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 Table of Contents  
ORIGINAL ARTICLE
Year : 2020  |  Volume : 32  |  Issue : 4  |  Page : 335-340

Effect of hand-held mobile phones on the parotid gland: A cross sectional study


Department of Oral Medicine and Radiology, Madha Dental College and Hospital, Kundrathur, Chennai, Tamil Nadu, Ind, India

Date of Submission20-Aug-2020
Date of Decision19-Oct-2020
Date of Acceptance23-Oct-2020
Date of Web Publication28-Dec-2020

Correspondence Address:
Dr. G Jeevitha
12 A, River View Apartments, 1st Crescent Park Road, Gandhi Nagar, Adyar, Chennai - 600 020, Tamil Nadu
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jiaomr.jiaomr_176_20

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   Abstract 


Background: The mobile phones widely used today uses electromagnetic radiations for signal transmission. These radiations have been speculated to cause pathological changes, especially in the salivary glands. Aim: The aim of the present study was to compare the salivary flow rate, pH, total protein concentration, Immunoglobulin A, total antioxidant capacity and salivary amylase levels of the parotid saliva between the dominant and non-dominant sides of mobile phone usage. Settings and Design: A total of 40 participants who used hand-held mobile phones were selected for the study. Materials and Method: Group A comprised of participants who used mobile phones for 0-2 hours a day, group B comprised of participants who used mobile phones for 2-4 hours a day and group C comprised of participants who used mobile phones for more than 4 hours a day. The parotid salivary pH, total protein concentrations, immunoglobulin A (IgA), salivary amylase, and total antioxidant capacity were estimated. Statistical Analysis: One-way ANOVA, Tukey HSD test and Pearson's correlation were used. Results: There was an increase in the mean salivary flow rate, pH and salivary IgA levels on the dominant side of participants. The mean total protein levels and IgA levels in the dominant sides of group A, B and C was 22.56 ± 9.35, 20.10 ± 4.95, 17.44 ± 4.52 and 3.39 ± 0.62, 5.03 ± 0.72, 7.51 ± 1.17, respectively. There was a decrease in the mean total protein, amylase and total antioxidant capacity in the dominant side. Conclusion: Our study has shown an increase in the levels of salivary flow rate, pH and IgA in the dominant side of usage.

Keywords: Hand-held mobile phone, immunoglobulin A, parotid saliva, salivary amylase, total antioxidant capacity


How to cite this article:
Jeevitha G, Anuradha G. Effect of hand-held mobile phones on the parotid gland: A cross sectional study. J Indian Acad Oral Med Radiol 2020;32:335-40

How to cite this URL:
Jeevitha G, Anuradha G. Effect of hand-held mobile phones on the parotid gland: A cross sectional study. J Indian Acad Oral Med Radiol [serial online] 2020 [cited 2021 Jan 22];32:335-40. Available from: https://www.jiaomr.in/text.asp?2020/32/4/335/305271




   Introduction Top


Oral health is integral to general health so that it contributes to the overall wellbeing of all individuals. At times, it's not only the pathological changes that can affect the effective functioning of the oral cavity, even external factors like the use of hand-held mobile phones can cause the physiology to undergo derangements. The electromagnetic radiations emitted by hand-held mobile phones have been studied time and again by various researchers who have observed an increased risk of malignant gliomas, acoustic neuromas, and tumors that occurred on the side of head where the mobile phone is routinely placed.[1] The salivary glands are the primary structures found in close proximity to the placement of mobile phones.[2] Considering the location of the parotid salivary gland and the fact that it lacks physical protection of any bony structures around it, it is evident that the parotid glands are highly influenced by the mobile phones and their electromagnetic radiation spectrum.

The aim of the present study was to compare the salivary flow rate, pH, total protein concentration, Immunoglobulin A, total antioxidant capacity and salivary amylase levels of the parotid saliva between the dominant and non-dominant sides of mobile phone usage.


   Materials and Method Top


The present cross-sectional study was conducted in the outpatient Department of Oral Medicine and Radiology. The study was approved by the Institutional Ethical Committee of our Institution, Madha Dental College and hospital, Somangalam road, Kundrathur, Chennai, Tamil Nadu with letter no. (MDCH/MDS/EC/- 016 dated 26/04/2017). We obtained a sample size of 40 subjects. The nature of the study was explained and all the participants signed the informed consent. We have obtained the prevalence of hand-held mobile phone users by keeping the alpha error value at 5% and a power of 80%. The study was conducted in accordance with the ethical principles of the Declaration of Helsinki (2013). All the participants were included in the study group. For each participant, the side of maximum placement of mobile phone was considered as dominant side and the side of remarkably less usage was considered as the non-dominant side. A brief history of the hand-held mobile phone usage was asked and a preformed questionnaire on the mobile phone usage, lifestyle, and its effects were obtained from all the participants and only the participants who had a usage from a minimum of 1 hour to a maximum of 10 hours per day were included in the study. All the participants were between the age group between 18 and 45 years.

