Endodontics: Step-Back Technique

Step-Back Technique in Endodontics

• Emphasizes keeping the apical preparation small, in its original position, and producing a gradual taper coronally
• Involves preparation of the apical third initially, followed by the middle and coronal third of the canal using larger instruments

Phases of Step-Back Technique

• Phase I: Apical Preparation
  • Evaluate the carious tooth before initiating endodontic treatment
  • Prepare the access cavity, locate the canal orifices, and establish the working length
  • Use a pathfinder to establish the working length
  • Insert the first instrument into the canal with a watch winding motion, remove, and irrigate
  • Lubricate the instrument to emulsify fibrous pulp tissue
  • Recapitulate the canal with previous smaller number instruments to break up apical debris
  • Repeat until a size 25 K-File reaches the working length
• Phase II: Preparation of Remainder of the Root Canal
  • Gradually step back while increasing in size
  • Insert the instrument into the canal with a watch winding motion, remove, irrigate, and recapitulate
  • Use Gates Glidden to prepare the coronal root area
  • Refine the root canal with a master apical file using push-pull strokes to achieve a smooth taper form

Procedures in Step-Back Technique

• Set rubber stops on files #15, 20, 25, 30, and 35 at the working length
• Insert files in sequence, filling the root canal with sodium hypochlorite, and using a push-pull stroke with a circumferential motion
• Set rubber stops on files #40, #45, #50, etc., ½mm, 1mm, 1.5mm shorter than the working length, respectively

Important Reminders in Step-Back Technique

• ALWAYS WORK IN A WET FIELD
• IRRIGATE OFTEN
• RECAPITULATE OFTEN

Advantages and Disadvantages of Step-Back Technique

Advantages

• Better tactile awareness
• Keeps apical preparation small in its original position with a gradual taper
• Ability to prepare a proper apical stop

Disadvantages

• Chances of pushing debris into periradicular tissues
• Tendency to straighten the curved canal
• Time-consuming
• Difficult to insert instruments in canal

Types of Step-Back Technique

• Modified Step-Back Technique
  • Preparation is completed in apical third of the canal
  • Procedure is started 2-3 mm short of minor diameter/apical constriction for parallel retention form at apical area
• Passive Step-Back Technique
  • Combination of hand and rotary instruments for adequate coronal flare and apical part preparation
  • Provides gradual enlargement of the root in an apical to coronal direction
  • Reduces procedural errors like transportation of the canal, ledge, or zip formation