Balancing the extraction of primary teeth: a review

Balancing the extraction of primary teeth is a procedure advocated to maintain symmetry of the developing dentition by encouraging symmetrical drift of teeth mesial and distal to the extraction sites on each side of the dental arch. Current opinion about this procedure expressed in standard reference works is confused and occasionally contradictory. Whilst some authorities cite specific situations where balancing extractions should be performed, others are less precise with their advice, and at least one considers that there is little justification for the procedure. Scientific evidence supporting the procedure is tenuous. The one study carried out specifically to compare dental centre line shift following unilateral or bilateral extraction of primary teeth showed greater shift in cases of unilateral (unbalanced) extractions. Other studies do not directly address the issue and such information as they offer is imprecise. Although the procedure of balancing extractions is strongly advocated by many clinicians, it is not based on definitive experimental evidence.