Maxillomandibular Fixation

1. Maxillomandibular Fixation “The Jaw-Dropping Experience of a Lifetime”

2. Our Team From left to right… • Emily Maslonkowski (BSAC) • Ashley Phillips (Co-Team Leader) • Nina Lewis (Co-Team Leader) • Sara Karle (BWIG) • Joe Ferris (Communications)

3. Client • Jeremy Warner, MD • Plastic Surgery, UW Medical School

4. Advisor • William Murphy • Assistant Professor, Department of Biomedical Engineering

5. Outline • Background Information • Problem Statement • Motivation • Our Client’s Requirements • Designs for Project • Decision Matrix • Goals for Project • Questions

6. Background Information • Mandible is the second most fractured bone of the face • Common causes of fractured mandibles • Assault • Motor vehicle accidents • Falls • Sporting accidents • 3 steps in fixing a mandible: realign bones, fixation, and rehabilitation

7. Problem Statement • Design a device which will: • Fixate the top of the mouth to the jaw • Be easier and faster to apply • Maintain an adequate cost of application • Be safe for the 4-6 weeks of healing

8. Motivation for Project • Surgeons throughout history have dealt with broken mandibles in many ways • Maxillomandibular fixation is outdated • requires wiring the mouth shut with the use of arch bars and wires • Must be a better way!

9. Cost effective Light weight Dynamic Emergency release No forces on front teeth Time Effective Safe Our Client’s Requirements

10. Design #1: External Stabilization • Place support on head • Tighten straps securely

11. Design #1: Materials and Costs • Jaw brace Estimated Price…$70

12. Design #1: Evaluation • Cons • Aesthetics • Discomfort • Small chance of sliding off • Pros • Easy application • Cost effective • Quick release • No anesthesia

13. Design # 2: Screws and Magnets Figure 3 • Magnets attached to screws • Drill screws into jaw • Use magnetic force to hold jaw together Figure 2 Figure 1

14. Design #2: Materials and Costs • 4 Titanium Cortical Screws • 4 AlNiCo Magnets • Centre Drive Hexagonal Screwdriver (one-time cost) Estimated Cost...$103.36-$110.56 per application

15. Pros Re-usable materials (screws) Quick Application Durable Cons No emergency release Not aesthetically pleasing Requires anesthesia Design #2: Evaluation

16. Design #3: Braces Figure 1 • Apply brackets • Connect lateral • brackets with elastic • Connect vertical brackets • with rubber bands Figure 2

17. Design #3: Materials and Costs • 16 (stainless steel) brackets • 16 elastics (power chain) • adhesive • 8 rubber bands Estimated Cost…$400 per application

18. Design #3: Evaluation • Cons • Expensive • Pros • Quick release • Short application time (approx. 15-20 minutes) • No anesthesia necessary • Aesthetically pleasing

19. Decision Matrix Scale: 1-5, 1=poor, 5=good

20. Goals for the Rest of the Semester • Find muscle forces in jaw • Test design on model skull • Find exact price of braces design

21. References • Goldman, Kim E. "Mandible Fractures." Ask An Oral & Maxillofacial Surgeon. 2005. 8 Sept. 2005 <http://www.calweb.com/~goldman/mandible_fractures.html>. • "Muscles of Mastication: Form dictates function; Function follows form." Nociceptive Trigeminal Inhibition - Tension Suppression System. 15 Sept. 2005 <http://www.nti-tss.com/slide1.htm>. • Peltier, Jacques, comp. Mandible Fractures. 26 May 2004. UTMB Dept. of Otolaryngology. 11 Sept. 2005 <http://www.utmb.edu/otoref/Grnds/Mandible-fx-040526/Mandible-fx- 040526.htm>. • Prater, Michael E., comp. Mandibular Fractures. 27 Nov. 1996. UTMB Dept. of Otolaryngology. 20 Sept. 2005 <http://www.utmb.edu/otoref/Grnds/Mandibular-fx- 961127/Mandibular-fx-961127.htm>. • Stierman, Karen, and Byron J. Bailey. "Mandible Fractures." 14 June 2000. 10 Sept. 2005 <http://www.utmb.edu/otoref/Grnds/Mandible-fx- 0006/Mandible-fx-0006.pdf>.

22. ANY QUESTIONS?