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 Table of Contents  
ORIGINAL ARTICLE
Year : 2022  |  Volume : 34  |  Issue : 1  |  Page : 45-52

A clinical comparative study with evaluation of gustatory function among oral submucous fibrosis patients, gutka chewers, chronic smokers and healthy individuals


Oral Medicine and Radiology, Kalinga Institute of Dental Sciences, KIIT University, Bhubaneswar, Odisha, India

Date of Submission07-Oct-2021
Date of Decision27-Dec-2021
Date of Acceptance30-Jan-2022
Date of Web Publication25-Mar-2022

Correspondence Address:
Dr. Snehjyoti Jha
Kalinga Institute of Dental Sciences, KIIT University, Bhubaneswar, Odisha
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jiaomr.jiaomr_294_21

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   Abstract 


Context: Oral submucous fibrosis (OSMF) is a chronic debilitating disease with significant malignant potential. The most common symptoms of the condition include burning sensation, trismus, swallowing, and speech impairment as well as gustatory alteration. Aims: The aim of the study was to evaluate and compare the efficacy of gustatory functions in oral submucous fibrosis patients, gutka chewers, chronic smokers and healthy individuals. Methods and Material: A total of 112 individuals were selected for the study and divided into four groups of 28 participants, each comprising OSMF patients, gutka chewers, chronic smokers with gutka-chewing habits, and healthy individuals. Each participant was assessed for gustatory function using four different tastants for sweet, sour, salty, and bitter, and the taste perception was recorded as hypogeusia, hypergeusia, dysgeusia, and ageusia. Statistical Analysis Used: Data obtained were analyzed with SPSS software version 26. A comparison between the four groups was made separately for the four different tastes and the five parameters. A P value of ≤0.05 was considered statistically significant. Results: For OSMF patients, gutka chewers, and chronic smokers with gutka-chewing habits, salty taste showed normal perception, sweet taste showed hypogeusia, and bitter taste reported ageusia. The healthy individuals mostly showed normal perception for almost all tastes. Conclusions: It can be concluded that OSMF and habitual consumption of areca nut and tobacco appear to have a significant impact on the alteration of the gustatory function, although the type of taste sensation that is affected may vary from person to person.

Keywords: Gustation, gutka chewers, oral submucous fibrosis, taste alteration


How to cite this article:
Jha S, Sangamesh N C, Bhuvaneshwari S, Mishra S, Bajoria AA, Sikdar A. A clinical comparative study with evaluation of gustatory function among oral submucous fibrosis patients, gutka chewers, chronic smokers and healthy individuals. J Indian Acad Oral Med Radiol 2022;34:45-52

How to cite this URL:
Jha S, Sangamesh N C, Bhuvaneshwari S, Mishra S, Bajoria AA, Sikdar A. A clinical comparative study with evaluation of gustatory function among oral submucous fibrosis patients, gutka chewers, chronic smokers and healthy individuals. J Indian Acad Oral Med Radiol [serial online] 2022 [cited 2022 May 27];34:45-52. Available from: https://www.jiaomr.in/text.asp?2022/34/1/45/340759




   Introduction Top


Oral submucous fibrosis (OSMF) is a chronic debilitating disease that is progressive in nature and has significant malignant potential. The disease mainly involves the lamina propria and may later go on to involve the deeper tissues of the submucosa in its advanced stages, eventually leading to loss of its fibro-elasticity.[1]

This entity was first described in 600 B.C. by Sushruta by the name “Vidari.”[2] The disease was noted by Schwartz in 1952 in five Indian females residing in Kenya. He was the one who coined the term Atrophia idiopathica (trophica) mucosae oris.[3]

However, the true understanding of the condition came several decades later when a Danish pathologist, Jens Pindborg, studied the disease in his extensive travel expeditions and very comprehensively laid out the numerous facets of the disease.[3]

The disease presents with symptoms like inability to open mouth, burning sensation, difficulty in swallowing, and speech impairment. However, a very important and most often overlooked symptom is the alteration in taste perception.[2] The causative factor areca nut is supposedly a very important reason for this. One of its major ingredients, arecoline, is said to have a parasympathomimetic effect, and gradually, the leaching of the chemical contents of the areca nut into the deeper layers of the oral mucosa leads to the alteration in taste and salivary parameters.[2]

In the past, various studies have been conducted for the evaluation of taste perception in the patients affected with OSMF. Various testing parameters have been applied, such as spatial testing, whole mouth rinse tests, salivary flow rates, salivary pH analyses, and taste perception determination using taste strips.[2]

This study was conducted with the view that in OSMF there is a significant alteration in taste perception when compared to those in habitual and healthy individuals.

