Orthodontic Retraction Basics: When and How to Start the Space Closure Phase

Orthodontic retraction is often misunderstood as simply “pulling the front teeth backward.” In reality, it is one of the most delicate and technique-sensitive phases in fixed appliance therapy. Before initiating retraction, the clinician must ensure proper alignment, leveling, and torque control—failing which the outcome can be compromised, both functionally and esthetically.

Orthodontic retraction requires torque to be preserved from the very beginning.

Orthodontic retraction wire sequence from NiTi to stainless steel for proper space closure
Illustration of wire progression before initiating orthodontic retraction.

🧭 Understanding the Timing of Retraction

Retraction should never begin immediately after bracket bonding. Instead, it must follow complete alignment and leveling. If space closure is attempted too early—before establishing a stable archwire platform—the risk of side effects like bowing, torque loss, anchorage loss, and root divergence increases significantly.

Signs that the case is ready for retraction include:

  • The curve of Spee has been flattened
  • Anterior torque is maintained without flaring
  • Rotations and crowding are fully resolved
  • The archwire has sufficient stiffness to resist deformation

In other words, retraction begins only when the system is “quiet”—mechanically stable and biologically ready.


🧵 Wire Sequence and Final Setup

Proper wire sequencing is essential. Most protocols follow this general path:

Round NiTi → Rectangular NiTi → Rectangular Stainless Steel

Retraction should only be performed on the final stainless steel wire, which acts as a rigid track to direct tooth movement efficiently.

  • For 0.018″ slot systems, a minimum of 0.017×0.025 SS is recommended.
  • For 0.022″ slot systems, use 0.019×0.025 SS or larger.

Initiating retraction on a flexible NiTi wire is a common mistake that can lead to uncontrolled tipping and loss of anterior torque.


⚙️ Anterior Torque in Orthodontic Retraction: Why It Matters

Maintaining anterior torque is essential for both function and esthetics. Patients don’t want their incisors to “lean backwards”—this not only affects smile appearance but can also create speech issues and tongue-space problems.

Torque loss during retraction is often due to:

  • Inadequate wire stiffness
  • Poor bracket positioning
  • Force vector misalignment

Clinical pearl:

“The wire is your track. If it’s warped, don’t send the train.”

Before retracting, verify torque expression—especially in the maxillary central incisors. Once retraction starts, recovering torque becomes significantly more difficult.


🧪 Common Pitfalls in Early Retraction

MistakeConsequence
Retracting on NiTi wiresLoss of control, flaring
Incomplete levelingBowing of archwire
Ignoring torqueAnterior collapse
Premature space closureAsymmetric tooth movement, anchorage loss

✅ Takeaway Summary

  • Retraction begins after leveling and alignment—not before.
  • Final archwire must be rectangular stainless steel for adequate control.
  • Torque is not optional—check it before retraction.
  • Move slowly, observe biologic response, and adjust accordingly.
  • To summarize: orthodontic retraction is not just a mechanical step—it’s a biologically sensitive, timing-critical phase that requires careful setup

Coming up next:
Loop Mechanics vs Sliding Mechanics – choosing the right tool for the right case.

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