Treatment of Class II Malocclusion in the Growing Patient: Early or Late?

Abstract

The aim of this paper is to evaluate several factors that can improve the efficacy of Class II treatment in the growing patient with mandibular skeletal retrusion. Previous research has shown that functional appliances are most effective in altering short-and long-term mandibular growth and mandibular sagittal position if active treatment includes the pubertal growth spurt. If functional jaw orthopedic treatment is initiated in the prepubertal growth period, the positive occlusal changes are primarily dentoalveolar in nature. The staging of the maturation level of the cervical vertebrae (CVM method) has proven effective in differentiating the stages of maturation.The second factor, typically not considered routinely during the decision-making process, is the responsiveness of a specific patient to the prescribed treatment. Not all patients respond to the same treatment in the same manner. One way of predicting individual patient responsiveness is to evaluate mandibular morphology at puberty. Good responders to functional jaw orthopedics for Class II malocclusion with mandibular retrusion are characterized by a small mandibular angle (Co-Go-Me). Poor responders have larger mandibular angles.The third issue that is addressed is the question of whether an early phase of treatment is necessary in a Class II patient with mandibular skeletal retrusion. The most frequently seen deficiency in the early mixed dentition is narrowness of the maxilla. A measurement of transpalatal width between the closest points between the maxillary first permanent molars of 35-39 mm usually indicates that there is enough arch perimeter to accommodate teeth of normal size. If transpalatal width is constricted, an acrylic splint expander or a banded expander can be used to widen the maxilla. A removable lower Schwarz expander also can be used to gain a modest amount of lower arch perimeter while uprighting the lower posterior teeth. Rapid maxillary expansion in the early mixed dentition can help in improving Class II malocclusion as a side-effect, both skeletally and dentally.