Angle Pearls Customizing Microimplant-Assisted Rapid Palatal Expander (MARPE) to Maximize Efficacy of Treatment Dr. Thomas Roblee San Francisco, CA Incorporating adjunct mechanics into a patient's microimplant-assisted rapid palatal expander (MARPE) design gives the practitioner the ability to address problems in all three planes of space at the beginning of treatment. It can also decrease chair time and eliminate the need for additional appliances. By capitalizing on the biomechanical advantage of skeletal anchorage provided by the MARPE along with the favorable biological conditions following expansion, treatment efficiency can be maximized with these customized appliances. The following MARPE intrusion technique is an excellent treatment option for simultaneous transverse and vertical correction. intrusion hooks were added to the MARPE and molar bands were used (Figure 3). 2. Following expansion, simply cut the support arms anchoring the molars and add power chains or NiTi springs to activate intrusion (Figure 4). If palatal tipping is a concern, adding a buccal microimplant or transpalatal arch can help achieve more pure bodily intrusion by maintaining molar angulation. 3. During the 6-month retention period following expansion, MARPE anchorage is used to stabilize the newly established vertical position of 1. The patient presented here had both skeletal and dental transverse discrepancy (Figures 1 and 2). Design the appliance so that minimal chair time is needed to activate the adjunct mechanics following expansion. In this design, Figure 3. Postexpansion: MARPE design includes hooks (green arrows) for easy transition to intrusion mechanics Figure 1. Pretreatment: maxillary occlusal view Figure 2. Pretreatment: front intraoral view Summer 2019 PCSO Bulletin Figure 4. Cut support arms and add an elastic chain or NiTi springs to begin intrusion mechanics 55