A new non-surgical approach for treatment of extreme dolichocephalic malocclusions. Part 1. Appliance design and mechanotherapy.

of maxillary molar extrusion in vertical facial development.1,2 Other reports followed,3-5 along with a cephalometric analysis centered around vertical diagnosis.6 Subsequent studies identified treatment modalities that could be used to control and, to a limited extent, reduce the vertical dimension during conventional orthodontic treatment. No investigator has published in this field as long as Pearson,7,8 who has employed mandibular cervical traction,5 a vertical-pull chin cup,9 and vertical-pull headgear.10 Others have used posterior bite blocks of varying thicknesses,11 as well as spring-loaded appliances12,13 and repulsive magnets.13-17 Kuhn18 and Thurow19 proposed a high-pull headgear in conjunction with maxillary dental occlusal coverage, while DeBerardinis and colleagues used a transpalatal acrylic pad, constructed at some distance from the hard palate, to transmit an intrusive force from the tongue to the maxillary molars.20 Villalobos and colleagues were able to prevent some eruption of mandibular molars with a lingual holding arch.21 The influence of soft tissue on the dolichofacial patient has also been investigated. Measurable results were obtained in young children who chewed a tough resin,22 and this prompted additional study.23,24 More recently, the reports of English and colleagues served as a reminder of the importance of muscle activity in the dolichocephalic face.25-27 During orthodontic treatment of these patients, an increase in the vertical dimension is generally accompanied by unfavorable changes in facial esthetics. Conventional functional appliances tend to increase anterior facial height (AFH) by encouraging mandibular molar eruption28-32; the present author developed a functional appliance that controlled AFH, but could not reduce it.33 Class II elastics are likewise contraindicated in Class II patients with vertical excess, because they exert an extrusive force on the mandibular molars and maxillary incisors. Interarch compressive springs can be used in dolichocephalic facial patterns,34 but still have produced no reduction in AFH.35 With the advent of skeletal anchorage, vertical control became a more realistic treatment goal. The pioneering report of Creekmore and Eklund described a case of maxillary incisor intrusion.36 The onplant of Block and Hoffman37 was then introduced, followed by the mini-implants of Kanomi, who demonstrated both anterior and posterior dental intrusion.38 A few years later, Umemori and colleagues, using skeletal anchors, reported pronounced mandibular molar intrusion and subsequent open-bite correction.39 This technique was recently described in more detail,40 and a similar approach by Sherwood and colleagues intruded the maxillary molars in four adult patients with anterior open bites.41 Comparable results have been obtained using miniscrews.42 In all the reports listed above, only minor to moderate reductions in AFH and mandibular plane angle (MPA) were obtained, and these were lim-