Prospective clinical trial comparing the effects of conventional Twin-block and mini-block appliances: Part 2. Soft tissue changes.

Purpose: The aims of this prospective clinical trial were to compare the soft tissue effects of Twin-block (TB) and mini-block (MB) functional appliances by using lateral cephalograms and optical surface laser scans and to evaluate the extent of posttreatment relapse with both appliances.

Material: Seventy Class II Division 1 patients meeting set inclusion criteria were matched by age and sex. The matched pairs were randomly allocated to treatment with either the TB or the MB appliance.