Extraction of premolars for orthodontic reasons on the decline? A cross-sectional survey of BOS members

Objective: To obtain the opinion of British Orthodontic Society (BOS) members in relation to possible patterns of prescription of orthodontic extractions over the past 5-10 years and to relate any changes identified to treatment objectives, facial and smile aesthetics, and treatment strategies and adjuncts. Design: Cross-sectional questionnaire. Setting: On-line survey of BOS members. Methods: A 14-item on-line questionnaire was sent to orthodontic practitioners for completion. The questionnaire covered demographics, possible changes in frequency of prescribed extractions with specific information concerning the effect of patient age, and the influence of other factors including alternative approaches to space creation, evolving treatment mechanics, smile and facial aesthetics, and retention protocols. Results: Two hundred and eight responses were obtained with 95.6% (n = 199) reporting reduced extraction prescription over the last 5-10 years. Overall, 29.9% and 35.5% felt that their threshold for extractions had increased by more than 2 mm in adolescents and adults, respectively. Facial (n = 145; 69.7%) and smile (n = 127; 61.1%) aesthetics, and increased use of inter-proximal reduction (n = 102; 49%) were the factors most frequently reported as having either a moderate or major influence on this trend. Based on ordinal logistical regression analyses, no significant relationship was found between threshold for extractions and work setting (P = 0.675; O.R. 0.51; 95% CI: 0.39, 1.85) or level of orthodontic experience (P= 0.15; O.R. 1.02; 95% CI: 0.15, 1.05), although a higher threshold for extractions was more likely among users of conventional than self-ligating brackets (P= 0.001; O.R. 4.74; 95% CI: 1.95, 11.5). Conclusions: A reduced tendency to prescribe orthodontic extractions over the past 5-10 years among British Orthodontic Society members was identified. Comparative clinical research exploring the relative merits of extraction and non-extraction approaches could be timely.