The document discusses various techniques for preparing curved root canals, including circular filing, anti-curvature filing, and avoiding procedural errors that could lead to perforations, ledges, or zipping of the foramen. It addresses initial access of non-vital posterior teeth, enlarging the orifice, and removing interferences. The preparation of the coronal two-thirds is outlined along with achieving direct line access and apical instrumentation. Completing the preparation of curved root canals requires various techniques to shape the canal while avoiding complications.

1. Preparation Of Curved Root
Canal
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7. Circular filing Anti curvature filing
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8. Perforations in access cavity prep
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9. Strip perforation
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10. Procedural error
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11. Procedural error
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12. Procedural error
Dentine mud Ledge Elbow Perforation Strip perforation
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13. Zipping
When a curved foramen is filed
with a small file with pressure
against the outer side of the
curvature, repeated filing Zips and
transport the foramen.
The curved area of the foramen is
not cleaned and retains tissue
debris.
Foramen cannot be obturated
totally and
failure of the RCT is certain.
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14. Non-vital posterior tooth
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15. Initial access Access to the pulp
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16. Withdrawal action Smoothening walls
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17. Orifice enlargement
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18. Remove interferences Uses of gates bur
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19. Preparation of coronal two third
Number 3 Gates bur
Number 2 Gates bur
Number 1 Gates bur
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20. Direct line access Anti--curvature filing
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21. Apical instrumentation Completed preparation
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