Objective evaluation of compliance after orthodontic treatment using Hawley or vacuum-formed retainers: A 2-center randomized controlled trial over a 3-month period.

Introduction: The aim of this 2-arm parallel trial was to assess patient compliance objectively with Hawley or vacuum-formed retainers in the maxillary arch in a 3-month period after active orthodontic treatment through the use of the thermosensitive microsensor TheraMon.

Methods: Patients who had just completed orthodontic treatment in the Postgraduate Orthodontic Clinic, School of Dentistry, National and Kapodistrian University of Athens and in a private orthodontic practice were randomly allocated to either the Hawley or vacuum-formed group for retention. Eligibility criteria included patients aged 12-18 years who had undergone orthodontic treatment in both arches for ≤ 5 years.