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According to the claims of the manufacturer, aethylcyanoacrylate can be used to bond orthodontic brackets and some orthodontists have already adopted its use for this purpose. Because, however, the use of the material as thus applied has not yet been the object of research, the question of its adhesion to tensile forces immediately after bonding and after 50, 100, and 150 days of placement in a physiologic saline solution (0.9% NaCl) is the subject of this study. 40 bovine upper incisors were extracted from 20 animals for each of the four points in time. The brackets were bonded with Cyano-Veneer and Mono-Lok according to a randomized list. Mono-Lok, an adhesive from the group of common orthodontic adhesives, functioned as the reference material. The bonding strength of the brackets in relation to the tensile forces was measured by means of a "Zwickuniversalprüfmaschine" (Zwick universal testing machine). Immediately after bonding, the cyanoacrylate demonstrated significantly higher bonding strength values than Mono-Lok. At 50, 100, and 150 days in the physiologic saline solution, the bonding strength of both materials showed no significant difference. It can thus be concluded that, when wires are employed immediately after bonding, the danger of bracket loss is significantly reduced through the use of cyanoacrylate.

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Maxillary alveolar arch morphology and growth was studied in 15 children with complete unilateral cleft lip and palate treated with passive orthopaedic plates. Nine patients were treated to the "Zurich concept" and compared to six children who had lip surgery and primary bone-grafting at about six months of age and complete palate closure at 18 months. Maxillary alveolar arch morphology was described at birth, at six months, at 18 months and at 4.5 years. After early orthopaedic treatment the alveolar and palatal cleft width decreased significantly, the major segment was relocated into a more normal position and the midline deviation was reduced, whereas the minor segment rotated towards the palate.