The Behavior of Two Types of Upper Removable Retainers—Our Clinical Experience

Abstract

The Hawley retainer (HR) and the vacuum-formed retainer (VFR) are the most common removable retainers in orthodontic treatments. The aim of this retrospective study was to comparatively analyze the behavior of two types of removable retainers—HRs and VFRs—in terms of retainer damage, loss, and the rate of installation of mild or severe relapse that required recourse to certain therapeutic interventions. The study was performed on 618 orthodontic patients aged 11–17 years, average age 13.98 ± 1.51, out of which 57% were patients having VFRs and the remaining 43% having HRs in the upper arch. We performed an analysis of the two groups of patients—HRs group and VFRs group—at 6 months (T1) and at 12 months (T2) after the application of the retainer. The results showed that 6% of all the retainers were damaged, mostly at T2 (54.1%). Seven percent of all the retainers were lost, mostly at T1 (58.1%). Of all the patients, 9.1% presented mild relapse, mostly at T1 (58.9%), while 2.6% presented severe relapse. The VFRs were significantly more frequently associated with the occurrence of damage than the HRs (p < 0.001). Severe relapse was more frequently associated with the HRs rather than with VFRs (p < 0.05).

A Case Report of Caries Incident in a Patient Wearing an Essix Type Retainer.

“…Another study presented that Essix materials used for the thermoplastic retainers are the following: polypropylene polymer-based material, polyethylene copolymers, and polyethylene terephthalate glycol copolymer (a thick sheet material). Regularly, the thicknesses of Essix between 0.75 mm and 1 mm (Vaida et al 2020).…”

Surgical-Orthodontic Diagnosis and Treatment Planning in an Asymmetric Skeletal Class III Patient—A Case Report

“…Nonetheless, a thermoplastic/essix retainer could be used instead of a Hawley retainer. Despite both devices being equally good in terms of treatment retention, the thermoplastic retainer over time becomes less resistant [34].…”

Chronological Age in Different Bone Development Stages: A Retrospective Comparative Study

“…The CVM method seems to be able to replace the hand and wrist radiography for the estimation of bone development and can be used with confidence for this purpose [14,15]. Moreover, lateral cephalometric radiographs can be used to establish various orthodontic diagnoses [12,16], as well as to assess the morphology of other bone structures in the craniofacial region [17]. Mandibular growth can also be safely and correctly assessed on lateral cephalometric radiographs [18].…”