After an orthodontic treatment the dentition would always be prone to relapse if the outcome wasn’t stabilized properly. The stabilization of orthodontic treatment outcomes is possible with the help of removable and fixed appliances.
For common plates, favourably used in Germany for retention, the prescribed wear-time is eight to sixteen hours a day. In a recent study scientists from the University of Tübingen could prove that patients’ compliance isn’t appropriate. One hundred patients were treated with orthodontic retainers into which microsensors were incorporated in order to estimate the daily wear-time. The collected data was read off by computers. The actual median wear-time was seven hours a day being far below the required level prescribed by the orthodontists. Moreover the scientists found out that the young patients showed a heterogeneous daily wear-time behavior. This is probably the reason why removable appliances often fail because during the first months after active treatment just a few days without optimal retention can be enough to force front teeth to relapse.
There’s of course the fixed retainer, a thin wire which is positioned on the backside of the front dentition without being seen – a reliable, economic and comfortable solution. Unfortunately retention with removable appliances is still of common use in Germany. The reason for this is of economic nature because German orthodontists earn double income with removables in comparison to fixed appliances – it’s obvious that this mistake resulting from the German system of reimbursement for dentists will not remain without consequences. Therefore it’s recommended to patients and parents to ask for fixed retainers just before the end of active treatment.
Reference:
Schott TC, Schlipf C, Glasl B, Schwarzer CL, Weber J, Ludwig B. Quantification of patient compliance with Hawley retainers and removable functional appliances during the retention phase. Am J Orthod Dentofacial Orthop. 2013 Oct;144(4):533-40. doi: 10.1016/j.ajodo.2013.04.020. PubMed PMID: 24075661