Tooth-borne vs bone-borne rapid maxillary expanders in late adolescence

Area of Science:

• Orthodontics
• Craniofacial Development
• Biomaterials

Background:

• Rapid maxillary expansion (RME) is a common orthodontic treatment for transverse discrepancies.
• Traditional tooth-borne expanders can lead to undesirable dentoalveolar side effects.
• Bone-borne expanders offer a potentially more orthopedic approach to RME.

Purpose of the Study:

• To compare the immediate skeletal and dentoalveolar effects of bone-borne (C-expander) versus tooth-borne (Hyrax) rapid maxillary expansion (RME).
• To evaluate changes in transverse dimensions, alveolar bone, and tooth angulation using cone-beam computed tomography (CBCT).
• To assess side effects such as buccal dehiscence in late adolescents.

Main Methods:

• A sample of 28 female late adolescents underwent RME with either a bone-borne (n=15) or tooth-borne (n=13) expander.
• CBCT scans were acquired before (T1) and 3 months after (T2) RME.
• Transverse skeletal and dental changes, alveolar inclination, tooth axis, vertical height, and buccal dehiscence were analyzed.

Main Results:

• Bone-borne expanders achieved greater skeletal expansion compared to tooth-borne expanders, with fewer instances of alveolar bone tipping.
• Tooth-borne expanders resulted in more buccal tipping of alveolar bone and tooth axes.
• Similar dental expansion at the apex level was observed for both expander types in banded teeth; however, the tooth-borne group showed significant buccal dehiscence at the first premolar.

Conclusions:

• Bone-borne expanders provide more significant orthopedic effects in late adolescents undergoing RME.
• Compared to tooth-borne expanders, bone-borne devices are associated with fewer dentoalveolar side effects.
• CBCT analysis is crucial for evaluating the precise skeletal and dentoalveolar outcomes of RME.