Abstract
BackgroundThe purpose of this study was to compare the stress distribution and displacement patterns of the one versus two maxillary molars distalization with iPanda and to evaluate the biomechanical effect of distalization on the iPanda using the finite element method.MethodsThe finite element models of a maxillary arch with complete dentition, periodontal ligament, palatal and alveolar bone, and an iPanda connected to a pair of midpalatal miniscrews were created. Two models were created to simulate maxillary molar distalization. In the first model, the iPanda was connected to the second molar to simulate a single molar distalization. In the second model, the iPanda was connected to the first molar to simulate “en-masse” first and second molar distalization. A varying force from 50 to 200 g was applied. The stress distribution and displacement patterns were analyzed.ResultsFor one molar, the stress was concentrated at the furcation and along the distal surface in all roots with a large amount of distalization and distobuccal crown tipping. For two molars, the stress in the first molar was 10 times higher than in the second molar with a great tendency for buccal tipping and a minimal amount of distalization. Moreover, the stress concentration on the distal miniscrew was six times higher than in the mesial miniscrew with an extrusive and intrusive vector, respectively.ConclusionsIndividual molar distalization provides the most effective stress distribution and displacement patterns with reduced force levels. In contrast, the en-masse distalization of two molars results in increased force levels with undesirable effects in the transverse and vertical direction.
Highlights
The purpose of this study was to compare the stress distribution and displacement patterns of the one versus two maxillary molars distalization with indirect Palatal Anchorage and Distalization Appliance” (iPanda) and to evaluate the biomechanical effect of distalization on the iPanda using the finite element method
Two set-ups models of molars distalization with iPanda were constructed to simulate maxillary molar distalization: In the first model, the iPanda was connected to the second molar to simulate a single molar distalization (Fig. 1a)
The iPanda was connected to the first molar to simulate the enmasse of the first and the second molar distalization (Fig. 1b)
Summary
The purpose of this study was to compare the stress distribution and displacement patterns of the one versus two maxillary molars distalization with iPanda and to evaluate the biomechanical effect of distalization on the iPanda using the finite element method. Maxillary molar distalization has become an important approach for the treatment of class II malocclusions. It allows the movement of first molars to occlude into a class I relationship, facilitating the correction of crowding and reducing the overjet [1, 2]. Several tooth-borne distalizing devices have been introduced to correct class II malocclusion [3]. Undesirable dental anchorage loss, represented by the Successful distalization of the maxillary first molar alone, before the eruption of the second molar in young patients, has been reported by several authors [6]. In adult patients, the distalization of the maxillary first molar alone is only possible followed by the distalization of the second molars or extraction of the second molars [7].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