The participants who used the hand-held mobile phones predominantly on one side were selected and included for the study. Individuals who were having systemic disorders, salivary gland diseases or history of previous salivary gland surgeries, history of radiation to the orofacial structures, long-term use of any drugs and those who used hands-free devices like microphones or blue-tooth devices for voice calls were excluded from the study.

Randomized sampling was done, and participants were divided into 3 groups based on the duration of mobile phone usage per day. Group A comprised of participants who used mobile phones for 0-2 hours a day, group B comprised of participants who used mobile phones for 2-4 hours a day and group C comprised of participants who used mobile phones for more than 4 hours a day. A total of 15 participants belonged to group A, 14 participants in group B and 13 participants in group C. A modified Schirmer strip was used to measure the salivary flow rates from both the dominant and non-dominant sides of usage. Parotid saliva was collected using Carlson-Crittenden device from both the dominant and non-dominant sides and the salivary pH, total protein concentrations, IgA, salivary amylase, and total antioxidant capacity were estimated.

For estimation of salivary flow rate

The sample collection was done between 8 am and 12 am and the participants were asked not to eat or drink for at least half an hour before the collection of saliva. Unstimulated parotid salivary flow rate from both the sides were measured with modified Schirmer test strips. The modified Schirmer strips (Tear touch- Madhu Instruments Pvt limited, New Delhi India) used was a 4 cm filter paper strip with millimeter calibrations that graduate from 5 to 35 mm. The wick end of the Schirmer strip was held at the opening of the Stenson's duct using a tweezer after isolation of the corresponding buccal mucosa. The salivary flow rate was expressed in millimeters for 5 minutes. The similar method was also followed on the non-dominant side and the dominant side was compared with the non-dominant side of the patients participating in the study. The unstimulated parotid saliva was collected to measure the function of the parotid gland in its normal resting state.

To estimate pH of saliva and total protein, IgA, amylase, total antioxidant capacity

The buccal mucosa was dried with gauze and the Carlson-Crittenden device was placed primarily on the dominant side of mobile phone usage and the salivary flow was stimulated using 2% citric acid. It was taken in a cotton swab and applied over the tongue and the oral part of lower lips for a total of 2 minutes. The saliva was collected in the saliva collector for 3 minutes. The sterile pH strips (Fischer Instruments, New Delhi) were taken using the tweezer and dipped into the collecting tube for duration of one minute [Figure 1]. The color change was observed and matched with the shade guide provided by the manufacturer. Again, the saliva was collected in sterilized saliva collecting glass tubes for 3 minutes and the saliva samples were stored in ice at -4 degrees Celsius. The samples were immediately transferred to the Department of Medical Biochemistry for the estimation of total protein, IgA, amylase and total antioxidant capacity of saliva.
Figure 1: Method of saliva collection using Carlson-Crittenden tube

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Protein was estimated by the method proposed by Lowry et al. (1951). Estimation of IgA was done using the kit obtained from (Krishgen biosystems). Estimation of Total Antioxidant Capacity was done using ABTS method. Amylase was quantified manually by initially preparing 4 reagents of starch, 1% sodium chloride, dinitro salicylic acid and standard solution of maltose.

Statistical analysis

The obtained data was entered on an excel spreadsheet and validated using statistical package for social sciences software (IBM SPSS Statistics for windows, version 18.0). One-way ANOVA was used to compare the salivary flow rate, salivary pH, salivary IgA level, salivary total protein, salivary total antioxidant capacity and salivary amylase level among the three groups both for dominant and non-dominant side usage. Tukey's HSD test and Pearson's correlation were done to find the nature of correlation between hours of usage of mobile phone and all the salivary parameters.


   Results Top


A total number of 40 participants were involved in the study with a mean age of 23.92 ± 7 years [Figure 2]. There were 29 (70%) males and 11 (30%) females who participated in the study.
Figure 2: Age distribution

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Among the participants, 60% complained of some discomfort in the skin surrounding the ear where the hand-held mobile phones were placed while speaking. Tingling sensation of the skin surrounding the ear region was reported by 12.5% of users and burning sensation of the skin adjacent to the region of placement of hand-held mobile phones was reported by 10% of the overall participants. About 7.5% of the participants complained of ear pain when using hand-held mobile phones for calling for longer durations and 5% complained of both ear pain and feeling of warmth over the skin surrounding the ears when placing the mobile phone during calls [Figure 3].
Figure 3: Prevalence of discomfort

