Changes in jaw relations, hyoid position, and head posture in complete denture wearers

Area of Science:

• Dentistry
• Orthodontics
• Biomechanics

Background:

• Immediate complete dentures are used for partially edentulous patients.
• Mandibular repositioning and ridge resorption can affect craniofacial structures.
• Understanding hyoid bone and craniocervical posture changes is crucial for denture success.

Purpose of the Study:

• To examine changes in hyoid bone position and craniocervical posture in patients with immediate complete dentures.
• To correlate these changes with mandibular repositioning due to ridge resorption over one year.

Main Methods:

• Cephalometric radiographs were taken over a 1-year period for 18 partially edentulous patients.
• Measurements focused on hyoid bone position and craniocervical posture.
• Analysis included mean changes and individual variations.

Main Results:

• Hyoid bone position changes generally followed mandibular forward-upward rotation from ridge resorption.
• A mean increase in hyoid position relative to the cervical spine was observed.
• No significant mean changes in head and cervical column posture were detected.
• Individual analysis revealed cervical retroclination and decreased craniocervical angulation with significant mandibular inclination decrease.

Conclusions:

• Hyoid bone position adapts to mandibular changes induced by immediate complete dentures and ridge resorption.
• Craniocervical posture may exhibit adaptive retroclination in response to significant mandibular repositioning.
• These findings highlight the complex interplay between denture use, mandibular dynamics, and head posture.