Thermographic characterization of masticatory muscle regions in volunteers with and without myogenous temporomandibular disorder: preliminary results

Abstract

Objectives: This study aims to conduct a non-invasive measurement of the cutaneous temperature of selected masticatory muscle regions of volunteers with and without myogenous temporomandibular disorder (TMD), using infrared thermography. Methods: 23 females (10 myogenous TMD volunteers and 13 controls) were recruited and studied. The temperature at the surface of the facial area over the anterior temporalis and masseter muscles was assessed by medical thermography, using regional lateral views and clinical examination. Results: The temperature levels measured at the masseter and anterior temporalis muscle regions in myogenous TMD volunteers (32.85 ± 0.85 and 34.37 ± 0.64 ºC, respectively) were significantly lower (p , 0.05) than those measured in controls (33.49 ± 0.92 and 34.78 ± 0.44 ºC, respectively). Medical infrared imaging indicated a mean difference of 1.4 ºC between the masseter and anterior temporalis regions. Analysis of the comparison between the absolute and normalized mean temperatures was performed using the pairwise comparison of receiver operating characteristic curves, and no statistically significant difference was observed (p . 0.05). The sensitivity and specificity of the thermographic assessment for the masseter region was of 70% and 73%, respectively and for the anterior temporalis region was of 80% and 62%, respectively. Conclusions: This method of evaluating masticatory muscle regions of this preliminary study seems to indicate that it can be used as an aid in complimentary diagnosing of TMDs. Dentomaxillofacial Radiology (2014) 43, 20130440. doi: 10.1259 Cite this article as: Haddad DS, Brioschi ML, Vardasca R, Weber M, Crosato EM, Arita ES. Thermographic characterization of masticatory muscle regions in volunteers with and without myogenous temporomandibular disorder: preliminary results.

A new evaluation of heat distribution on facial skin surface by infrared thermography

“…Its principle of image formation is based on the capture and transformation of infrared radiation emitted by the human skin, into images that reflect the microcirculatory dynamics of the skin surface. 1,4,5,7,8,10,11,15,16,[19][20][21][22][23][24][25][26] In spite of various articles having approached the thermographic examination as a promising method in dentistry, 8,[10][11][12]15,16,21,27 in the world literature, up to now, there is no standardization as regards the evaluation of thermograms of the face.…”

“…This temperature affects the two sides of the body uniformly and simultaneously, resulting in thermal symmetry. 4,5,7,8,10,15,16,[20][21][22]25,27 The parameters for thermography exams are internationally defined, in order to obtain images in the nearest state of thermal equilibrium between the body skin surface and the room temperature, without shivering or sweating while the images are captured. The parameters suggested for the interpretations and evaluation of the thermograms influenced at the same way because all the volunteers were at the same environmental conditions during the images capture.…”

“…These results corroborate values found in the literature consulted, because the DT patterns considered normal for the face are ,0.3°C. 2,6,8,[10][11][12]15,16,20,22 The thermal study of small regions is more faithful than that of larger regions, because the greater the image resolution (e.g. : 76,000 pixels) of the thermographic machine sensor the better will be the capacity of identifying the changes in temperature in small regions.…”

“…Many diagnoses of diseases that affect the facial region are made by imaging methods; however, conventional technique shows a lack of information as regards functional aspects, such as regional microcirculation and the autonomous nervous system. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] Thermography is a non-invasive diagnostic imaging method used in medicine, capable of detecting, recording and producing infrared images that reflect the microcirculatory dynamics of the skin surface of individuals in real time, comprising the vascular, nervous and musculoskeletal systems, in addition to inflammatory processes, as well as endocrine and oncological conditions. 1 In order to maintain normal thermoregulation, the neurovegetative central nervous system, by means of the hypothalamus, controls the skin blood flow in a uniform and symmetrical manner, resulting in a right/left thermal pattern that is also symmetrical.…”

“…Furthermore, the examination allows greater precision in thermal quantification and monitoring of the region of interest (ROI). 15,16 Various articles [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] have evaluated thermographic quantitative changes in facial skin vasomotor neurovegetative activity, that is, they calculated the absolute temperature of the ROI and conjugated gradients. However, few researches have demonstrated a standardization in the protocol of descriptive evaluation of normal facial thermal distribution of human beings.…”