Impact Measurements on Teeth and Mouth Guard. Mouth Guard
Dentures
In sporting event like Boxing, Hockey and Cricket, invariably the players face jaw injuries due to the impact of the ball at high speed.
Hence use of mouth Guard is highly recommended for these players especially for Boxing. In Boxing use of the mouth Guard during the match is mandatory.
Studies are conducted to study the impact of these balls on the teeth and the effect of the mouth guard in absorbing the impact energy. TEST RIG.
The Test Rig Consists of a Pendulum with a Ball Fixed at the bottom.
The ball – Cricket or Hockey or Steel Ball can be replaced easily by removing the nut.
The Denture is fixed on a base plate.
The length of the pendulum is 50 cms.
The Pendulum is first fixed horizontally by a handle and then released to hit the dentures.
The cricket and hockey balls are of 78 mm diameter and the steel ball 37 mm.
Weight:- Hockey Ball = 120 gms, Cricket Ball = 130 gms and Steel Ball = 210 gms.
350 Ohms Strain Gage Bonded at the Centre of the Denture TEST SET UP.
PENDULUM
NOTEBOOK PC WITH USB DAQ HOCKEY BALL
SCAD 500 STRAIN MEASUREMENT SYSTEM The strain gage bonded on the dentures is interfaced to the SCAD 500 Strain Measurement System. The Dynamic Response of SCAD 500 is 150 KHz. The output is interfaced to the USB DAQ ( Maximum Sampling Rate = 20 KHz).
Probably a DAQ with Higher sampling Rate is needed. TEST RESULTS.
Impact Measurements on the Dentures (without the Mouth Guard) with a Hockey Ball
STRAIN VS TIME - HOCKEY BALL MICROSTRAIN
-200
-300
-400
-500
-600
-700
-800
-900
-1000
25.850 25.855 25.860 25.865 25.870 25.875 HOCKEY BALL [MICROSTRAIN] s Impact Measurements on the Dentures (with the Mouth Guard) with a Hockey Ball STRAIN VS TIME - HOCKEY BALL MICROSTRAIN
-200
-300
-400
-500
-600
-700
-800
-900
-1000
12.540 12.545 12.550 12.555 12.5 6 The HOCKEYmaximum BALL [MICROSTRAIN] strain during impact with the mouth guard reduces from -600 to -500 microstrain. Thiss clearly shows that the mouth guard absorbs good amount of energy during impact. Impact Measurements on the Dentures (without the Mouth Guard) with a Cricket Ball STRAIN VS TIME - CRICKET BALL MICROSTRAIN
-200
-300
-400
-500
-600
-700
-800
-900
-1000
1.98101.9820 1.9815 1.9825 1.9830 1.9835 1.9840 1.9845 1.9850 1.9855 1.9860 1.9865 1.9870 CRICKET BALL - NO PROTE [MICROSTRAIN] s Impact Measurements on the Dentures (with the Mouth Guard) with a Cricket Ball
STRAIN VS TIME - CRICKET BALL MICROSTRAIN
-200
-300
-400
-500
-600
-700
-800
-900
-1000
22.230 22.235 22.240 CRICKET BALL - NO PROTE [MICROSTRAIN] s The maximum strain during impact with the mouth guard reduces from -980 to -600 microstrain. This clearly shows that the mouth guard absorbs good amount of energy during impact. Impact Measurements on the Dentures (without the Mouth Guard) with a Steel Ball
The steel ball is used to simulate impacts during Boxing.
The dentures got damaged during the hit (without the mouth guard) and cracked at the place where the strain gage was mounted. So strain at the centre could not be emasured.
So another strain gage in the neighboring tooth was bonded
New Strain Gage
Damaged Areas Impact Measurements on the Dentures (without the Mouth Guard) with a Steel Ball
STRAIN VS TIME - HOCKEY BALL MICROSTRAIN
1000
900
800
700
600
500
400
300
200
3.120 3.125 3.130 METALLIC BALL [MICROSTRAIN] s The Neighboring tooth under impact shows a Tensile Strain Impact Measurements on the Dentures (with the Mouth Guard) with a Steel Ball
STRAIN VS TIME - HOCKEY BALL MICROSTRAIN
1000
900
800
700
600
500
400
300
200
100
3.0603.070 3.065 3.075 3.080 3.085 3.090 3.095 3.100 3.105 3.110 3.115 METALLIC BALL [MICROSTRAIN] s
The maximum strain during impact with the mouth guard reduces from 500 to 275 microstrain. This clearly shows that the mouth guard absorbs good amount of energy during impact. CONCLUSIONS
Impact measurements on the Dentures with and without the mouthguard have been carried out using Hockey, Cricket and Steel Ball.
The maximum strain will be at the point of impact.
For these measurements a DAQ of Sampling Rate (200KHZ) is needed.
It is also important to study the strain distribution on the dentures at different tooth,
However it is not practically feasible bond several strain gages due to space limitations.
Hence for Strain Distribution use of Bragg Gratings is highly recommended.
Since the frequency response of the Bragg Grating Interrogator needs to be very high. Instead a Optical Spectrum Analyser could be a alternate.
The output of the OSA can be used to compute the percent energy absorbed by the Mouth Guard.
Further Studies using FBG will be Carried out at CSIO – Chandigarh. For More Detailed Information Please contact us at
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