[Role of the lip-bumper in nonextraction orthodontic therapy: clinical-statistical study]

The purpose of this study is to investigate the morphologic and dimensional changes of lower arch that might occur in patients undergoing treatment with the lip-bumper. After a brief examination of the clinical applications of lip-bumper, we report the results of a research concerning 20 children in the mixed dentition period. The effect of this simple orthodontic appliance has been an expansion of the mandibular dental arch, with a real increase of arch length and transverse dimension. Therefore the lip-bumper can be used in non-extraction treatment of malocclusion, in order to obtain a space recovery in lower arch.