Fouzi Boukhazani (1), Abdelhak Bennara (1), Nelson Oppermann (2), Fatma Si Ahmed (3) (1) Assistant lecturer, Department of Orthodontics & Dento-Facial Orthopedics, Mustapha Pacha University Hospital, Algiers, Algeria. (2) Visiting Professor, Department of Orthodontics, University of Illinois at Chicago, Chicago, USA. (3) Professor, Department of Orthodontics & Dento-Facial Orthopedics, Mustapha Pacha University Hospital, Algiers, Algeria. Abstract Various appliances have been proposed for the interception of Class II division 1 malocclusions. In this context, orthodontic trainers are claimed to unlock mandibular growth and to correct functional associated disorders. In this case report of 10-year-old girl diagnosed as Class II division 1 malocclusion, an interceptive approach was decided using an orthodontic trainer with the mandible in protruded position. At the end of this interceptive treatment, treatment changes have been evaluated with lateral cephalograms superimposition between T0, T1 and T2. After 12 months application, the orthodontic trainer has shown a good dento-skeletal results but It required a good patient and parents compliance. We concluded that the orthodontic trainers can be very useful for interceptive procedures if a proper case and appliance selection are made and a good patient compliance is obtained. Key words: interception, class II division 1 malocclusion, trainers, unlock, compliance. I. Introduction The most frequent skeletal problem in class II division 1 malocclusions, in growing patients, is mandibular retrognathia associated to functional disorders. Several interceptions techniques and appliances have been proposed to eliminate functional, mechanical and psychological interferences with mandibular growth. In this context, orthodontic trainers are used to unlock mandibular growth and to correct functional associated disorders. The aim of this case report is to evaluate the skeletal and dento-alveolar effect of the orthodontic trainer in 10 year-old girl diagnosed as class II division 1 malocclusion associated to functional disorders. These treatments effects were evaluated with superimposition of T0, T1 and T2 Cephalograms. II. Case description Fig 1: Pre-treatment photos Figure 3: Treatment results S E S E After treatment T1 Pre-treatment T0 Figure 2: Pre-treatment X rays The appliance choice: Orthodontic trainers (Figure 5) are functional appliances which become active through muscular forces and bring dentoalveolar and skeletal changes. They can be used to obtain expansion by the correction of the tongue posture. Some types are used to treat mandibular retrognathia because they are constructed in protruded position of the mandible (Activator). 3 7 1 5 4 6 2 1:Lip bumper 2:Tongue elevator 3:Eruption guide 4:Protrusion correction 5:Deep bite correction 6:Mandible propulsion 6 months laterT2 Figure 4: Post treatment X rays ) III. Discussion The application of the orthodontic trainer induced a good dento-skeletal results after 12 months comparing to the objectives visualized (VTO) before the treatment (Figure 7). The same results were obtained in the study of DAS and REDDY in India after 15 months and in the study of USUMEZ and coll in Turkey after 13 months however these results required the patient sand the parents compliance even in our case. At the end of the interception, the corpus axis improved from 54mm to 62mm which can be explained by the mandibular growth forward. The occlusal plan was successfully reoriented as shown in the superimpositions. This reorientation is a guarantee for the treatment results long term stability. 7:Indirect maxillary expansion Figure 5: Orthodontic trainer effects In our case, we had to cut the trainer posteriorly in order to allow the upper molars extrusion to help the deep bite correction and to reorient the occlusion plan (Figure 6) T0 T1 Figure 7: The used trainer Figure 7: VTO and superimpositions T0= before the interception T1= end of the interception T2 = 6 months after the end of the interception T2 IV. Conclusion The orthodontic trainer with a compliant patient induced an interesting treatment results after 12 months application. It can be a real alternative to other techniques and appliances for the correction of the class II division 1 malocclusions in growing patients specially in low income countries. References 1. Chen JY, Leslie AW, Niederman R. Analysis of efficacy of functional appliances on mandibular growth. Am J Orthod Dentofacial Orthop 2002;122:470-6. 2. Das U M, Reddy D. Treatment effects produced by preorthodontic trainer appliance in patients with class II division I malocclusion. J Indian Soc Pedod Prev Dent 2010;28:30-3. 3. Mc Namara JA. Components of Class II malocclusion in children 810 years of age. Angle Orthodontist 1981;51:177-202. 4. Tallgren, A. , R. Christiansen , M. M. Ash , and R. L. Miller . Effects of a myofunctional appliance on orofacial muscle activity and structures. Angle Orthod 1998. 3:249–258. 5. Usumez S, Uysal T, Sari Z, Basciftci FA, Karaman AI, Guray E. The effects of early Preorthodontic trainer treatment on class II division I patients. Angle Orthodontist 2004;74:605-9.