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There was an increase in the mean salivary flow rate, pH and salivary IgA levels on the dominant side of participants. The mean salivary flow rate and pH in group A, B and C on the dominant sides were 11.6 ± 4.21, 10.57 ± 3.30 and 10.12 ± 2.47 and 5.87 ± 0.52, 6.7 ± 0.85 and 7.18 ± 1.17 respectively [Figure 4]. In the non-dominant side, the salivary flow rate and pH in groups A, B and C were 10.17 ± 3.95, 10.57 ± 3.30, 7.77 ± 3.86 and 5.73 ± 0.59, 6.50 ± 0.94, 6.09 ± 2.26, respectively. The results obtained for mean salivary flow rate and salivary pH in groups A, B and C between dominant and non-dominant sides were statistically non-significant.
Figure 4: Mean salivary flow rate levels in all study groups in the dominant and non-dominant sides

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The mean total protein and IgA levels in the dominant side of groups A, B, and C were 22.56 ± 9.35, 20.10 ± 4.95 and 17.44 ± 4.52 and 3.39 ± 0.62, 5.03 ± 0.72 and 7.51 ± 1.17. In the non-dominant side, the mean salivary IgA for groups A, B and C were 4.36 ± 2.02, 4.58 ± 1.177 and 5.14 ± 1.09 respectively. For groups A , B and C in the non-dominant sides of mean total protein levels, the values were 24.81 ± 12.44, 20.96 ± 8.19 and 23.27 ± 9.33 respectively [Figure 5]. The results obtained in groups A and B for salivary IgA and total protein levels between the dominant and non-dominant sides were non-significant and in group C the values were significant. (P = 0.000).
Figure 5: Mean salivary total protein levels in all study groups in the dominant and non-dominant sides

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There was a decrease in the mean amylase, total proteins and mean total antioxidant capacity in the dominant side. The mean salivary amylase levels in the dominant and non-dominant sides of groups A, B and C were 71.53 ± 4.38, 71.52 ± 5.11, 71.24 ± 5.92 and 71.61 ± 4.37, 71.94 ± 4.60 and 71.34 ± 5.84 respectively. The results obtained for salivary amylase in all three groups between dominant and non-dominant sides were statistically non-significant. The mean salivary total antioxidant capacity levels in the dominant and dominant sides of groups A, B and C were 1.04 ± 0.27, 1.008 ± 0.038, 1.012 ± 0.062 and 1.03 ± 0.08, 1.018 ± 0.029 and 1.01 ± 0.062 respectively. The results obtained for groups A and B for total antioxidant capacity between dominant and non-dominant sides were statistically significant (p = 0.0000) and the results obtained for group C was statistically non-significant [Table 1].
Table 1: Comparison of mean Salivary flow rate, pH, IgA, Total proteins, Total antioxidant capacity, Salivary amylase between dominant and non dominant sides in different study groups

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When inter group comparison was done between groups A & B, B & C and A & C for salivary pH in the dominant side, groups A & B and A & C were statistically significant. Similarly inter group comparison between all three groups for total antioxidant capacity levels were statistically significant on the dominant side. For salivary IgA, the groups B & C and A & C in the dominant sides were statistically significant. (p = 0.000) [Table 2], [Table 3], [Table 4].
Table 2: Comparison of mean salivary flow rate, pH between dominant and non dominant sides in different study group

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Table 3: Comparison of mean salivary IgA and Total antioxidant capacity between dominant and non dominant sides in different study groups

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Table 4: Comparison of mean total proteins and Salivary amylase between dominant and non dominant sides in different study groups

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   Discussion Top


The mobile phone widely used today is a wireless hand-held device that allows the users to make calls using electromagnetic radiofrequency signals. The effects of the electromagnetic radiations can be classified as thermal and non-thermal effects which can cause derangement in the various salivary constituents and the physiology of the salivary gland as a whole can be affected. Various questionnaire studies have been done to analyze the symptoms caused due to prolonged mobile phone usage. In our study, we had three groups depending upon the hours of usage of the mobile phone. A questionnaire was used to record information on the use of hand-held mobile phones and the salivary pH, total protein concentrations, immunoglobulin A (IgA), salivary amylase, total antioxidant capacity were estimated. Hand held mobile phones can generate a heat no greater than 0.1 degrees Celsius in the highest-powered models according to Van Leeuwan et al.[3] In our study 60% of participants complained of warm sensation around the ear due to prolonged usage. This heating of the biological tissue can be attributed to the absorption of microwave energy by the water content of the tissues.[4],[5] The other common complaints were tingling sensation and burning sensation of the skin surrounding the ear region [Figure 2]. The salivary flow rate is an important indicator of normal undisturbed physiology. The stimulated parotid salivary flow rate per minute is 1.0 to 2.0 ml.[6] The production of saliva involves initial water transport from the serum into the terminal portion of acinar cells that is influenced by pathways like the parasympathetic pathway which induces more watery saliva and the sympathetic pathway which secretes more protein content.[7] Our study showed variations and increase in mean salivary flow rate in the dominant side among the study groups of A, B and C similar to some studies who stated that there was an increase in the mean salivary flow rate on the dominant side of usage.[8],[9],[10]

The possible reason could be because of the heating of the biological tissue leading to modification in the cutaneous blood flow leading to an increase in the perfusion of the tissue.

