J Korean Acad Prosthodont.  2011 Oct;49(4):324-332. 10.4047/jkap.2011.49.4.324.

Finite element analysis of the effects of mouthguard produced by combination of layers of different materials on teeth and jaw

• So WS
• Lee HJ
• Choi WJ
• Hong SJ
• Ryu KH
• Choi DG

• KMID: 2195527
• DOI: http://doi.org/10.4047/jkap.2011.49.4.324

Abstract

PURPOSE
The purpose of this study was to compare the stress distribution of teeth and jaw on load by differentiating property of materials according to each layer of widely used mouthguard.
MATERIALS AND METHODS
A Korean adult having normal cranium and mandible was selected to examine. A customized mouthguard was constructed by use of DRUFOMAT plate and DRUFOMAT-TE/-SQ of Dreve Co. according to Signature Mouthguard system. The cranium was scanned by means of computed tomography with 1mm interval. It was modeled with CANTIBio BIONIX/Body Builder program and simulated and interpreted using Alter HyperMesh program. The mouthguard was classified as follows according to the layers. (1) soft guard (Bioplast)(SG) (2) hard guard (Duran)(HG) (3) medium guard (Drufomat)(MG) (4) soft layer + hard layer (SG + HG) (5) hard layer + soft layer (HG + SG) (6) soft layer + hard layer + soft layer (SG + HG + SG) (7) hard layer + soft layer + hard layer (HG + SG + HG) The impact locations on mandible were gnathion, the center of inferior border, and the anterior edge of gonial angle. And the impact directions were oblique (45degrees). The impact load was 800 N for 0.1 sec. The stress distribution was measured at maxillary teeth, TMJ and maxilla. The statistics were conducted using Repeated ANOVA and in case of difference, Duncan test was used as post analysis.
RESULTS
In teeth and maxilla, the mouthguard contacting soft layer of mandibular teeth presented lowest stress measure and, in contrast, in condyle, the mouthguard contacting hard layer of mandibular teeth presented lowest stress measure.
CONCLUSION
For all impact directions, soft layer + hard layer + soft layer, the mouthguard with three layers which the hard layer is sandwiched between two soft layers, showed relatively even distribution of stress in impact.

Keyword

FEM analysis; Mouthguard; Stress distribution; Soft layer; Hard layer

MeSH Terms

Adult
Finite Element Analysis
Humans
Jaw
Mandible
Maxilla
Skull
Temporomandibular Joint
Tooth

Figure

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  Fig. 1. The scheme of 7 kinds of mouthguard materials.

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  Fig. 2. Loading points on mandible.

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  Fig. 3. Measuring points.

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