RECENT!TRENDS!TOWARD!NON=EXTRACTION!!Extraction! rates! always! have! varied! among!doctors! and! regions,! so! no!specific!example!of!changes!in!extraction!patterns!can!be!taken!totally!as!typical.!!At!its!inception!in!the!1950s,!treatment!in!the!clinic!was!strongly!influenced! by! the! attitudes! like! Angle’s.! By! the! 1960s! the! Tweed/Begg!view! had! been! accepted,! and! extraction! rates! increased! dramatically.!From! then! until! the! early! 1990s! there! was! a! continuing! decline! in!extraction!rates,!which!has!stabilized!or!increased!slightly!recently.!
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