One of the important functions of salivary pH is its buffering capacity. The buffering action of saliva is mainly due to the following components like bicarbonates, phosphates, urea, amphoteric proteins and enzymes. The two ions; bicarbonates and phosphates are found in increased concentrations in the parotid saliva and this buffering action works more efficiently during stimulated high flow rates.[11] In our study the mean pH in the groups A, B and C had increased on the dominant side when compared to the non-dominant side showing an alkaline shift in the pH values. Now this variation in the pH can be attributed to the increase in the secretion of bicarbonate ions which increases proportionally to the salivary flow rate.[12] In a similar study done in mobile phone users, there was no significant difference in salivary pH between heavy users of mobile phones and the control group.[13]

Saliva is filled with various protein constituents like amylase, immunoglobulin A, lactoferrin, lysozyme, mucins, peroxidase, histatins, and cystatins.[14],[15],[16] In our study, in all the study groups the total protein concentration is less on the dominant side similar to the studies done by Pattipatti et al.[17] In another study done to evaluate the effect of mobile phones on the salivary glands, the salivary flow rate and protein concentration of the parotid gland were significantly more on the dominant side than the non-dominant side of mobile phone usage.[18]

The variations and the divergent effect on fluid and protein concentration may be attributed to the various effects of mobile phones use on the parasympathetic and sympathetic pathway. Also, in a study done in 2008 there was an influence of mobile phones on heart rate variability parameters in healthy individuals showing that parasympathetic tone increased while the sympathetic tone decreased during mobile phone usage.[19]

Salivary amylase is the most abundant protein in saliva. Alpha amylase enters the oral cavity by mucosal transudation and ultra-filtration. The total number of antibodies which are transported by each route depends upon factors like gingival and mucosal inflammations and the integrity of the acinar and mucosal barriers.[20],[21] In our study since there is a decrease in the total protein concentration on the dominant side all the constituents including the amylase is seen to be less and has a variation when comparing the non-dominant side to the dominant side.

An interesting aspect about the various salivary proteins is their ability to be indicators of stress in the oral cavity. Alpha amylase and cortisol levels in saliva are well established indicators of stress according to experiments on electromagnetic frequency. Now in addition, IgA is also of major interest in connection to stress.[22] Our study had shown a decrease in the mean salivary IgA levels on the dominant side in patients who used mobile phones for less than 2 hours and an increase in the mean salivary IgA levels in the dominant side in patients who had a longer duration of more than 2 hours of usage. So, the results in our study can attribute to the various factors which cause an increase or decrease in salivary IgA levels due to the stress effects. A similar study by Khalil et al., observed no correlation between salivary IgA levels and the intensity of mobile phone usage.[23] Further studies have to be conducted to establish the exact mechanism of IgA response and variations caused by the use of hand-held mobile phones.

Saliva is an important fluid contributing as a first line of defense against free radical mediated oxidative stress. Disturbance of redox balance, uncontrolled activation of free radical processes, over production of reactive oxygen species and suppression of antioxidant defense in cell are commonly seen as some hazardous changes in cell metabolism. In the present study there is an overall compensatory decrease in the antioxidant capacity in saliva in all the study groups in the dominant side showing the associated oxidative stress related to the increase in the radiofrequency electromagnetic radiation. It can be added that even though the effect of electromagnetic radiation on living organisms depends on the frequency, intensity and duration of exposure of mobile phone radiation, it is nevertheless a serious factor contributing to damage of oral and para oral structures.[24]


   Conclusion Top


In conclusion, our study has shown an increase in the levels of salivary flow rate, pH, IgA and a decrease in the salivary amylase, total proteins and total antioxidant capacity levels on the dominant side of usage it can be concluded that the electromagnetic radiations emitted from the hand-held mobile phones and the thermal changes due to the placement of the phones near the tissues can cause continuous insult to the parotid gland leading to pathogenesis.

Along with this, the type of location where the phone is used, the power levels across different technologies, factors with respect to the base station and also, the geographic differences in radiofrequency power output levels, dose, time pattern and frequencies of exposure should all be considered in future studies.

Acknowledgements

Nil

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

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