and root canal morphology should be the leading factors in post selection.