Microcracks after apicoectomy with three surgical instruments: A comparative scanning electron microscopy study

Dentinal microcracks during apicoectomy may be influenced by the instrument used for root-end resection and preparation. Recognizing instrument-related crack formation is important for safer microsurgical choices.

To evaluate dentinal microcracks on root-end surfaces after resection with a tungsten carbide bur (TCB), a diamond-coated ultrasonic tip (DUT), and a surgical saw (SS), using scanning electron microscopy (SEM).

Sixty extracted single-rooted human canines were endodontically prepared and randomly allocated into three groups (n = 20) according to the instrument used. Resections were performed perpendicular to the long axis, removing 3 mm of the apex. Root-end surfaces were examined under SEM (×25) and microcracks classified into five subtypes.

Data were analyzed with SPSS 20.0 (SPSS Inc., Chicago, USA) using descriptive statistics and Chi-square tests. Odds ratios and logistic regression were applied to identify factors associated with the intervention. A significance level of α =0.05 and 95% confidence intervals were adopted.

Instrument type influenced crack formation. The SS produced the highest proportion of complete cracks, whereas the DUT produced the lowest. Differences between groups were statistically supported.

The DUT may minimize dentinal microcracks compared with the SS. Appropriate instrument selection and standardized technique can help reduce structural damage during apicoectomy.