Dr. David Kennedy, orthodontist, at the faculty of dentistry at UBC spoke with Dr. Chiraz Guessaier about the correction of transverse posterior crossbites.
In patients with posterior crossbites, early treatment will frequently permanently correct the condition. A posterior crossbite with a functional shift left untreated can lead to some adaptive growth changes. Additionally, managing this condition later on is often more difficult to treat.
The most common posterior crossbite is one in which there is a unilateral presentation and there is a functional shift of the mandible. This constitutes ~80-90% of crossbites that are seen.
- Detectable functional shift
- Unilateral presentation of the crossbite
- Midline shift in direction of the crossbite
- Can be related to extended digit-sucking habits
- Associated with upper airway obstruction and inability to breathe through the nose
- Genetic predisposition
Observation: If left untreated in adults, there is significant adaptation in the TMJ on the non-crossbite side and there is limited self-correction, facial asymmetry, mandibular development is warped and this makes future surgical correction very difficult.
Equilibration: Selective equilibration as a treatment strategy is limited and is best for the primary dentition.
Expansion: Expansion with a fixed or removable appliance has a higher success rate. Fixed appliances have a higher success rate than removable appliances as compliance is higher.