The aim of the study was to evaluate and compare the efficacy of gustatory functions in oral submucous fibrosis patients, gutka chewers, chronic smokers, and healthy individuals.


   Subjects and Methods Top


A case–control study involving 112 patients was conducted in the Department of Oral Medicine and Radiology. Written informed consent was taken from each individual, and the subjects were included only with voluntary participation.

The principles of the Helsinki Declaration were followed. The study was approved by the Institutional Ethics Committee (Letter no. KIIT/KIMS/IEC/194/2019 dated 08.11.2019).

Method of collection of data (including sampling procedure, if any)

Sample size determination:

Type: Empirical data used.

Comparisons of the mean difference between the different groups were taken into consideration.

Level of significance = 5%, power = 80%, type of test = two-sided.

The formula for calculating the sample size is



Where,

n = sample size required in each group,

r = correlation coefficient between the groups = 0.3604 (data from previous studies)

d = expected mean difference between the groups = 7.3 (data from previous studies)

SD = standard deviation

Zα/2: This depends on the level of significance, for 5% this is 1.96

Zβ: This depends on power, for 80% this is 0.84

Based on the above formula, the sample size required per group is 28.

Hence, the total sample size required was 112.

The participants were accordingly divided into four groups:

Group A: 28 patients with clinically diagnosed OSMF;

Group B: 28 gutka chewers without OSMF;

Group C: 28 gutka chewers and chronic smokers without OSMF;

Group D: 28 healthy patients with no habits of gutka chewing or smoking.

Inclusion and exclusion criteria

Inclusion criteria:

  1. Individuals with clinically diagnosed oral submucous fibrosis (Stage II; according to Haider et al.[4]).
  2. Individuals with chronic gutka-chewing habits and non-smokers.
  3. Individuals with chronic gutka-chewing habits and chronic smokers.
  4. Healthy individuals with no habits of gutka chewing or smoking.


Exclusion criteria:

  1. Patients with clinical findings of other red and white lesions.
  2. Patients suffering from systemic diseases and patients on immunosuppressive drugs.
  3. Patients with severely reduced mouth opening.
  4. Patients suffering from any syndromes or mentally retarded patients.
  5. Pregnancy and lactation.
  6. Medication related to other taste disorders.
  7. Individuals with pre-diagnosed chemosensory disturbances.


The procedure involved including materials/armamentarium used:

Informed consent of the participants was taken.

Case history and oral examination—Recording of the detailed case history of the patient and oral examination using diagnostic instruments (mouth mirror and probe) were performed [Figure 1].
Figure 1: Armamentarium

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A clinical diagnosis of oral submucous fibrosis was made. The patients were not advised for histopathological evaluation since in OSMF patients any surgical intervention would further aggravate the scarring or fibrosis.

The patients were assessed for gustatory function using four different tastants. For three tastes (sweet, salty, and sour), filter paper dipped in solutions freshly prepared for these tastes was used, and for bitter taste pre-formed taste strips of phenylthiourea (PTC) were used. The filter papers and the taste strips were applied directly on the dorsum of the tongue, for approximately 5 s. The patients were asked to rinse their mouths thoroughly with water before proceeding to the next tastant. The rinsing was repeated till the patient had any lingering taste effect [Figure 2].
Figure 2: Graphical representation of the distribution of participants in various groups

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The solutions that were used for assessment are as follows:[2]

Sucrose solution (1M) for sweet taste;

Sodium chloride (1M) for salty taste;

Citric acid (32 mM) for sour taste.

