Long-term stability of open bite treatments

peer reviewedThe long-term stability of open bite treatments is very difficult to obtain due to several parameters (genetic, myofunctional or/and parafunctional diseases). Methods :17 adult patients suffering from basal open bite were treated by a combined orthodontic treatment and orthognathic surgery. The surgery protocol was always a Lefort I osteotomy, except in case of class II, where a sagittal mandibular osteotomy was also performed in the same operation. Five parameters were taken into account to assess the long term stability of the treatment : Angle class, occlusal plane rotation, type and duration of retention after orthodontic treatment, tongue position and overbite. Results : we had a minimum 2-years observation after a combined orthodontic/orthognathic surgery treatment to evaluate the long-term stability of this type of treatment. Cephalometric parameters (Angle class, occlusal plane rotation, tongue position and overbite) measured at T2 and T3 showed a good long term stability after 2 years (T3). Conclusions : The posterior maxillar impaction must be more important than the anterior maxillar impaction to be the key to a long-term stability in open bite treatments. The tongue position is also a relevant element to maintain the right dental occlusion. A minimum one year combined with bimaxillar retention is also required to obtain a good and stable result of treatment