Wir verwenden Cookies, um für diese Website Funktionen wie z.B. Login, einen Warenkorb oder die Sprachwahl zu ermöglichen. Weiterhin nutzen wir für anonymisierte, statistische Auswertungen der Nutzung Google Analytics, welches Cookies setzt. Mehr Informationen finden Sie in unserer Datenschutzerklärung.
OK, ich bin einverstanden Ich möchte keine Google Analytics-Cookies
Journal of Aligner Orthodontics
Login:
Benutzername:

Kennwort:

Plattform:

Kennwort vergessen?

Registrieren

Journal of Aligner Orthodontics 2 (2018), Nr. 4     21. Jan. 2019
Journal of Aligner Orthodontics 2 (2018), Nr. 4  (21.01.2019)

Seite 295-304, Sprache: Englisch


Recommendation of a novel film-thickness sequence, 0.4, 0.5 and 0.75 mm, for aligner systems
Elkholy, Fayez / Lapatki, Bernd G.
Objectives: For experimental evaluation of sequential aligner systems, the conventional sequence of aligner thickness (0.5 to 0.8 mm) and a novel sequence using thinner 0.4- and 0.3-mm films were investigated biomechanically in four mechanical in-vitro studies.
Materials and methods: The first two studies focused on determining mechanical loads exerted during labio-palatal translation of a maxillary central incisor and derotation of a mandibular canine when using aligners with conventional thicknesses of 0.5 to 0.75 mm. The third and fourth studies examined the mechanical load during different movements of a maxillary central incisor by use of 0.3- and 0.4-mm novel, thinner aligners. All experiments were performed on specifically designed test setups equipped with acrylic casts from which the corresponding measurement tooth was separated and mounted on a three-dimensional (3D) movement unit via a 3D force-moment (F/M) sensor.
Results: Even for small movements of < 0.5 mm and < 10 degrees, quite high F/M values, up to 8.4 N and 89.2 Nmm, respectively, were recorded for the 0.5-mm aligner. Use of aligners thermoformed from novel 0.4-mm film resulted in mean reduction in force and moment of 35% and 45%, respectively, for translation and rotation of the maxillary right central incisor (tooth 11). Aligners fabricated from 0.3-mm film showed insufficient form stability during repeated seating and removal from the test cast, and should therefore also be unsuitable for clinical application.
Conclusions: When using the thinnest 0.5-mm film, the risk of overloading the periodontal structures is quite high. Based on these in-vitro experiments, a novel aligner thickness sequence is recommended using 0.4-, 0.5- and 0.75-mm aligners. This sequence substantially reduces the F/M values exerted by the first and thinnest aligner and ensures relatively constant load increases for each individual setup step.

Schlagwörter: aligner sequence, aligner thickness, force, orthodontic aligner, overloading
Volltext (keine Berechtigung) einzeln als PDF kaufen (20.00 €)Endnote-Export