It is possible to get braces on only the top teeth, a treatment approach known as single-arch treatment. This method limits orthodontic work to one dental arch, the upper arch, instead of both the upper and lower teeth. While it may seem like a simpler or faster option, single-arch treatment is only appropriate in a limited number of specific circumstances. The successful outcome of any orthodontic treatment relies on achieving a stable and coordinated bite, which means the upper and lower teeth must fit together properly.
Criteria for Single-Arch Treatment
Orthodontists consider single-arch treatment when issues are minor and confined to the upper teeth. This approach is often reserved for small cosmetic adjustments where the lower teeth and the overall bite relationship are already well-aligned and stable. A patient might be a candidate if they require a minor correction, such as fixing a slight shift in the upper teeth following previous orthodontic work.
The ideal scenario involves minimal crowding, typically affecting only one or two teeth, or the need to close minor gaps, known as diastemas, in the upper arch. Crucially, the existing bite, or occlusion, between the back molar and premolar teeth must be healthy and balanced. If this posterior bite relationship is stable, moving only the front upper teeth for aesthetic reasons can be done without disrupting overall jaw function.
Treating only the top arch must not negatively affect how the upper teeth meet the lower teeth when biting and chewing. Any planned tooth movement must be small enough that the final position of the upper teeth maintains proper contact with the stationary lower teeth. The decision depends heavily on a comprehensive assessment confirming the lower arch is already in a satisfactory position.
Appliance Options and Treatment Mechanics
A variety of appliances can be used for single-arch treatment, depending on the required tooth movements and aesthetic preferences. Traditional metal braces, ceramic braces, and lingual braces are viable options for the upper arch. Lingual braces are placed on the tongue-side of the teeth, making them virtually invisible from the front, and are often preferred for cosmetic corrections.
Clear aligners, such as those used in systems like Invisalign, are also frequently used for minor single-arch adjustments, offering a removable and less noticeable alternative. The core mechanical goal is to move the teeth within the upper arch without changing its overall shape or size in a way that would interfere with the lower arch. The force applied is controlled to ensure teeth move to their desired positions without causing unwanted shifts in the lower teeth.
Orthodontic mechanics focus on applying gentle, continuous pressure to reposition teeth, relying on the biological response of the bone surrounding the tooth roots. For limited movement, treatment may focus only on the front six to eight teeth, using the back teeth as stable anchors. This localized application of force minimizes the risk of unintended changes to the stable back bite.
When Single-Arch Treatment is Not Recommended
The decision to treat only one arch is complex because the jaw functions as a coordinated unit, and a change in one arch inevitably affects the other. Single-arch treatment is not recommended in cases of moderate to severe crowding or significant bite issues. This includes situations involving a substantial overjet (horizontal overlap), an underbite, a crossbite, or an open bite, all of which require coordinated movement of both arches for correction.
Attempting to correct significant misalignment in only the upper arch can lead to a condition known as iatrogenic malocclusion, meaning the orthodontic treatment itself creates a bite problem. For instance, if crowded upper teeth are straightened, they tend to shift forward. This movement can worsen an existing overbite or even create one where none existed before, leading to an unstable bite relationship where the upper and lower teeth do not align correctly.
An unstable bite can cause excessive wear on the teeth due to uneven pressure and the development of pain in the temporomandibular joint (TMJ). In some cases, single-arch movement can result in a posterior open bite, where the back teeth no longer touch, making chewing difficult and inefficient. Treating only one arch initially may save time and money in the short term but often leads to the need for comprehensive, full-arch treatment later to fix the resulting instability.
Orthodontic assessment always considers the relationship between the two arches because the long-term health and stability of the teeth depend on a balanced bite. If a patient’s condition requires any major tooth movement or correction of a jaw-related discrepancy, a full treatment plan addressing both arches is necessary to ensure a functional and lasting result.