Miniscrew-assisted rapid palatal expander (MARPE): the quest for pure orthopedic movement

Abstract

The midpalatal suture has bone margins with thick connective tissue interposed between them, and it does not represent the fusion of maxillary palatal processes only, but also the fusion of palatal processes of the jaws and horizontal osseous laminae of palatal bones. Changing it implies affecting neighboring areas. It has got three segments that should be considered by all clinical analyses, whether therapeutic or experimental: the anterior segment (before the incisive foramen, or intermaxillary segment), the middle segment (from the incisive foramen to the suture transversal to the palatal bone ) and the posterior segment (after the suture transversal to the palatal bone ). Rapid palatal expansion might be recommended for patients at the final pubertal growth stage, in addition to adult patients with maxillary constriction. It represents a treatment solution that can potentially avoid surgical intervention. When performed in association with rapid palatal expanders, it might enhance the skeletal effects of the latter. Of the various designs of expansion appliances, MARPE (miniscrew-assisted rapid palatal expander) has been modified in order to allow its operational advantages and outcomes to become familiar in the clinical practice.

<p><strong>Reliability of Orthodontic Miniscrews: Bending and Maximum Load of Different Ti-6Al-4V Titanium and Stainless Steel Temporary Anchorage Devices (TADs).</strong></p>

“…The mean bending values at 0.1-mm deflection ranged between 31-58 N, whereas at 0.2-mm deflection, forces ranged between 43-116 N. All of these values are generously above the values reported during conventional clinical applications, which have been reported to be approximately under 5 N [37]. However, when miniscrews are used for non-conventional applications, fracture risk could increase, as miniscrews would be subjected to higher forces if compared with conventional orthodontic anchorage uses [10][11][12], even if no reports have evaluated this amount yet.…”

“…Several reports showed the use of miniscrews for space management [3], intrusion [4], extrusion [5], the retraction of anterior teeth [6], crossbite correction [7], and sliding mechanics [8]. The use of temporary anchorage devices (TADs) has been reported also for non-conventional purposes, as stabilization for facemask protraction [9], fracture management [10], palatal skeletal expanders [11], and provisional miniscrew-supported pontics [12].…”

Description of a Digital Work-Flow for CBCT-Guided Construction of Micro-Implant Supported Maxillary Skeletal Expander

“…The use of skeletal anchorage is getting widespread among orthodontists since it facilitates the management of complex orthodontic biomechanics; as a consequence, skeletal anchorage can be useful in treating borderline cases such as transversal maxillary deficiency in adults. In this respect, miniscrews-assisted rapid maxillary expansion was found to effectively open the mid-palatal suture in adults without the necessity to undergo orthognathic surgery [12,24,[28][29][30][31][32][33][34][35][36][37].…”

Expansión rápida maxilar asistida con microimplantes

“…Además, a este examen previo a la ERM le podríamos adicionar un disyuntor que no solo se apoye en dientes sino también en hueso, muy usado por Won Moon: el MARPE (expansión palatina rápida asistida con microimplantes) 5,6 . Entre sus muchas variantes, puede ser desarrollado colocando cuatro microimplantes ortodóncicos a los costados de la sutura media palatina con una separación aproximada de 2 a 3 mm de esta en busca de anclaje bicortical 7 para mejorar su retención primaria y así poder vencer la resistencia que ofrecen las interdigitaciones cada vez más complejas que ofrece la sutura palatina con el paso del tiempo y las suturas circunmaxilares (Figura 2).…”