3. Serial extractions – involves sequential removal of milk teeth and some permanent
teeth to bring remaining teeth of mixed dentition into favourable positions.
Commonly, deciduous canines, deciduous first molars and last erupting first
premolars is the sequence followed.
4. Correction of anterior and posterior cross bite – cross bite is when upper and lower
teeth are in reverse relation. Some cases can be corrected in early life itself, to prevent
jaws from getting reverse aligned in future. Correction can be done using some
appliances like Z spring, Tongue blade, Catalan’s appliance, expansion appliance like
quad helix.
5. Correction of open bite – this is a condition where there is no vertical overlap between
upper and lower teeth. Many appliances can be given here like headgear, chincup as
well as habit breaking ones like for thumb sucking, tongue thrusting etc.