title: Analysis of clinical efficacy of interceptive treatment of Class II division 2 malocclusion in a pair of twins through the use of two modified removable appliances.
abstract: The interceptive therapeutic approach of a functional type is indicated for the treatment of Class II Division 2 mandibular retrusion with deep bite, where improvement is required not only in occlusal relationships but also in skeletal and aesthetic parameters.
  
  
  OBJECTIVE
  The aim of this study is to assess, in two identical twins suffering from the same malocclusion, the effectiveness and clinical stability of functional interceptive Class II division 2 treatment during puberty by mandibular retro-positioning associated with deep bite, and to compare skeletal changes and dental and dental-alveolar changes induced by the application of two different modified removable appliances: Clark's Twin block and Bergersen's Occlus-o-guide.
  
  
  RESULTS
  The results show that both devices allowed for circumvention of the pre-functional therapy phase aimed at correcting the upper labial segment, and for the conversion of the Class II division 1 incisor relationship, they were able to promote significant and obvious clinical effects.
  
  
  CONCLUSIONS
  The study shows that Class II Division 2 functional type interceptive treatment of mandibular retrusion with deep bite conducted in the puberal phase through clinical use of modified Bergersen's Occlus-o-guide(®) allowed for simultaneous resolution of the skeletal, dental-alveolar and dental problems in one step, while that using modified Clark's Twin-block still requires a second phase of treatment necessary to resolve the alignment, levelling, inter-cuspidation of the arches, optimization of the dental overjet and overbite parameters and to the stabilization of the basal Class I.
authors.affiliation: Department of Odontostomatologic Science, Paediatricc Dentistry University of Rome "Tor Vergata", Rome, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Condò
authors.forename: C
authors.initials: C
authors.lastname: Perugia
authors.forename: M
authors.initials: M
authors.lastname: Bartolino
authors.forename: R
authors.initials: R
authors.lastname: Docimo
keywords: Class II division 2; Twin Block; occlus-o guide®; paediatric patient