Abstract
Purpose: There has been no systematic clinical study of the scientific evidence of replacing missing teeth. We suggest that the number of teeth being replaced should not only be decided from morphologic and dynamic viewpoints, but also from a diverse viewpoint.
Study Selection: To prove the suggestion, a series of research of Kayser (Netherlands) advocating the Shortened Dental Arch (SDA) Concept is reviewed.
Results: Kayser et al. reported that there were no significant clinical differences between a SDA of 3-5 occlusal units (one molar unit is considered to be equivalent to two occlusal units) and a complete dental arch in the migration of teeth, masticatory ability, TMD, periodontal support, and oral comfort. Therefore, it was proposed that the anterior and premolar regions should always get the best quality care throughout life. In long-term longitudinal clinical studies, the SDA group indicated minor changes of the criteria on occlusal stability, however, the occlusal relationship remained stable in the evaluation period. As a result, the studies suggested that the changes were adaptation leading to a new equilibrium and SDA did not result in occlusal collapse.
Conclusions: From this review of literature, it was revealed that the SDA Concept might be a dental therapy validated by the scientific evidence. Consequently, a strategy to reduce complex restorative treatment in the molar area may be accepted.
