Accelerated Invisalign treatment of patients with a skeletal Class III

In skeletal Class III patients, severe disharmony of the maxilla and mandible is corrected surgically. However, there is a wide variety of criteria for this surgery and practitioners must often select a non-surgical treatment if requested by the patient. In such a situation, in patients where anterior crowding is accompanied by anterior crossbite, a common treatment involves improvement through mandibular pre-molar extraction and lingual inclination of the mandibular incisors1. In addition, expansion of the maxillary dental arch is an effective technique. However, from an aesthetic point of view, patients occasionally choose a multi-bracket appliance, even on the lingual side, in favour of a removable device. Just a few years ago, when compared with multi- bracket treatments, aligners usually required longer treatment times and the lack of precise control of axial movement led some to suggest that cases treated with aligners must be chosen carefully2. Since 2010, when Schupp et al presented a successful treatment of class II relationship using the Invisalign system with non-extraction, but molar distalization3, more and more practices have begun to treat patients previously believed to need extraction with a non-extraction distalization approach4- 6. Compared with case reports on the distalization of maxillary molars, the number of mandibular-molar distalization case reports is lower7, and clear data (molar distalization distance limits) have not yet been presented. This article reports two patient examples. In the first, we used the Invisalign technique only, changing the aligners every 7 days. The second patient example shows a non-surgical treatment of a severe skeletal Class III using a combination of aligners with temporary anchorage advices (TADs)8 and AcceleDent9-11 (OrthoAccel Technologies, Inc, 6575 West Loop South, USA)] obtaining more effective and faster mandibular molar distalization. Keywords: accelerated aligner treatment, aligner treatment, Class III treatment, distalization in the mandibular arch, Invisalign, skeletal anchorage