World Journal of Dentistry

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VOLUME 9 , ISSUE 1 ( January-February, 2018 ) > List of Articles


Methodology for Stress Measurement by Transparent Dental Aligners using Strain Gauge

Mamta Juneja, Prashant Jindal, Divya Bajaj, Ishan Madhav, Rakesh Tuli

Citation Information : Juneja M, Jindal P, Bajaj D, Madhav I, Tuli R. Methodology for Stress Measurement by Transparent Dental Aligners using Strain Gauge. World J Dent 2018; 9 (1):13-18.

DOI: 10.5005/jp-journals-10015-1499

License: CC BY 3.0

Published Online: 01-02-2018

Copyright Statement:  Copyright © 2018; The Author(s).



Orthodontic tooth movement is a pressing issue nowadays. An increased esthetic demand during orthodontic treatment has resulted in several alternative treatments. However, the need to avoid conventional fixed orthodontic prosthesis has led to the usage of computer-aided scanning, imaging, and printing technology along with the emergence of transparent dental aligners. The motive of this study is to present methodology of measurement of the stress applied by transparent dental aligners on human teeth using a strain gauge-based measurement device.

Materials and methods

Three dimensional (3D) scanner, 3D printer, thermoforming machine, strain gauge, data acquisition device, 3Shape Ortho Analyzer software were used.


For a full-bridge Wheatstone bridge data acquisition system (DAQ), a standard aligner can strain a constantan-based strain gauge by nearly 2.5 × 10—4. This is based on the strain gauge factor of 2, input voltage 5 V for which a change in voltage of 2.5 mV was detected. Young's modulus for constantan strain gauge is given as 17.5 MPa; hence, this produced a stress of nearly 4.38 × 10—3 MPa.


This article describes an effective and convenient methodology for orthodontic treatment design for patients with crowding problem using computer-aided design (CAD) and computer-aided manufacturing (CAM) software and, thereafter, printing different stages of maxilla and mandible using fused deposition modeling (FDM) rapid prototyping technique. A transparent aligner is fabricated using thermoforming process, and the applied stresses on manipulated teeth by aligner can be evaluated using a strain gauge-based DAQ.

Clinical significance

This approach is expected to understand the efficacy of the thermoformed aligners for teeth movements by calculating applied forces and stresses.

How to cite this article

Bajaj D, Madhav I, Juneja M, Tuli R, Jindal P. Methodology for Stress Measurement by Transparent Dental Aligners using Strain Gauge. World J Dent 2018;9(1):13-18.

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