Mandibular Advancement Device

A mandibular advancement device produces statistically significant reduction in apnea events. The Twin-Block appliance increased the mandibular plane angle by 1.0° and anterior facial height by 1.2 mm compared with controls. Dental devices outperform positional therapy but are slightly inferior to CPAP. The Herbst appliance produces similar unfavourable clockwise rotation to the Twin-Block, making both appliances suboptimal for long-face cases. Mandibular advancement devices demonstrate substantially greater effectiveness than physical activity. A mandibular advancement device is a dental appliance that repositions the lower jaw forward. In hyperdivergent patients, the pre-existing occlusal plane inclination causes the mandible to rotate clockwise on forward movement with mandibular advancement devices, elongating posterior teeth and worsening the facial profile. Mandibular advancement devices such as the Activator, Herbst, and Twin-Block are well-indicated for patients with mandibular retrognathia and adequate growth potential at CVM stages CS3–CS4 in low-angle or normodivergent patterns.