A gap that has always been present and one that has just appeared require different analysis. If your teeth seem to be moving apart, have the change checked before trying to bring them together with an appliance or exercises. Examination considers gums and bite as well as the visible space.
Long-standing, recent or returning after treatment?
To prepare for the check, establish how long you have noticed the gap. An older photograph, orthodontic treatment records or the date a retainer changed can help reconstruct the timeline.
Do not conclude that things have worsened from two photographs taken with different lighting or angles. Describe what alerted you: trapped food, changed contact between teeth, discomfort or simply a changed smile. The practitioner will decide how to measure and compare the situation.
Which signs warrant dental examination?
A new gap associated with mobility, bleeding or gum changes warrants examination. France's Assurance Maladie describes tooth mobility and new spaces among possible signs of periodontitis. They should not be masked by attempting aesthetic closure. Assurance Maladie guidance.
A check is also useful if your retainer no longer fits as before or a wire seems detached. Bring the appliance to the appointment. Do not force a removable retainer to try to move teeth back.
Why identify the cause before closing the gap?
Relative tooth size, a missing tooth, the bite and supporting tissues may contribute. The AAO distinguishes several situations that lead to different choices. AAO: dental spacing.
The plan should specify what will be corrected and what needs care alongside it. Visually closing a gap does not automatically address why it appeared.
If you mainly want to understand closure of a long-standing gap between incisors, see dental diastema: should the gap be closed?. This page focuses more on a change that needs checking.
Can tongue retraining bring teeth together?
The tongue and lips help balance pressures around teeth. This does not attribute every new gap to the tongue or establish that an exercise can close it. Proffit's theoretical paper also describes the possibility of swallowing adapting to the bite. Proffit, 1978
Tongue work may be discussed if a functional difficulty is identified. Reviews do not support promising orthodontic correction through retraining alone. Homem et al., 2014
A standard appliance such as Myoforce, priced at €50, should therefore not be chosen as an independent gap-closing device. Its purpose is tongue retraining within an appropriate approach.
After orthodontics: have the retainer checked
Teeth can change after treatment, explaining the role of retention and its checks. The Cochrane review compares methods without identifying an ideal device for every patient. Martin et al., 2023
If a gap returns, ask whether the retainer is intact, still fits correctly and whether another problem contributes. A retainer maintains a result; it should not be used to improvise renewed active tooth movement.
- Keep the appliance and previous instructions for the appointment.
- Specify how long the change has been visible.
- Report bleeding, pain or mobility.
- Ask about the possible role of a tongue assessment without replacing the orthodontic check.
Sources and method
- Assurance Maladie. Understanding gingivitis and periodontitis, accessed 1 October 2026.
- American Association of Orthodontists, 26 June 2026. Dental spacing, causes and options.
- Proffit, 1978. Pressure equilibrium and tooth position: theoretical paper.
- Homem et al., 2014. Systematic review of myofunctional therapy in orthodontics.
- Martin et al., Cochrane, 2023. Retention after orthodontic treatment.
Written by: Dr Vladimir Khourda, a dentist who no longer practises. Informational content updated on 1 October 2026 using the references cited. It does not replace an individual assessment.