First Generation Evidence-Based Extraction Case Result By Leonard J. Carapezza, DMD Angle, who invented the Edge-wise orthodontic bracket, empha-sized and taught non-extraction orthodontic treatment—arch expan-sion and wire bending for place-ment of first order (in-out), second order (angulation), and third order (torque) beds. Wire bending was a Andrews SWA: E dward H. Angle became known as the father of modern-day orthodontics at the beginning of the 20th century. By the beginning of the 21st century, Lawrence F. Andrews became known as the father of space-age orthodontics. I. 1. 2. 3. 4. 5. 6. Class I Classic (Ideal Lower Arch) Class I Non-extraction (0-6 mm crowding) Class I A-7 mm crowding Class I B-10 mm crowding Class I C-14 mm crowding Class I D-6 mm crowding * 3 Types—A, I3, C, D * e.g. Class IA, —Means lower incisal ideal—Crowding only Class IA, —Means no crowding—lower too far forward Class IA, —Means 1/2 crowding V2 incisors too far forward II. 1. 2. 3. 4. 5. 6. Class Class Class Class Class Class II II II II II If Classic (Ideal Lower Arch) Non-extraction (0.6 mm crowding) A-7 mm crowding + Class II B-10 crowding + Class II C-I4 mm crowding + Class II D-6 mm crowding + Class II III. 1. 2. 3. 4. 5. 6. Class Class Class Class Class Class III III III III III III Classic (Ideal Lower Arch) Non-extraction (0-6 mm crowding) A-7 mm crowding + Class III 13-10 crowding-+ Class III C-I4 crowding + Class III D-6 crowding + Class III Fig. 1 major function of the orthodontist’s clinical skills and a dominant requirement of the orthodontic specialty training program. In the 1940s and 1950s, the Edgewise approach to orthodontic treatment was shown to be unsta-ble and fostered the popularity of the 4-Bicuspid Tweed extraction orthodontic practice. In the mid-20th century, the Begg Extraction Technique became prevalent. In the 1960s and 1970s, Andrews established a Clinical Orthodontic Research Foundation in conjunction with his private practice in San Diego, CA. Find-ings at the foundation included the Six Keys to Normal (Optimal) Occlusion 1 and Revolutionary Straight-Wire Fully Programmed Orthodontic Appliance. 2 The Andrews SW Rx bracket for each tooth type eliminated the need for first, second and third order arch-wire bending, simplifying orthodontic treatment. 3 A concern about extraction ther-apy negatively affecting facial esthetics and leading to TMJ dysfunction brought into the United States the post-war Euro-pean use of functional removable appliances. 4 The 1980s gave rise to evidence-based clinical practice via randomized clinical trials (RCTs). 5 Multiple orthodontic systems became popular, including Biopro-gressive Early Treatment Utility 24 Spring 2026 JAOS
Journal of the American Orthodontic Society Spring 2026: Page 24
