Effect of Calcium Hydroxide as a Root Canal Dressing Material on Dentin Fracture Strength In Primary Teeth-In Vitro Study

Objectives: The aim of the present study was to assess the effect of calcium hydroxide as a root canal dressing material on dentin microtensile fracture strength in human primary teeth in vitro. Study design: Thirty primary anterior teeth with root canals packed with calcium hydroxide were divided into groups of ten and immersed in saline at room temperature for 7, 30 and 90 days. Ten teeth with root canals filled with sterile saline were the control group. Microtensile fracture strength was measured in Mechanical tester Lloyd testing machine. Results: There was a significant difference (P < 0.05) between the fracture strength of the calcium hydroxide-filled teeth after 90 days (19.1 MPa) compared with the control (35.8 MPa). Dentin microtensile fracture strength of the calcium hydroxide-filled teeth decreased at an average of 0.142 MPa per day. Conclusion: Calcium hydroxide placed in root canals for an extended time had a significantly negative effect on root strength. Long-term success of root canal treatment in primary anterior teeth is estimated as 65% with most of the failures result from trauma recurrence.