IADR Abstract Archives

Tongue Postural Adaptations Occur with Damon Appliance Dental Arch Expansion

Objectives: Orthodontic arch development expands and broadens the dentition beyond the confines of the original arch perimeter. This is often accomplished by means of self-ligating fixed appliances. When movements take the teeth outside those confines, without adaption, the muscular forces are unbalanced and may lead to dental relapse. Muscle spindles and associated reflex loops within the tongue provide feedback to arch perimeter changes that may produce postural changes to the new archform.  Resting posture has long been accepted as aiding in tooth position. The objective of this study was to assess the oral and pharyngeal postural changes that result from arch development with the Damon system and report the amount of expansion accomplished.

Methods:   Pre- and post-treatment models and lateral cephalograms were collected on 69 previously treated orthodontic patients from four different private practices. Expansion was measured from the buccal cusp tips of the first and second premolars and first molars.  A new cephalometric analysis was implemented to diagnose both variations in malocclusion and variations in posture of the head, neck, pharynx, hyoid bone and tongue.

Results:   Both tongue height and length increased, 2.9mm (P-value 0.001, SEM=1.06) and 3.76mm (P-value 0.00002, SEM=0.62) respectively, following posterior dental arch expansion using Damon archwires. Hyoid position was not significantly different.  Average expansion at each tooth was as follows:

Mx:

1st Premolars

4.06mm

 

2nd Premolars

3.87mm

 

1st Molar

1.77mm

Md:

1st Premolars

2.8mm

 

2nd Premolars

2.67mm

 

1st Molars

1.08mm

Conclusion: As dental arches are expanded the tongue increases in both length and height to fill the space and therefore may aid in stability during the retention phase of treatment.  The lack of change in hyoid bone position, as one would expect with a rise in tongue position, might be explained by either slight changes in head position or the need to maintain the airway.

IADR/AMER General Session
2014 IADR/AMER General Session (Cape Town, South Africa)
Cape Town, South Africa
2014
491
Craniofacial Biology
  • Padilla, Mark  ( Temple University, Philadelphia, PA, USA )
  • Hashemi, Hamid  ( Temple University, Irwin, PA, USA )
  • Flagg, Brienne  ( Temple University, Wilmington, DE, USA )
  • Stacey, Andrew  ( University of Michigan, Ann Arbor, MI, USA )
  • Godel, Jeffrey  ( Temple University, Philadelphia, PA, USA )
  • Chialastri, Susan  ( Temple University, Philadelphia, PA, USA )
  • Sciote, James  ( Temple University, Philadelphia, PA, USA )
    • Poster Session
    Orthodontics: Treatment Factors and Outcomes
    06/26/2014