Class III treatment by combining facemask (FM) and maxillary skeletal expander (MSE)

Abstract

Class III malocclusion can be treated dentally as well as skeletally depending on the nature of the problems and the skeletal maturity of the patients. When young patients present skeletal discrepancy, use of a facemask (FM), with or without palatal expansion, is one of the traditional approaches. This treatment modality involves utilization of maxillary dentition as an anchorage unit, often resulting in excessive flaring of the upper incisors by forward movement of maxillary dentition, and an increase in the vertical dimension of the lower face by buccal tipping and extrusion of maxillary posterior dentition, especially in high-angle cases. In recent years, incorporating micro-implants (MI) with expansion and protraction devices in various ways, in order to avoid the unwanted dental side effects, resulted in significantly better outcomes. One popular application is the use of a micro-implant-assisted rapid palatal expander (MARPE), by incorporating the MI with an expansion device, in order to promote bone anchored expansion, and by applying FM force against MARPE, in order to promote bone anchored protraction. Among countless designs of MARPE, the Maxillary Skeletal Expander (MSE) has unique features that produce unique treatment results. MSE causes expansion of the entire midface, disrupting all perimaxillary structures. When MSE is applied in combination with FM, almost negligible vertical side effects are observed, the existing antero-posterior dental compensation can be reversed, the maxilla advances efficiently in large magnitude, and the skeletal protraction is possible even in older growing patients. Combining FM and MSE has also resulted in some skeletal protraction even in mature patients, simulating distraction-like movement, which gives hope of discovering a novel non-surgical orthopedic treatment modality for Class III adult patients.