IS THE TONGUE IS MORE THAN A DENTAL OBSTACLE?Presentation Transcript
IS THE TONGUE IS MORE THAN A DENTAL OBSTACLE? Department of OCBS and Orthodontics University of Maryland Dental School Baltimore This research was supported in part by grant DC02561 from the National Institute of Deafness and Other Disorders Maureen Stone, Ph.D.
At first, the bolus depresses the anterior tongue (red).
The bolus is transported backward.
The tongue elevates A-to-P as the bolus is squeezed backward.
Blue = high, Red = low regions Unrestrained– 20 ml BACK_ _ _ _ _ _ _ _ _ _FRONT Time Height 3 2 1
Unrestrained 10 mm BB Pos_ _ _ _ _ _ _ _ _ _ _Ant Time Height The biteblock caused a more anterior tongue initially (blue), a lower depression during propulsion (yellow), and a more anterior final closure (blue). Time Height Time
The initial and final closures were more anterior in BB than unrestrained (red arrows). Perhaps the subject could only reach a more anterior (and lower) part of the palate. The overlay shows the tongue to be anterior and inferior in the BB case. time unrestrained 10 mm BB
Effect of Bolus Size: Unrestrained Jaw 5ml vs 20 ml water
The patterns are very similar. The larger bolus depresses more deeply in the front around the bolus (red). Also the tongue elevates more rapidly to achieve maximum closure. 5ml 20ml
Swallowing patterns were similar for 2 bolus sizes. The 20 ml bolus begins with greater anterior tongue lowering, but both swallows end in the same place, with full palate contact. Thus pattern differences werere primarily scalar. 20 ml 5 ml time tongue palate contact
Study 2. Effect of Mouth Breathing on Tongue Position
Breathe normally for one minute (NO).
Breathe with nose clamped for one minute (NC).
Breathe with nose clamped and tongue held forward for one minute (NCANT).
Ultrasound images of midsagittal tongue contour.
Contour measured as x,y coordinates.
Displayed in Excel.
Mouth Breathing Results
Subjects 1 and 2 were similar.
NC caused tongue lowering .
NCANT caused anterior tongue position.
Subject 3 was different.
NC caused backward tongue rotation .
NCANT caused anterior tongue root .
All opened their airways more in NCANT than NC.
NO NC NCANT
Tongue motion is complex in three dimensions.
Tongue segments are uncorrelated due the tongue’s anisotropic muscle architecture.