Can Compromised Incisors Survive Open Bite Closure?

Straight Talk draws its cases and discussions from the Orthotown message boards. Written by the editorial team with the assistance of AI, each article showcases how orthodontists tackle unusual and challenging scenarios.

A 27-year-old woman presented with a severe anterior open bite and a difficult orthodontic history. As a teenager, she had been treated by a general dentist who extracted all four second molars. She disliked the braces so much that she removed them herself, and cement remnants were still on her teeth years later. Her third molars had since erupted into the second molar spaces with significant tipping, and her maxillary incisors showed 2+ mobility. Other providers had told her the incisors had severe root resorption and would likely be lost (Figs. 1–11).

Fig. 1: Initial intraoral photos.

Fig. 2: Initial panoramic radiograph.

Fig. 3: Progress intraoral photos at one year (aligner 26).

She asked about Invisalign. The treating orthodontist agreed to try, explained that the tipped third molars could not be fully uprighted, and discussed the risks, including the possibility of losing the incisors, documenting those concerns in her informed consent. He chose not to take a CBCT. The patient had accepted that she might lose the incisors, and if implants became necessary, extrusion during treatment could help develop bone at those sites.

The plan was conservative by design. Given the compromised condition of the incisors, the treating orthodontist slowed tooth movements by 50%. At the one-year progress appointment, something unexpected had happened: The incisors were becoming less mobile despite continued tooth movement. The open bite had also closed to approximately 2 mm of overbite, with no posterior open bites. By a subsequent assessment, the mobility had resolved entirely. Equilibration was needed to reduce fremitus on the laterals, a problem few would expect in a case that started with a severe open bite.

Fig. 4: Progress panoramic radiograph at one year.

Fig. 5: Progress intraoral photos at the additional aligner scan.

Fig. 6: Progress lateral cephalogram.

The patient, meanwhile, had a different priority. She was focused on her midlines. Correcting the discrepancy would have required unilateral IPR on the lower arch, which she declined. It was a familiar reminder that the outcome a clinician considers remarkable is not always the one the patient notices.

Retention drew as much interest as the treatment itself. The patient wore her final aligners at night until lab-fabricated clear retainers were made from a final scan, along with printed models she could use for future replacements.

The bigger shift was in philosophy. Rather than delivering retainers and hoping the open bite holds, the treating doctor has placed responsibility on the patient. She has been instructed to close her teeth together and swallow twice an hour, making sure the front teeth touch, and to call immediately if they stop.

In his experience, open bites managed this way tend to deepen over time, and aligner-treated open bites in particular seem to improve in retention rather than relapse. At the six-month retention check, the result was holding well. The treating orthodontist also shared photographs at 12 months post-treatment and confirmed that the patient continued wearing Essix retainers at night.

Colleagues added context. One Townie suggested that vacuum-formed retainers may contribute to stability by acting as a posterior bite plate. Another asked about etiology and when myofunctional therapy should be part of the plan. The patient had a thumb habit until age 14, and the treating doctor evaluates swallow pattern and tongue posture at all initial exams, prescribing myofunctional exercises for every open bite patient.

Fig. 7: Cephalometric comparison.

Fig. 8: Final records.

Fig. 9: Panoramic comparison, initial and final.

Fig. 10: Six-month retention check, frontal view.

Fig. 11: Intraoral photos at 12 months post-treatment.

Two diagnostic questions remained open. The first involved the tipped mandibular third molars. They were uprighted somewhat, but whether their residual angulation and mesial contacts raise long-term periodontal risk is unclear. The second involved root length. The maxillary incisor roots appeared short on the ceph, not just the pano. One contributor offered a likely partial explanation: The centrals were angled in the initial records, crowns distal and roots mesial, which could produce foreshortening on a lateral ceph. That alone probably does not account for all of the apparent shortening, leaving open the question of how much true resorption existed and how much was projection.

The case brings orthodontists to a familiar crossroads, but with an unusual twist. When incisors are mobile, roots appear severely resorbed, and the patient has been told to expect tooth loss, is cautious, slowed aligner treatment a reasonable path to saving them? Or does this case challenge conventional thinking about how much compromised teeth can tolerate and what orthodontists might accomplish when the prognosis seems anything but promising?

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