OBJECTIVES:  We explore three-dimensional data to delineate idiosyncratic and progressive growth variation in 6.0-8.0 year old mandibles (n=45)

Lo, Vicki

Oh, Hee Soo

Richards, Gary D

Tran, Tiffany

English

Scholarly Commons

Geometric morphometric shape assessment of juvenile mandibles Tiffany Tran1*, Hee Soo Oh2, Vicki L. Lo1, and Gary D. Richards3 1Doctor of Dental Surgery Program, 2Department of Orthodontics, and 3Department of Biomedical Sciences, A. A. Dugoni School of Dentistry, University of the Pacific, San Francisco OBJECTIVES:  We explore three-dimensional data to delineate idiosyncratic and progressive growth variation in 6.0-8.0 year old mandibles (n=45).  METHODS: Thirty-nine landmarks were digitized. Using Morphologika we assessed shape using Principle Components (PC) Analysis on Procrustes-aligned shape variables.  RESULTS: PC 1-4 explain 18.5, 12.0, 9.6, and 8.0% of the variance, respectively. PC1 becomes positive between 6.0-6.5 years, stabilizing after 7.0 years.  This shows that the corpus-to-ramus angle becomes more obtuse between 6-7.0 years. Dimensions comprising PC1 stabilize but idiosyncratic variation increases between 7-8.0 years. PC2 shows little intergroup growth but a significant change in idiosyncratic variation related to corpus width. PC3 shows substantial lateral coronoid process growth and concomitant anterior chin progression related to idiosyncratic variation but little in the way of progressive age change.  CONCLUSIONS: Geometric morphometric methods allows visualization of the range of idiosyncratic variation in specific age groups but also the type and degree of shape change between minor increments of age.  This will was presented at the Annual Meeting of the California Dental Association, Anaheim, California May 17th-19th 2018.  

Geometric morphometric shape assessment of juvenile mandibles

https://scholarlycommons.pacific.edu/cgi/viewcontent.cgi?article=1058&context=excellence-day

Geometric morphometric shape assessment of juvenile mandibles

Abstract

Similar works

Full text

Available Versions

Scholarly Commons