To quantitatively assess canal preparation by single file F2 ProTaper instrument in reciprocation. N = 25 Mn first molar M canals with separate apical foramina & curvatures 20-40°
- Teeth pre-scanned with micro-CT à access made & WL (.08)determined with xray à canals randomly assigned to 2 groups à Tx provided à final micro-CT taken
- Group 1 = conventional ProTaper sequence: glide path made with 10 or 15 k file to WL à coronal prep with SX only à rotary instrumentation with S1, S2, F1, F2 to WL at 250rpm
- Group 2 = Single file group (Yard): ProTaper F2 (25.08) in reciprocating movement using light apical pressure until WL is reached. Rotation: CW 4/10, CCW 2/10. Speed: 400rpm.
- Evaluation criteria: (1) increase in canal volume (ie, amount of removed dentin) up to level of CEJ & apical 4mm only, (2) canal transportation, (3) mean transportation, (4) duration of root canal preparation
- For both groups, no preparation errors, instrument fractures. Single file technique faster (38 vs 56 sec)
- No s.s. difference between the two groups except coronal transportation toward the furca of group2
Pre-flare the coronal third if considering reciprocation.