is in agreement with Baccetti et al (1998 ) 2 but they used a combination of a bonded maxillary expander and face mask therapy and again they concluded that this combination is more effective in early mixed dentition than in late mixed dentition with regard to the magnitude of the protraction effects on the maxillary structure. No side effects with using chin cup was observed in this study in contrast to the study of Gallagher et al (1998) 20 who found that the mandible was rotated down ward and back ward while the incisors were up righted. This effect on the mandible was attributed to a significant chin cup effect exerted by the face mask. The appliance was inserted from the palatal and lingual side so as to not be visible to others whereas the face mask may lead to some social problems because of the social impact on children that can occur due to their dentofacial appearance. This is in agreement with Fonte et al(2008). 21 tional intensive research to investigate its effect and the possibility of the replacement of face mask treatment. Recommendations The following modifications may be needed from our point of view and after our clinical experience for better manipulation and ease of use of the appliance. ᕡ A compression clamp in each side that allows the titanium coil inside the tube to be fully compressed to allow easy insertion and fitting in the mouth. The clamps will be released after fitting the appliance in the mouth and complete setting of the band cement. ᕢ The force delivered from the incorporated tita-nium coil spring must be measured by the manu-facturer and printed on the appliance itself . ᕣ A wide range of forces must be available to fit the needs of the individual cases. The anterior part of the appliance needs to be modified from round wire to a flat segment that is curved somewhat palatally to allow a wider area of contact thus affecting the forward growth of the anterior part of the maxilla. Conclusions The upper sagittal arch developer produced a pure dental effect on upper incisors. Thus changing their axial position relative to the FH plane , NA plane and N Pg line thus correcting the anterior cross bite effectively. At the same time this solves the big problem of patient coopera-tion in young children during orthodontic treatment. The combination of an upper sagittal arch developer combined with chin cup therapy is an idea of interest and needs addi-Editor’s Note: Article references are available upon request or for download in the digital version at www.orthodontics.com. 22 November/December 2011 JAOS
Journal of the American Orthodontic Society November-December 2011: Page 22
