Richard A Alexander

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OBJECTIVE To evaluate differences in long-term postretention changes between adolescents and adults. MATERIALS AND METHODS The sample included 96 subjects, 51 adolescents and 45 adults (14.2 +/- 0.8 and 21.5 +/- 6.8 years of age, respectively, at the end of treatment) retained for 3 years and followed approximately 16 years post treatment, who were(More)
OBJECTIVE To develop models for predicting changes in lip position of Class I extraction patients. MATERIALS AND METHODS Pretreatment and posttreatment lateral cephalograms of 46 white female adults and 109 white female adolescents were examined. Mean pretreatment ages for the adolescent and adult groups were 12.2 +/- 1.2 years and 23.0 +/- 8.5 years,(More)
OBJECTIVE This retrospective study was designed to evaluate the morphologic effects of masticatory muscle exercise as an adjunctive therapy for hyperdivergent patients treated with fixed orthodontic appliances. MATERIALS AND METHODS Three samples of 50 subjects were selected, including one sample treated with orthodontics combined with exercise, one(More)
The mean CO2 concentration on the Space Shuttle is 0.3% and has reached 0.7%, for extended periods of time. Following space flight, it has been shown that both humans and animals have significant changes in red blood cell counts (RBC) and white blood cell counts (WBC). In other studies, where no difference occurred in total WBC, a significant change did(More)
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