The tastes perceived by the individuals were recorded as hypogeusia, hypergeusia, dysgeusia, and ageusia according to the technique described by NHANES, 2013[5] and Stillman et al., 2003[6] According to this protocol, the individuals were asked whether or not they perceived any taste, and if yes, which particular taste could they identify and accordingly their subjective response was recorded.

Statistical analysis

Data obtained were analyzed with SPSS software version 26. The findings of various parameters were evaluated and analyzed statistically using Tukey's HSD tests and Mann–Whitney U test. A comparison between the four groups was made separately for the four different tastes and the five parameters. A P value of ≤ 0.05 was considered statistically significant.


   Results Top


Sample distribution

In the present study, a total of 112 individuals were selected and divided into four groups of 28 participants each.

Demographic characteristics

The participants in the present study were in the age range varying from 16 to 59 years. Patients in the OSMF group were in the age-group of 19–56 years, those in the gutka-chewing group were in the age-group of 19–59 years, those in the gutka-chewing and smoking group were in the age-group of 22–56 years, and healthy individuals were in the age-group of 16–58 years.

The distribution of gender varied in each group [Table 1]. The majority of the participants in the present study were males (93.75%). In each group, there was a remarkable male predominance. In the OSMF group and healthy group, there were 92.9% males and 7.1% females. In the gutka-chewing group, there were 89.3% males and 10.7% females. In the combined smoking and gutka-chewing group, the entire population was male (100%).
Table 1: Demographic characteristics of the study population

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Group-wise distribution of the taste sensations

The distribution of taste sensation and type of tastes for the OSMF group is mentioned in [Table 2]. For the OSMF group, normal perception of salty taste was the highest (25%), followed by sour taste (14.3%), bitter taste (7.1%), and sweet (0). Hypogeusia was highest in sweet taste perception (60.7%). Hypergeusia was observed in only 7.1% of sour taste perception. Dysgeusia was seen in 17.9% of the sour taste perception. For bitter taste perception, ageusia was reported the highest (46.4%). The difference between varied taste sensations was statistically significant for each taste type: sweet (P = 0.002), sour (P = 0.011), salty (P = 0.006), and bitter (P = 0.002).
Table 2: Taste sensation distribution for the OSMF group

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The distribution of taste sensation and type of tastes for the gutka-chewing group is mentioned in [Table 3]. It was seen that most of the population had a normal perception of salty taste (42.9%), followed by sweet taste (39.3%), bitter taste (35.7%), and sour taste (32.1%). Hypogeusia was reported maximum for the sweet taste (53.6%). Hypergeusia was reported maximum in the sour group (42.9%). Dysgeusia was reported maximum for the sweet taste type (7.1%). The bitter sensation type reported the highest ageusia (57.1%). The difference between varied taste sensations was statistically significant for each taste type: sweet (P = 0.009), sour (P = 0.024), salty (P = 0.001), and bitter (P = 0.005).
Table 3: Taste sensation distribution for the gutka group

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The distribution of taste sensation and type of tastes for the gutka-chewing and smoking group is mentioned in [Table 4]. It was seen that most of the population had a normal perception of salty taste (42.9%), followed by bitter taste (28.6%), sweet taste (25%), and sour taste (21.4%). Hypogeusia was reported maximum for the sweet taste (64.3%). Hypergeusia was reported maximum in the sour group (53.6%). Dysgeusia was reported maximum for the sweet taste type (10.7%). The bitter sensation type reported thehighest ageusia (67.9%). The difference between varied taste sensations was statistically significant for each taste type: sweet (P = 0.002), sour (P = 0.002), salty (P = 0.001), and bitter (P < 0.0001).
Table 4: Taste sensation distribution for the gutka + smoking group

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The distribution of taste sensation and type of tastes for healthy individuals is mentioned in [Table 5]. The majority of the population belonged to the normal sensation of the taste categories with the highest in the salty category (92.9%), followed by sour taste (85.7%), sweet taste (82.1%), and bitter taste (71.4%). Hypogeusia was reported maximum for the bitter taste (25.0%). Hypergeusia and dysgeusia were not reported in the healthy group. Ageusia was reported only 3.6% in both sweet and bitter taste categories. The difference between varied taste sensations was statistically significant for each taste type: sweet (P < 0.0001), sour (P < 0.0001), salty (P < 0.0001), and bitter (P < 0.0001).
Table 5: Taste sensation distribution for the control group

