Research Article| Volume 28, ISSUE 3, P212-226, September 2022

Asymmetric dental-alveolar transversal corrections with skeletal anchorage

Published:October 27, 2022DOI:


      Transversal asymmetries of the dental arches are common orthodontic problems. Significant asymmetries needed a surgical approach for their correction before the introduction of skeletal anchorage. This paper presents two different approaches to correct dental transversal asymmetries, using skeletal anchorage both directly and indirectly. The direct use of skeletal anchorage requires careful planning of the desired dental movement and the estimation of the line of action of the needed force to achieve it. This information can be used to orientate the orthodontist in the screw placement, since it should be inserted, if possible, along the line of action of this force. In this way, it is possible to design appliances that do not deliver to the screw moments, which can compromise their stability. In the direct approach, the screw can be placed in the palatal vault or between the dental roots. The indirect use of skeletal anchorage implies the connection of the screw with one or some of the teeth which are required to maintain their position. Since the connecting wire should be rather short, it is recommendable to place the screw in the interradicular bone, rather than in the palate. This approach can be used with both fixed appliances, and with aligners. Four clinical cases illustrate these modalities of asymmetric expansion or contraction.
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