Enamel matrix 3D organization and maturation stage ion flow

As part of the subcontract, Prof Joester and a graduate student (to be named later) will work towards determining similarities and differences in enamel nanostructure of wildtype and amelogenin knockout mice. All work involving vertebrate animals and cellular biological tissues will be performed at the Forsyth Institute, by members of the Bidlack group and collaborators. Teeth extracted from wildtype and knockout mice will be cleaned, fixed, and sent by mail to Northwestern University. At NU, Prof. Joester and the student will a) prepare samples for atom probe tomography by methods developed in the Joester lab; including, but not limited to, embedding, grinding and polishing, and focused ion beam-based liftout of samples of APT and TEM. b) perform APT experiments at the Northwestern University Center for Atom Probe Tomography (NUCAPT). This includes extensive optimization of run time parameters. c) analyze atom probe data sets and visualize the data, using commercially available tools and software developed in the Joester lab. d) quantitatively compare structure and composition of enamel from WT and KO mice. In particular, we will determine the dimension and chemical composition of the hydroxylapatite nanowires, and of grain boundaries and grain boundary precipitates. Where appropriate, we will use statistical tools suited to comparing samples. e) assist Dr. Bidlack and her team in interpreting the resulting data, writing reports and publications, and presenting results at conferences, meetings, and workshops.