Dr. Vo Danh M. Nguyen, a 2009 graduate of the University of Florida College of Dentistry Orthodontic program, won 3rd place in the basic science category of the Charley Schultz Resident Scholar Award Competition sponsored by Dentsply GAC at the recent American Association of Orthodontics (AAO) annual meeting in Boston.
Nguyen presented his Masters of Science research entitled “Increased Vertical Dimension (VDO) Effects on Masseter Muscle Phenotype During Maturation” and competed against both American and International Orthodontic residents. Only one resident from each university is chosen to compete in this prestigious competition. The 3rd place award included a prize of $500. Drs. Charles Widmer and Joyce Morris-Wiman served as mentors for this project.
Congratulations to Nguyen!
A synopsis of Nguyen’s research:
Increased Vertical Dimension (VDO) Effects on Masseter Muscle Phenotype During Maturation
Vo Danh M. Nguyen, University of Florida
Select orthodontic cases are facilitated by increasing the VDO. However, it is unclear how jaw closing muscles adapt to these changes. Our objective was to determine if an increase in VDO affected myosin heavy chain (MyHC) protein expression in a maturing animal. Six CD-1 male mice (age 6 weeks) underwent a 10% bite opening; 6 age-matched control mice had a sham procedure. Animals were sacrificed at days 7 and 14. Masseter 14m cryosections were immunostained for MyHC IIa and IIb. In anterior and posterior (superficial, intermediate and deep) areas, MyHC fiber type and diameters were determined. In controls, MyHC expression changes in post-intermediate and post-deep regions occurred within the 14-day maturation (IIa: -34%, -25%; IIb: +18%, +21%; ANOVA, p<0.05). With bite opening, these changes did not occur compared to controls (p<0.05). These data are consistent with bite opening inhibition of male muscle maturational changes in directly affected, vertically oriented muscle fibers.