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Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition
Published on: February 23, 2024
Relationship between initial crowding and interproximal force during retention phase.
1Division of Applied Oral Sciences, Nihon University Graduate School of Dentistry, Tokyo, Japan. ohashi-km@dent.nihon-u.ac.jp
Journal of Oral Science
|July 1, 2010
Summary
Interproximal force (IPF) in lower front teeth increases during orthodontic retention, potentially indicating relapse. Severe pre-treatment crowding correlates with higher IPF, highlighting the need for careful monitoring.
Area of Science:
- Orthodontics
- Dental Biomechanics
Background:
- Orthodontic treatment aims to correct dental crowding and improve alignment.
- Maintaining tooth position after active treatment (retention phase) is crucial to prevent relapse.
Purpose of the Study:
- To investigate changes in interproximal force (IPF) in mandibular anterior teeth during orthodontic retention.
- To examine the relationship between the initial irregularity index and IPF.
- To assess the influence of erupting third molars on IPF.
Main Methods:
- Forty patients who underwent orthodontic treatment with bicuspid extraction were monitored for 18 months during retention.
- Interproximal force (IPF) was measured using a metal strip withdrawal method on mandibular anterior teeth.
- The irregularity index was calculated from initial dental casts.
Main Results:
- Total IPF significantly increased throughout the 18-month retention period.
- A positive correlation was observed between the initial irregularity index and total IPF from 6 to 18 months post-treatment.
- Erupting third molars did not demonstrate a significant effect on total IPF.
Conclusions:
- Increased IPF during retention may serve as an early indicator of mandibular anterior teeth relapse.
- Orthodontists should closely monitor patients with severe pre-treatment anterior crowding for potential relapse, especially after 6 months of retention.
