Key takeaways
- Planned overbite correction is often only partly achieved, so plan with overcorrection and expect a refinement.
- Bite opening comes from several mechanisms, not just true incisor intrusion.
- Lower incisor intrusion is one of the less predictable movements and needs careful staging and anchorage.
- Send records that show the smile line and gingival display, and say which teeth you want intruded.
Why deep bites are challenging with aligners
Vertical control is one of the most demanding parts of aligner treatment. A 2025 systematic review comparing planned and achieved results found that achieved results matched only about 41.5% of the planned overbite correction in deep bite cases, compared with 62.1% in open bite cases.
Lower incisor intrusion, which deep bite correction often relies on, is particularly limited. Another 2025 systematic review reported mean lower incisor intrusion of 0.4 to 1.5 mm, with predictability between 35% and 65%. It concluded the movement is feasible when it is supported by careful biomechanical planning.
How overbite is actually reduced
When a deep bite opens, it is rarely through pure intrusion alone. Overbite reduction usually combines several of these:
- True intrusion of upper and/or lower incisors.
- Relative intrusion, where the incisors stay put while posterior teeth erupt or extrude.
- Proclination of incisors, which reduces overbite as the teeth tip forward.
- Levelling the curve of Spee in the lower arch.
Knowing which mechanism the plan relies on matters, because each has different limits and side effects. Proclination, for example, opens the bite but changes incisor inclination and arch length.
Planning tips that improve predictability
- Overcorrect. Because only part of the planned correction tends to be achieved, many protocols plan more overbite reduction than the final target.
- Stage intrusion in groups. Intruding fewer teeth at a time, with the rest acting as anchorage, gives the aligner more to push against.
- Use anchorage on posterior teeth. Attachments on premolars and molars help retention and vertical control while the anterior teeth intrude.
- Consider bite ramps. Ramps on the lingual of the upper incisors can disclude the posterior teeth and help bite opening, where the system supports them.
- Watch torque. When incisors are intruded and retracted together, check that the plan keeps their inclination where you want it.
- Follow your per-stage limits. Keep vertical movement per stage within your protocol rather than accepting the software default.
- Plan for a refinement. Tell the patient up front that deep bites commonly need one.
What to send with a deep bite case
- Full upper and lower scans and a reliable bite scan.
- Smile and profile photos, ideally showing incisor display at rest and when smiling.
- A lateral cephalogram if you have one, to judge incisor inclination and vertical pattern.
- Your prescription: which teeth to intrude, whether proclination is acceptable, and the overbite you are aiming for.
Checklist before you approve the plan
| Check | What to look for |
|---|---|
| Mechanism | Is the bite opening from intrusion, proclination or posterior extrusion, and is that what you want? |
| Overcorrection | Is extra correction built in where predictability is low? |
| Anchorage | Do the posterior teeth have attachments to hold them? |
| Incisor torque | Do the incisors keep a healthy inclination at the end? |
| Smile line | Does the final incisor position suit the patient's display and smile arc? |
References
- Boccuzzi M, Cosola S, Butera A, et al. Predictability of ClinCheck in overbite correction with aligners: a systematic review. Appl Sci. 2025;15(13):7268.
- Fracchia DE, Bignotti D, Lai S, et al. Predictability of lower incisor intrusion with clear aligners: a systematic review of efficacy and influencing factors. J Clin Med. 2025;14(17):6339.
This article is for dental professionals and is for general education only. It is not clinical advice for a specific patient. Treatment decisions remain the responsibility of the prescribing clinician. See our clinical disclaimer.