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Comparison of the groups based on individual taste type

A statistically significant difference (P <.0001) of sweet taste was noted when a comparison was made between the OSMF group and other groups including gutka, gutka and smoking, and healthy individuals, as given in [Table 6]. A comparison between the OSMF group and other groups showed a significant difference (P <.0001) for sour taste sensation, as given in [Table 7]. Salty taste sensation differed significantly when the OSMF group was compared with other groups, as given in [Table 8]. A statistically significant difference (P < 0001) of bitter taste was noted when a comparison was made between the OSMF group and the other groups, as given in [Table 9].
Table 6: Comparison of the groups for the sweet taste category

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Table 7: Comparison of the groups for the sour taste category

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Table 8: Comparison of the groups for the salty taste category

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Table 9: Comparison of the groups for the bitter taste category

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   Discussion Top


Oral submucous fibrosis (OSMF) has been the topic of research for a long time now, and investigators have evaluated almost all aspects of the disease. The various manifestations of the disease, such as burning sensation, trismus, blanching, and restricted mouth opening, have been compared and analyzed time and again in various studies. However, alteration in gustatory functions, although less addressed, is also of utmost importance.

Gustatory alteration can be a serious problem if left unattended. It can be very distressing to the patients. In OSMF, in addition to the burning sensation, limited mouth opening and difficulty in swallowing, partial or complete loss of taste sensation, or alteration in taste perception poses an additional discomfort to the patient.

There are pieces of evidence in the literature suggesting the role of areca nut chewing and smoking in the taste impairment mechanism.[7–10] Areca nut consists of several chemicals and metallic ions such as copper and iron, which, on chewing, leach out into the saliva, thereby altering the composition and properties of saliva.[11]

In our study, the gustatory function was compared among four groups comprising OSMF, gutka chewers, and smokers against healthy individuals. In the present study, the OSMF patients were in the age range of 19 to 56 years, with a mean age of 33.82 ± 9.16, gutka chewers were in the age range of 19 to 59 years, with a mean age of 35.21 ± 9.13, gutka-chewing and smoking group were in the age range of 22 to 56 years, with a mean age of 34.43 ± 8.50, and the healthy individuals were in the age range of 16 to 58 years, with a mean age of 37.79 ± 11.17, which was in close accordance with the study conducted by Lalfamkima et al.[12] and Tamgadge et al.[13] The mean age was lower in studies conducted by Bangi et al.,[1] Deeplaxmi et al.,[2] and Yadav et al.[14]

In the present study, the distribution of gender varied in each group. For the OSMF group and healthy group, there were 92.9% males and 7.1% females. For the gutka-chewing group, there were 89.3% males and 10.7% females. For the combined smoking and gutka-chewing group, the entire population was male (100%). In the present study, there was a noteworthy male predilection. The results were consistent with other studies conducted by Dyasanoor et al.,[11] Yadav et al.,[14] Tamgadge et al.,[13] and Lalfamkima et al.[12] All of these studies showed a predominant male predilection. The male predominance, in this case, may be owing to the fact that areca nut-chewing habit is more prevalent in males than in females.

In the OSMF group, for the sweet, sour, and salty tastes, maximum participants showed hypogeusia (60.7%, 46.4%, and 50.0%, respectively). For bitter taste perception, ageusia was reported the highest (46.4%). Overall, all four tastes showed varied perceptions in the OSMF group. This result was in accordance with the study conducted by Yadav et al.[14] and Abdul Khader et al.[15] Also, in another study conducted by Deeplaxmi et al.,[2] they observed a delayed perception in all four tastes. On the contrary, the results obtained in the study conducted by Bangi et al.[1] showed delayed perception to sour, salty and sweet. However, in each group maximum number of participants showed a normal perception of all the tastes. According to the study conducted by Dyasanoor et al.,[11] there was a normal perception to sweet and bitter taste, hypogeusia to salty taste, and dysgeusia to sour taste. In another study conducted by Gupta et al.,[16] there was no significant difference between the taste perception in the OSMF and the control group.

