Background. This article examines some of the data-driven advances in clinical orthodontics and how they might influence the decision-making process in the specialty.
Types of Studies Reviewed. Nearly 100 years of orthodontic study has focused on two issues: one-phase versus two-phase treatment of Class II malocclusion and extraction versus nonextraction treatment of arch perimeter deficiencies. The author addresses these issues by presenting data from the first randomized clinical trial in orthodontics and from a survey of the current literature.
Results. The clinical trial involved subjects who had Class II malocclusion. The researchers who conducted the trial found no difference in the quality of the dental occlusion between the children who had early treatment and those who did not, as judged by both an occlusal index (Peer Assessment Rating scores) and the percentages of the subjects with excellent and less-than-optimal outcomes. Early treatment did not reduce the eventual need for orthognathic surgery. In a separate study, a researcher reported that the maxillary arch perimeter could be increased by 3 to 4 millimeters by using rapid palatal expansion, or RPE, providing space for incisor alignment to resolve crowding. The author concluded that any added benefit of RPE treatment in patients without a crossbite might be "challenging to define."
Clinical Implications. The challenge facing orthodontists in the 21st century is the need to integrate the accrued scientific evidence into clinical orthodontic practice.
