Did MARPE at 27 with an oral surgeon. Nasal breathing improved dramatically and my smile widened. The surgical route is the only legitimate one for adults.

Widening the upper jaw after skeletal maturity
Using a removable or fixed palate expander — ranging from professional MSE (Maxillary Skeletal Expander) with surgical assist, to over-the-counter or DIY devices — to widen the upper jaw in adults. Professionally performed MARPE/MSE is a legitimate, if invasive, orthodontic procedure that can widen the nasal airway and create space for teeth. WARNING: DIY or unsupervised palate expansion carries serious risks — uneven force distribution can cause tooth tipping, root damage, asymmetric expansion, and TMJ problems. The mid-palatal suture increasingly fuses through the 20s; meaningful expansion without surgical assist becomes less viable and more risky with age. Only pursue through a board-certified orthodontist or oral surgeon.
2 verified voices, averaging 2.5 of 5.
Did MARPE at 27 with an oral surgeon. Nasal breathing improved dramatically and my smile widened. The surgical route is the only legitimate one for adults.
Tried an OTC expander after watching YouTube videos. Created a gap between my front teeth that required expensive orthodontic correction. Go professional or don't go at all.