Are Removable Palate Expanders As Effective As Fixed Ones?

You have a great question that deserves a straight answer.  First of all, slow palatal expansion (SPE) with a removable treatment appliance is not new.  I have personally been successfully been using this technique for the past 28 years and have patients successfully expanded well past their 70th birthday.  Contrary to popular belief in the dental community, the mid-palatal suture does not fuse in 99+% of the cases allowing significant bone expansion at any age without surgery.  The key is to have physiologic expansion with a removable appliance putting pressure to the roof of the mouth, not the teeth and using no more than 2-3 activations (1/4 mm each) per week.  And yes, this does open up the airway to increase nasal breathing capacity. It also can help correct your Class III and provide more room for the tongue, and more stability to avoid an open bite.  

Fixed expanders can't work well to get large amounts of expansion, needed in many extreme cases, because the pressure is placed on the teeth, not the roof of the mouth, and the roots of the teeth can go through the bone structure when large amounts of activations are needed.  Also, RPE (rapid palatal expansion with daily activations) is not physiologic.  The bone cannot adapt to such rapid movements.  Tell your dentist/orthodontist about my book "Straight Talk about Crooked Teeth" for more detail if they are open to learning about  a very well tested (over 5000 cases) method, to avoid the traditional approach of surgery and extractions.

 Doctors who treat sleep apnea and TMJ disorders frequently find themselves trying to reverse bicuspid extraction orthodontics.It is important to establish goals of the  therapeutic correction of physiologic and esthetic issues. Functional Appliances are not new.  They have been around for a very long time and have primarily been used in children and adolescents.  What is new is the field of Epigenetic Orthodontics and the DNA Appliance that effectively grows maxilla at any age with part-time wear (12-14 hours/day) The ALF appliance work with very light forces and can expand an arch but when trying to achieve orthopedic growth the functional Appliances are more effective. The DNA Appliance and Epigenetic Orthodontics use light forces and is only worn 12-14 hours a day. The time the appliance is out mimics what happens with normal eruption of natural teeth.The DNA Appliance  has been shown in clinical casesto cure sleep apnea but large scale studies are early and pending. The DNA Appliance is very effective in growing the maxilla . It is most likely to need less long term retention but erring on side of longer retention is never a bad idea.Putting aside the idea of extraction reversal and looking at therapeutic goals is always the best approach.The SARPE procedure with Rapid Palatal Expansion with a Surgical Assist is also a viable option but does need longer retention.Ira L Shapira DDSDiplomate, American Board of Dental Sleep MedicineDiplomat, American Acdemy of Pain ManagementRegent & Fellow, International College of CranioMandibular OrthopedicsChair, American Alliance of TMD OrganizationsThinkBetterLife.com

Although some arch expansion can be achieved in 20-year-olds using removable appliances (be it a retainer with an expansion screw or Invisalign), all of that movement will be dental-only - meaning the teeth will move but the jaw bones will not. The only way you would see improve respiration due to enlarging the nasal passage at age 20 would be to combine a fixed palatal expander with a surgical procedure to re-open the suture in the roof of your mouth. As for the openbite, it is true that most expansion techniques DO tend to open the bite.