Lower Incisor Extraction: An Alternative Approach

The extraction of a lower incisor in orthodontics is uncommon and, in many instances, can hold a feeling of trepidation. It can be an excellent alternative to two premolar extractions with greater efficiency and reduction in treatment duration. A Kesling analogue setup or digital set-up can be useful in these cases for both the clinician and patient to visualise changes.

Indications

Class I Malocclusion

• Tooth size anomalies due to Bolton’s mandibular tooth excess

• Tooth size discrepancy in the upper arch mesio-distal width (undersized upper lateral incisors)

• Ectopically erupted incisors

• Anomalies in the number of lower anterior teeth

Class II Malocclusion

• Class II Division 1 skeletal and Dental malocclusion with lower crowding but where we want no / minimal lower labial segment retraction

“A kesling analogue setup or digital setup can be used for both the clinician and patient to visualise changes.”

Class III Malocclusion

• Mild class III malocclusion with an anterior crossbite

• Mild class III malocclusion with an edge to edge relationship / tendency to an open bite.

• Non-surgical alternative (camouflage) in mild class III skeletal cases which require mild overjet and overbite corrections

Other Indications

• Periodontally compromised mandibular incisor / recessions and bone loss

• Adult Orthodontics

• Carious / Root filled mandibular incisor

• Cases requiring minimal profile changes

• Retreatment cases where the intercanine width has been severely expanded and where IPR is not a sufficient alternative

• Temporomandibular disorders where a proper overjet and overbite is required for anterior guidance and occlusal stability

“Success is based upon correct case selection. This primarily is the analysis of tooth sizes and gingival biotype.”

What are the advantages of this approach?

1. Reduces treatment time

2. Mechanics can be simplified

3. Decreases the amount of tooth movement required compared to a premolar extraction alternative

4. Reduces the risk of anchorage loss as the posterior segments are untouched

5. Minimal profile changes

6. Posterior occlusion not disturbed significantly

What are the disadvantages of this approach?

1. Changes in the interproximal papilla which can lead to open embrasures or ‘black triangles’

2. Midline discrepancy is inevitable

3. Can cause a Bolton’s tooth size discrepancy if case not selected appropriately

4. During the orthodontics, the patient may have an aesthetic concern due to the extraction space (a pontic tooth can be placed)

5. The overjet may be slightly increased