Headgear-activator And Self-ligating Brackets Combination In The Treatment Of Skeletal Class Ⅱ Malocclusion

Objective: To evaluate the efficacy of headgear-activator and self-ligatingbrackets combination of dual-phase continuous treatment on pubertal peak of skeletalClass II malocclusion.Methods: A male patient with skeletal Class Ⅱmalocclusion was selected fromShenyang Stomatological Hospital in July2009,who was12yeas old2months. Normalmaxilla and mandibular retrusion relative to the maxilla;the bilateral molar distal tip ofthe tip of the relationship;deep overbite of incisor III degree and overjet III degree. Thepatient is in the peak period of growth and development,who is treated by the dual-phase continuous and non-extraction treatment. In the first stage treatment,headgear-activator was adopted because this may promote the development of mandible,controlsthe maxillary growth and improves the soft tissue profile appearance in the mean time.In the second stage treatment,self-ligating brackets technology was used because it caneffectively expand the dental arch width and shorten alignment time. Collectmodel,shooting face,mouth graph,panoramic radiographs,lateral cephalograms in orderto observe the teeth,root development situation, and measure changes in the hard tissueand soft tissue. The cephalometric measurement was made to analyse the outcome.Results: The treatment takes25months. Self-ligating brackets orthodontictechnique relatively shortens the treatment time. After dual-phase continuoustreatment,patients teeth are alignment;anterior teeth overbite and overjet weresolved;bilateral molars and canines are back to neutral relationship;all the teethachieved good occlusion. There is no significant increase in the full-arch length after thedual-phase continuous treatment. However,the anterior and middle of the arch widthincreased significantly,the posterior dental width was not obviously increased.Cephalometric comparative data analysis before and after the treatment:(1) Maxillary is almost unchanged,the mandible have significant change in the sagittal and vertical.SNA increased by0.5°,SNB increased by3.2°,ANB decreased2.7°,mandibular planeangle (MP-FH) decreased1.8°.(2) Deep facial have growth,but the most significantgrowth is the length of the mandible.(3) Facial height also growth, there has a bettercoordination.(4) Upright inclination of upper incisor，Labial inclination of lower incisor.The U1-SN angle decreased from116.3°to106.5°,and increased to107.8°at the end ofthe second phase,the Ll-MP angle inereased from92.2°to99.3°.(5) Nasolabial angle ofsoft tissue (NLA),surface angle (FCA),upper lip protrusion(ULP)was decreased;Lowerlip protrusion(LLP) increased significantly. Measurement data of each numerical tendsto be normal. Soft tissue retrusion were changed largely after treatment. The patient andhis parents were satisfied with the results of treatment.Conclusion: Application of headgear-activator and self-ligating bracketscombination of dual-phase continuous treatment on pubertal peak of skeletal Class IImalocclusion is worthy of recognition. Headgear-activator can improve skeletal Class IIbone relationship,soft tissue profile obtained satisfactory therapeutic effect. Self-ligatingbrackets appliance has soft and comfortable forces which can relieve pain, andeffectively reduce the patients visit time. It is an effective method for functionalappliance orthodontic treatment with fixed appliance.