Narrow Arches Diagnosis Treatment

This guide organises possible treatment options for a narrow arches diagnosis. The document is a treatment planning tool to assist you assist how to best treat patients. Treatments are graded by complexity, ranked by the orthodontic technique required, as a guide to the efficacy of treatment and enable providers to select cases that best matches their ability to apply advanced techniques. In this regard, it is particularly useful for dentists who are just beginning to provide clear aligner treatment.

Disclaimer

As doctors are solely responsible for the treatment they’re providing their patients, they should understand their limits and not hesitate to consult a specialist for further guidance when required. Note when applying this guide only general, high-level information on how each isolated condition might be treated is provided. The relationships between different conditions that exist in the majority of patients are not addressed. In this regard, always consider each patient’s individual dental and periodontal condition, restorative needs, facial proportions, and age when considering treatment options.

Narrow Arches

Narrow Arches

Narrow arches are characterised by arches that are tapered rather than broad and U-shaped. Narrow arches can occur in the presence or absence of a posterior crossbite. From the anterior view, an aesthetic smile is one where the bicuspids and the first molar can be seen in a full smile. In a case with narrow arches, the upper posterior teeth cannot be seen in the smile and the teeth are usually inclined lingually. Narrow arches can be broadened to improve the arch form and improve a smile, provided that adequate periodontal support is present to allow healthy dental expansion.

When programming dental posterior expansion, expand the posterior segment as a unit (for example from the cuspid to the second molar and also bilaterally if possible). Prior to progressing to the next stage, make sure the existing aligner is fully seated and the teeth have moved to the projected position. You can request attachments on the bicuspids to help anchor the aligners.

Increasing the time interval between aligners to three weeks may be indicated. During expansion, monitor the level of the buccal tissue in the posterior segment. Regularly examine the periodontium and also run a finger across the buccal area to ensure the roots are not being over-expanded at each appointment.

Check for open bite tendency as the teeth are being expanded. Lingual interferance can result in an occlusal prematurity that prevents complete bite closure.

Dental

• Both Arches

Expansion Novice (0-15 cases)

Dental posterior expansion of 2–3 mm per side is predictable and achievable with Proligner. As a general guideline, look at the buccal bone in the posterior segment to determine if the case can be expanded dentally. The limiting factor in the level of dental expansion is the amount of buccal bone available and also the overlying periodontium. If there is bone loss or recession in the area, it would be advisable not to expand dentally in these cases. If the teeth are inclined lingually and the amount of buccal bone and periodontium is sufficient then dental expansion is a good treatment option in cases with narrow arches.

• Single Arch

Expansion Novice (0-15 cases)

Dental posterior expansion of 2–3 mm per side is predictable and achievable with Proligner. As a general guideline, look at the buccal bone in the posterior segment to determine if the case can be expanded dentally. The limiting factor in the level of dental expansion is the amount of buccal bone available and also the overlying periodontium. If there is bone loss or recession in the area, it would be advisable not to expand dentally in these cases. If the teeth are inclined lingually and the amount of buccal bone and periodontium is sufficient then dental expansion is a good treatment option in cases with narrow arches.

Expansion and/or constriction of other(s) Experienced (16-50 cases)

Dental posterior expansion of 2–3 mm per side is predictable and achievable with Proligner. As a general guideline, look at the buccal bone in the posterior segment to determine if the case can be expanded dentally. The limiting factor in the level of dental expansion is the amount of buccal bone available and also the overlying periodontium. If there is bone loss or recession in the area, it would be advisable not to expand dentally in these cases. If the teeth are inclined lingually and the amount of buccal bone and periodontium is sufficient then dental expansion is a good treatment option in cases with narrow arches.

Skeletal

• Unfused Maxilla (Teen)

Maintain narrow arches, aesthetic alignment Novice (0-15 cases)

A limited treatment option is to use Proligner for aesthetic alignment of the anterior teeth while maintaining the narrow arches.

Rapid palatal expansion followed by Proligner for alignment Advanced (>50 cases)

Skeletal expansion is not achievable with Proligner alone. Proligner may be used for alignment following surgical expansion. For some teen patients, non-surgical rapid palatal expansion followed by Proligner treatment may also be an option.

• Fused Maxilla (Adult)

Maintain narrow arches, aesthetic alignment Novice (0-15 cases)

A limited treatment option is to use Proligner for aesthetic alignment of the anterior teeth while maintaining the narrow arches.

Surgical expansion followed by Proligner for alignment Advanced (>50 cases)

Skeletal expansion is not achievable with Proligner alone. Proligner may be used for alignment following surgical expansion. For some teen patients, non-surgical rapid palatal expansion followed by Proligner treatment may also be an option.