I often get questions about maxillary expansion, so I though this may help doctors.
- Make sure to diagnose your patient’s case properly. Measure from skeletal and not from dental landmarks. Use the WALA measurements. Often the lower posterior segment is lingually tipped, creating a situation where you may think you need less expansion than you really do. Remember, the lower arch dictates the amount of expansion you need or can/should do.
- Know your limits. Make sure that you need expansion and not SARPE. After a certain point, the palatal suture fuses and expansion requires surgery (SARPE or MARPE).
- Use the proper expander to maximize skeletal expansion (Good), and to minimize dental tipping (Very Bad). If there is an anterior cross-bite also with a posterior cross-bite, bonded expanders can help because they open the bite so there is room for the anterior teeth to cross over while the posterior expansion is being completed.
- If a young patient (=< CVM 3) has a retrognathic maxilla, the time of expansion can be the best way to correct the maxillary AP (anterior-posterior) with a face-mask. Of course, know your limits. After age 12 the face mask results can be unpredictable.
- Know, and be sure of how much expansion you need. Over expansion can be corrected more easily than under-expansion. If you miscalculate your expansion needs, you can over expand the arch so much that you will have a buccal cross-bite (scissors bite) which is very very hard to correct. A little over expansion can be allowed to relapse easily, but under expansion requires to place the expander back and continue expansion (time waster).
- Retention: make sure to retain your expansion during treatment (TPA/Gosh), and after treatment (often Hawley is better vs clear overlay to hold a posterior arch and the transverse).
I hope this help with your expansion cases.
We cover the details of maxillary expansion in our Orthodontic Mini-Residency, and in our 1 day intro to Orthodontics NOA 101 courses. We hope to see you there if you need more help.
https://nagyorthodonticacademy.com/events/
Best of luck.