Orthodontic Treatment for Adolescents

A narrow upper jaw is a common finding in adolescent patients and can contribute to crowding, crossbites, breathing difficulties, and sleep-disordered breathing. Palatal expansion widens the upper jaw by gradually separating the midpalatal suture — the growth plate running along the centre of the palate — and allowing new bone to form in the space created.

In younger children, the suture is wide open and responds well to conventional tooth-borne expanders. However, by the mid-teenage years, the suture begins to fuse and becomes progressively less responsive to tooth-borne expansion forces. In these patients, conventional expanders are less effective — they tend to produce dental tipping and tooth movement rather than the genuine skeletal expansion needed.

For adolescent patients whose suture is no longer fully responsive to tooth-borne expansion, MARPE (Miniscrew-Assisted Rapid Palatal Expansion) offers a bone-anchored alternative that bypasses the teeth entirely and delivers expansion forces directly to the palatal bone — achieving true skeletal widening of the upper jaw even when conventional approaches would fall short.

Why Conventional Expanders Are Less Effective in Older Adolescents

A traditional tooth-borne palatal expander works by pushing outward against the upper back teeth, which transmit that force to the surrounding bone and suture. In young children, where the suture is open and the bone is responsive, this works well.

As adolescence progresses and the suture begins to interdigitate and ossify, the resistance to expansion increases significantly. Tooth-borne forces are increasingly absorbed by the teeth themselves rather than transmitted to the suture, resulting in dental tipping (the teeth tilting outward) rather than the jaw actually widening. This not only limits the effectiveness of treatment but can also compromise the positions of the anchor teeth.

MARPE eliminates this problem. By anchoring the expander to the palatal bone using four small titanium miniscrews (temporary anchorage devices), expansion forces bypass the teeth entirely and act directly on the suture. This allows genuine skeletal expansion to occur even in patients where a conventional expander would no longer be effective.

How MARPE Works

A bone-anchored palatal expander is secured to the palate using four small titanium miniscrews placed directly into the palatal bone under local anaesthetic. The miniscrews are temporary — they are removed once expansion is complete and the bone has consolidated.

The expander is activated by turning a small key inserted into an activation hole, typically once or twice daily for a defined period. As the expander is turned, the two halves of the device move apart, applying a gradually increasing force to the midpalatal suture. Over time, the suture separates and new bone forms in the gap — widening the dental arch, expanding the nasal base, and improving nasal airway volume.

A small gap between the upper front teeth is normal during the active expansion phase — this is a sign that the suture is opening and is expected. The gap closes naturally as the bone consolidates following the end of active expansion.

What MARPE Can Achieve in Adolescents

Dental arch widening — correcting a narrow upper arch, resolving posterior crossbites, and creating space to reduce or eliminate crowding.

Nasal airway improvement — widening the upper jaw widens the nasal floor and increases the volume of the nasal airway, which can significantly improve nasal breathing in adolescents who are habitual mouth breathers due to nasal constriction.

Support for sleep-disordered breathing — in adolescents with sleep-disordered breathing related to a narrow upper airway, MARPE can be a meaningful component of a broader management plan.

Improved foundation for subsequent treatment — where crowding or crossbite is present, expansion creates the space and arch width needed for more efficient and stable tooth alignment with fixed braces or aligners.

After Expansion

Following the active expansion phase, the expander is left in place for a consolidation period — typically three to six months — to allow the new bone to mature and stabilise. The expander is then removed, and fixed braces or clear aligners are used to align the teeth within the expanded arch.

In many cases, the combination of MARPE followed by fixed brace or aligner therapy produces a more comprehensive and stable result than tooth alignment alone would have achieved.

Myofunctional Therapy Following Expansion

In selected adolescent patients, abnormal tongue posture or oral habits — such as a low resting tongue position or a tongue thrust swallowing pattern — are identified as part of the orthodontic assessment. These patterns are particularly common in adolescents who have been habitual mouth breathers, and they can limit the long-term stability of palatal expansion if not addressed, as the tongue plays an important role in maintaining arch width from the inside.

Where these habits are present following expansion, myofunctional therapy can be a valuable addition to the overall treatment plan. By retraining the tongue and surrounding muscles to function in a more optimal pattern, it supports the skeletal changes achieved through expansion and helps to establish healthier breathing and swallowing habits for the long term.

While myofunctional therapy is not offered at Lusk Orthodontics directly, we collaborate with experienced myofunctional therapists in Ireland and the UK, and are able to coordinate referral and ongoing communication where this forms part of a patient’s care.

Book a Consultation

To find out whether MARPE palatal expansion is appropriate for your teenager, book a specialist assessment at Lusk Orthodontics, including a review of current imaging.