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Updated: Feb 5, 2026

In Silico Clinical Trials for Cardiovascular Disease
Published on: May 27, 2022
Short-term morphological changes of vacuum-formed retainers with different gingival margin designs: a randomized
Objectives:
To investigate the morphological and dimensional changes in vacuum-formed retainers (VFRs) after intraoral aging of 3 months and 6 months and to compare changes between VFRs with conventional and modified gingival margin design.
Materials And Methods:
Forty-one patients were randomly assigned to two groups: conventional design (CD) and modified design (MD). Preuse and postuse digital models of each VFR were imported to Geomagic Control software to assess the morphological and dimensional changes.
Results:
In vivo, VFRs underwent significant changes over time. After 3 months, slight expansion of the VFRs was detected, while after 6 months, slight contraction was observed, despite not all parameters resulting in statistically significant differences. No statistically significant differences were found between the CD and MD groups.
Conclusions:
Intraoral aging affects the dimensional stability of VFRs. The gingival margin design did not impact the morphological and dimensional stability of VFRs over the observed period.
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