Objectives: To investigate the reliability of mechanical and adhesive methods of fixing rectangular wires in the cross-slot of a mini-implant. Materials and Methods: A twin-hooked wire element was placed and fixed in the slot of a mini-implant via a NiTi spring under tension, or by means of an adhesive. For the purpose of mechanical anchorage, the wire was crimped with a special crimping tool to increase its thickness and prevent it from slipping through the slot. Before applying the adhesive, there were four possible methods of preparation: Untreated Wire (Adh. 1); ROCATEC-Pre (Adh. 2); ROCATEC-PRE + Espe Sil (Adh. 3); ROCATEC-PRE + ROCATEC-PLUS + Espe Sil (Adh. 4). The mechanical fixing and two adhesive fixings were aged by means of temperature change (500 cycles). A Zwick universal testing machine was used to measure the maximum strength of the coupling. Results: In all tests, the untreated wire + adhesive withstood the lowest maximum load (Ø 3 N and 10.8 N respectively) and failed the aging test after a maximum of eight cycles. The wires in test group Adh. 4 withstood the highest maximum load (Ø 43.3 N; 41.5 N; 45.9 N after aging) in all tests. The average load withstood by the crimped ligature was 38.7 N. Conclusion: The adhesive method of fixation performs best when the rectangular wire is sand blasted and silanized before application. The mechanical coupling using the crimped ligature is reliable.

Background: A review of literature indicates the Arab cephalometric pattern compared to the Caucasian cephalometric pattern is skeletally bimaxillary retrusive, dentally bimaxillary protrusive, and more divergent palatal and mandibular planes. Objective: The aim of this study was to clarify the cephalometric features of Emirates adults with Class I malocclusion and pleasing soft tissue profile and to evaluate for gender differences. The null hypothesis tested was no differences in lateral cephalometric measurements as a function of gender. Materials and Methods: The lateral cephalometric radiographs of adult Emirati nationals with Class I malocclusion were analyzed in order to characterize an indigenous Class I malocclusion population in the United Arab Emirates. Lateral cephalometric radiographs of 30 males with average age of 24.52±6.09 years and 31 females averaging 23.57±5.52 years were analyzed using Dolphin Imaging software. Twenty-two hard and soft tissue measurements comprised the cephalometric analysis. Results: Only one gender difference was demonstrated out of the 22 cephalometric analysis measurements used in the study; SN-PP mean for females (10.74±3.44 degrees) subjects averaged a 2.3 degree higher mean value than the males (8.43±3.95 degrees, P=0.018). The cephalometric study results were compared to published norms from Steiner and Eastman. Conclusions: Based upon the conditions of the present study, it may be concluded that adult Emirati males and females seeking orthodontic treatment with Class I malocclusion present similar cephalometric profiles with the exception that measurement SN-PP may be steeper in females than males. Moreover, Emiratis are likely to present greater incisor proclination and protrusion than Caucasians and may be generally considered as more bimaxillary protrusive.