Abstract

Class II malocclusion in growing individuals presents with both skeletal and dento-alveolar malocclusion components that are frequently treated by functional appliance therapy. These appliances should aid in correction of skeletal deficiencies without compromising dental and soft tissue components by holding at its position to allow postural changes. Twin block is a simple bite block appliance with occlusal inclined plane that induces rapid functional correction of class II malocclusion with mandibular retrusion by transmitting favorable occlusal forces to the occlusal inclined planes covering the posterior teeth and guiding the mandible forward into defined occlusion. Various modifications have been in introduced over the period of time that facilitate simple activation, adjustment, tolerability, flexibility, adaptability, effectiveness and ease of incremental mandibular advancement without changing the appliance with independent control in vertical, sagittal as well as transverse directions. Several studies were carried out over the years to evaluate the skeletal, dental and soft tissue changes associated with twin-block functional appliance therapy nonetheless only few studies focusing on short-term treatment outcome and advantages were discussed in the past. The present review was aimed to briefly describe the clinical significance and potential short-term dental, skeletal, and soft tissue effects of treatment with Twin-block appliance. The study observed skeletal, dental and soft tissue changes associated with a Class II correction were of limited clinical significance. Nonetheless recent studies evaluated short-term effects of treatment performed with Twin-block appliance however long-term changes which benefits patients in all age group right from early childhood to young adulthood need further assessment.