title: Long-term effect of rapid maxillary expansion studied in one patient with the aid of metallic implants and roentgen stereometry.
abstract: The articulatory displacement of maxillary bones during and after rapid maxillary expansion (RME) was studied with metallic implants and roentgen stereometry (RSA) for 3653 days in a girl aged 12 at start of treatment. She had a narrow upper dental arch with anterior crowding and a normal incisor relationship, and a normal sagittal molar relationship with bilateral cross-bite. Three implants were inserted in each maxillary bone and they remained stable in the bones during the 10-year observation period. In the 3-D analysis of the articulatory displacement, the left maxillary bone was studied in relation to the right bone in three periods: RME (23 days), retention (108 days) and follow-up (3522 days). Extensive relapse of rotations as well as translations was found and the long-term effect of RME was limited. In our opinion the relapse was caused mainly by the resistance to deformation from circum-maxillary sutures and surrounding soft tissue matrix, and inadequate bone formation in the involved sutures. As is generally known in clinical oral orthopaedics, changes obtained by short-term simple mechanical interference with a complex biological system tend to reverse spontaneously. Thus, the rationale for RME treatment may be seriously questioned.
authors: Centre for Craniofacial Anomalies, General Hospital, Malmö, Sweden.
authors: K V
authors: KV
authors: Sarnäs
authors: A
authors: A
authors: Björk
authors: B
authors: B
authors: Rune
mesh_terms: D001696:Biomechanical Phenomena; D002648:Child; D015921:Dental Implants; D003799:Dental Stress Analysis; D005260:Female; D006801:Humans; D008310:Malocclusion / Q000628:therapy; D008437:Maxilla / Q000000981:diagnostic imaging / Q000254:growth & development* / Q000503:physiopathology; D017063:Outcome Assessment, Health Care; D010155:Palatal Expansion Technique; D011859:Radiography; D012008:Recurrence; D012399:Rotation
chemical_list: D015921:Dental Implants