Computed tomography evaluation of residual root thickness after pre-flaring using gates Glidden drills: The sequence...

Area of Science:

• Endodontics
• Dental Anatomy
• Radiology

Background:

• Pre-flaring is a crucial step in endodontic treatment.
• Maintaining root structure integrity, especially in mandibular molars, is vital for successful outcomes.
• Gates-Glidden (GG) drills are commonly used for pre-flaring, but their impact on root thickness requires evaluation.

Purpose of the Study:

• To assess the residual root thickness in mesiolingual (ML) canals of mandibular molars after pre-flaring with different Gates-Glidden (GG) drill sequences.
• To compare the effects of step-back versus crown-down preparation techniques on root wall thickness.

Main Methods:

• Computed tomography (CT) scans were used to measure minimum initial root thickness (MIRT) at various levels in 60 mandibular first molars.
• Samples were divided into two groups: step-back (G1) and crown-down (G2) techniques, both using anti-curvature filing.
• Minimum residual root thickness (MRRT) and removed dentin were analyzed using CT imaging and statistical tests (t-test, ANOVA).

Main Results:

• No significant difference in initial root thickness (MIRT) was observed between the two groups.
• The crown-down group (G2) showed a greater minimum residual root thickness (MRRT) across all measured sections, though the difference was not statistically significant.
• Average MRRT remained above 0.5 mm in all groups and sections, indicating substantial root structure preservation.

Conclusions:

• Gates-Glidden (GG) drills, when used appropriately, are safe and effective for pre-flaring mesiolingual canals of mandibular first molars.
• Both step-back and crown-down techniques, with anti-curvature filing, can preserve root thickness in the furcation areas.
• The choice of GG drill sequence may not significantly impact residual root thickness, suggesting flexibility in technique selection when initial root thickness is adequate.