Can a palate expander fix a cleft palate?

Not it's job. Palatal expander used to widen a narrow upper jaw. It does not correct a cleft, but properly repositions the 2 halves of the upper jaw from side-to-side. Repair of the cleft usually means some surgery. Talk to the cleft team about what's being done and why.
No. A palatal expander helps get the child with a cleft palate ready for bone grafting to repair the hole in the gum line. The expander is used to align the gum line in the proper position. It is not used to fix the palate.
No. But it can be useful in positioning the right and left alveolar processes of the maxilla...Prior to surgical repair of the cleft.

Related Questions

How long will my seven year old need to wear a palate expander?

Expander. These are worn until your orthodontist sees the result(correction of a cross bite) needed for your child's treatment. Please consult with your orthodontist to have explained the result he or she is looking for and do not expand more than is recommended per day as it can cause more problems and pain. Read more...
1-2 years. Normally takes 1-2 years to expand the arch and then hold it in place while the bone fill in. Read more...
Orthodontist call. As long as necessary. The dental team who is treating your son will determine when the palatal expansion devise must be removed. It usually takes 4 to 6 months for it to do its job. Read more...

Help docs! I had my palate expander for 5 years. Will I have to get another palate expander?

Why? I see no earthly reason for wearing an appliance that long. Once the 2 halves of the upper jaw fuse there is no way to correct transverse skeletal discrepancy without surgery. Please seek consultation with one or more qualified orthodontic specialists rather than with well meaning but under-trained dentists who dabble in "tooth movement" which is not synonymous with "orthodontic treatment.". Read more...
Too long. A palette expander is typically worn for weeks, not years and is typically not used too many years into adulthood. Read more...