Myth and evidence in palatal expansion

Untruths and distortion of scientific findings inhabit the medical and dental fields, not intentionally but often because of the lack of firm evidence. The aim in this paper is to visit a common orthodontic treatment modality, palatal expansion, and explore whether the accumulated biologic and mechanical findings are sufficient or misinterpreted for proper intervention. Specifically, questions are raised regarding the sutural response to maxillary widening in relation to the age-related changes in the morphology of the suture. The fractures occurring when expansion is performed of a heavily interdigitated suture and the healing that leads to closure that, depending on the timing may impede the sutural pubertal growth spurt. Later widening of the arch width, even when surgically assisted, may lead to a bony relapse and severe bony dehiscence of the lateral teeth. Extensive research is needed to help generate appropriate guidelines for palatal expansion especially the age of the patient, timing and amount of expansion duration of retention and factors of importance for maintenance of the treatment results.