Published: 2022-02-21

Treatment of a class II malocclusion patient with twin block appliance: a case report

Nilanjana Sarkar, Sumitra Reddy, Sumit Goel


Class II malocclusions in growing patients is commonly encountered and respond well to functional appliances, provided the clinical and cephalometric findings are favourable. In case of class II hypodivergent malocclusion, the hypodivergent pattern is established early and become prominent with progression of time. These patients have significantly smaller mandibular plane angles and smaller gonial angles. This case report describes the treatment planning of a patient of age 14 years with class II malocclusion showing hypodivergent growth pattern and moderate crowding. Treatment was started with twin block functional appliance and non-extraction approach was planned. As the patient was in his peak growth spurt stage, the functional appliance therapy use at this stage was started to take advantage of that. Fixed orthodontic appliances were placed after completion of functional appliance therapy. The treatment resulted in achievement of class I molar relation bilaterally, normal overjet and overbite and favourable soft tissue profile, facial balance and harmony.


Class II malocclusion, Hypodivergent growth pattern, Functional appliance

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