THE DECISION TO EXTRACT .2. ANALYSIS OF CLINICIAN STATED REASONS FOR EXTRACTION

In a recently reported study, the pretreatment records of each subject in a randomized clinical trial of 148 patients with Class I and Class II malocclusions presenting for orthodontic treatment were evaluated independently by five experienced clinicians (drawn from a panel of 14 ). The clinicians displayed a higher incidence of agreement with each other than had been expected with respect to the decision as to whethe r extraction was indicated in each specific case. To improve our under standing of how clinicians made their decisions on whether to extract or not, the records of a subset of 72 subjects randomly selected from the full sample of 148, have now been examined in greater detail. In 2 1 of these cases, all five clinicians decided to treat without extract ion. Among the remaining 51 cases, there were 202 decisions to extract (31 unanimous decision cases and 20 split decision cases). The clinic ians cited a total of 469 reasons to support these decisions. Crowding was cited as the first reason in 49% of decisions to extract, followe d by incisor protrusion (14%), need for profile correction (8%), Class II severity (5%), and achievement of a stable result (5%). When all t he reasons for extraction in each clinician's decision were considered as a group, crowding was cited in 73% of decisions, incisor protrusio n in 35%, need for profile correction in 27%, Class II severity in 15% and posttreatment stability in 9%. Tooth size anomalies, midline devi ations, reduced growth potential, severity of overjet, maintenance of existing profile, desire to close the bite, periodontal problems, and anticipation of poor cooperation accounted collectively for 12% of the first reasons and were mentioned in 54% of the decisions, implying th at these considerations play a consequential, if secondary, role in th e decision-making process. All other reasons taken together were menti oned in fewer than 20% of cases. In this sample at least, clinicians f ocused heavily on appearance-related factors that are qualitatively de terminable by physical examination of the surface structures of the fa ce and teeth. They appear to have made primary use of indicators avail able on study casts and facial photographs and relatively little use o f information that is available only on cephalograms or that involves the application of specialized orthodontic theories.