Typically, multi-phase treatment is offered for children and teenagers when growth modification is necessary; or if dental correction is beneficial at an earlier age.
Early expansion and growth modification can often convert surgery cases into mere extraction cases. Early treatment can transform some extraction cases into simple expansion cases, and in rare cases may eliminate the need for full braces all together.
Although some patients are able to avoid full braces (the second phase) as a result of early care, this is the exception to the rule. If a child has a condition serious enough to call for treatment at age seven, it is almost certain that he or she will need to have their treatment finished in a second phase once all of the permanent teeth have come in.
Some examples of Phase 1 treatment include removable retainers, partial braces, space maintainers, expanders and/or headgears.