Maxillomandibular Fixation

“The Jaw-Dropping Experience of a Lifetime”

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

ClientJeremy Warner, MD

Plastic Surgery, UW Medical School

AdvisorWilliam Murphy

Assistant Professor, Department of Biomedical Engineering

OutlineBackground InformationProblem StatementMotivationOur Client’s RequirementsDesigns for ProjectDecision MatrixGoals for ProjectQuestions

Background Information Mandible is the second most

fractured bone of the face Common causes of fractured

mandibles1. Assault2. Motor vehicle accidents3. Falls4. Sporting accidents

3 steps in fixing a mandible: realign bones, fixation, and rehabilitation

Problem StatementDesign 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

Motivation for ProjectSurgeons 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Maxillomandibular fixation is outdated requires wiring the mouth shut with the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 wiresMust be a better way!

Our Client’s RequirementsCost effectiveLight weightDynamicEmergency

release

No forces on front teeth

Time EffectiveSafe

Design #1: External Stabilization

Place support on head

Tighten straps securely

Design #1: Materials and CostsJaw brace

Estimated Price…$70

Design #1: Evaluation

ProsEasy

applicationCost effectiveQuick releaseNo anesthesia

ConsAestheticsDiscomfortSmall chance

of sliding off

Design # 2: Screws and Magnets

Figure 1

Figure 2

Figure 3

Magnets attached to screws

Drill screws into jaw

Use magnetic force to hold jaw together

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

Design #2: Evaluation

Pros Re-usable

materials (screws)

Quick Application

Durable

Cons No emergency

release Not aesthetically

pleasing Requires

anesthesia

Design #3: Braces

• Apply brackets• Connect lateralbrackets with elastic• Connect vertical bracketswith rubber bands

Figure 2

Figure 1

Design #3: Materials and Costs16 (stainless steel) brackets16 elastics (power chain) adhesive 8 rubber bands

Estimated Cost…$400 per application

Design #3: Evaluation

Pros Quick release Short

application time (approx. 15-20 minutes)

No anesthesia necessary

Aesthetically pleasing

ConsExpensive

Design 1: External

Design 2: Screws/Magnets

Design 3: Braces

Application Time 5 4 4

Cost 5 3 2

Quick Release 5 1 5

Aesthetics 1 2 5

Comfort 1 2 4

Durability 2 4 4

Local Anesthesia 5 1 5

Total 24 17 29

Scale: 1-5, 1=poor, 5=good

Decision Matrix

Goals for the Rest of the SemesterFind muscle forces in jawTest design on model skullFind exact price of braces design

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>.

ANY QUESTIONS?