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A Literature Review of t Extraction Decision and Outcomes in Orthodontic Treatment
Objectives:
To provide an organized resource for clinicians and patients to use to understand the treatment options and outcomes for orthodontics in terms of extracting or not extracting permanent teeth.
Methods:
Literature published from January 2000 to current was searched in the electronic databases Cochrane Central Register of Controlled Trials and PubMed. Study inclusion criteria included comparing the extraction technique versus no extraction, average age of participants was 10 years old, and if relevant, crowding between 4-10 mm. Each article was arranged by type of extraction and malocclusion corrected to find similarities. The data was observed for common variables measured.
Results:
From the 23 articles reviewed, 10 appear to fit the criteria. Although some studies showed contradicting results, there can be some associations drawn. A trend can be noted of an increase in the incisor mandibular plane angle (IMPA), an increase in lower lip thickness, and proclination of incisors after orthodontic treatment with no extractions. In extraction cases, findings were almost the opposite, as lips are more retruded and incisors are more retracted. These findings, along with the other variables, provide an insight as to what facial profiles would be best suited for which treatment.
Conclusions:
Patients with more proclined incisors and more protrusive lips may be better with an extraction treatment plan to help compensate for these traits. Ultimately, to decide the best treatment, each case should be assessed individually, as other factors, such as crowding, age, and malocclusion, can lead to vastly different results.
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