In the gutka-chewing group, maximum participants showed hypogeusia for sweet and salty tastes (53.6% and 46.4%, respectively). For the sour taste, maximum individuals showed hypergeusia (42.9%). The bitter sensation type reported the highest ageusia (57.1%). In this group, all the taste perceptions were observed to have been altered in the majority of the participants. In the study conducted by Kale et al.,[17] there was a significant fall in the perception of the salty taste, which was in accordance with the results of the present study. In another study conducted by Bangi et al.,[1] the participants showed hypogeusia to sour taste, for bitter taste few participants showed hypergeusia, whereas a few others showed hypogeusia, and the rest of the participants showed normal taste perception. Their results were inconsistent with the findings of the present study.

In the group of participants with smoking habits, maximum participants showed hypogeusia for both sweet and salty tastes (64.3% and 46.4%, respectively). For the sour taste, maximum individuals reported hypergeusia (53.6%), and ageusia was reported maximum for the bitter taste (67.9%). In a study conducted by Chéruel et al.,[9] they observed that smoking significantly reduced the taste perception for all tastes, which was partly in accordance with the results of the present study. Vennemann et al.[18] conducted a study to assess the association between smoking and smell and taste impairment; the results were in accordance with the present study and show taste impairment in heavy smokers. In the study conducted by Chao et al.,[19] the results show increased taste sensitivity for the bitter taste in smokers compared to non-smokers, which is in accordance with the present study. In the study conducted by Redington et al.,[20] the results did not show any significant difference between the taste perceptions of smokers and non-smokers; thus, they were not consistent with the results of the present study.

The differences in the results obtained in the present study in comparison with the available literature may be owing to the difference in the study population, the ethnic diversity of the study groups, geographic distribution, genetic predisposition of the participants, and sample size.


   Limitations and Future Scope of Study Top


The present study has been conducted for evaluating the gustatory perception in OSMF patients and chronic tobacco users (both smokeless and smoked form) compared to healthy individuals. However, within the scope of this study, there were a few limitations. The sample size taken for the study could have been larger, and there was limited literature on the effects of smoking and gutka chewing combined on taste perception. Future studies can be conducted on the combined effects of smoking as well as gutka chewing on the gustatory alterations.


   Conclusion Top


After all the evaluation and the relative comparisons with other relevant studies, it can be concluded that gustation is a fairly important parameter to be assessed in the clinical manifestation of OSMF. The incidence of OSMF, according to this study, was found to be maximum in the fourth decade and predominantly in males, owing to the habit of areca nut chewing. OSMF and habitual consumption of areca nut and tobacco appear to have a significant impact on the alteration of the gustatory function, although the type of taste sensation that is affected may vary from person to person. It is imperative that we recognize this problem and address it accordingly, to improve the patient's quality of life.

Further studies are essential to include the stages of OSMF (early, moderate, and advanced) and to estimate the exact stage at which the taste sensation is altered. Thereby, a gustatory threshold can be used as an adjunct early diagnostic tool.

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.

Key messages

Gustatory evaluation in OSMF patients and tobacco users, although quite important, is a rarely acknowledged attribute. Alterations in taste perception are a significant symptom as any other disabilities of the disease and should be treated similarly. This study primarily focuses on the evaluation of the taste perception in OSMF patients and tobacco users compared to healthy individuals.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
   References Top

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Bangi BB, Ginjupally U, Nadendla LK, Mekala R, B JL, Kakumani A. Evaluation of gustatory function in oral submucous fibrosis patients and gutka chewers. Asian Pacific J Cancer Prev 2019;20:569–73.  Back to cited text no. 1
    
2.
Deeplaxmi R, Sakarde SB, Sur J, Singh AP, Jain S, Mujoo S. Altered taste perception in oral submucous fibrosis: A research. J Indian Acad Oral Med Radiol 2012;24:288–91.  Back to cited text no. 2
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Tilakaratne WM, Ekanayaka RP, Warnakulasuriya S. Oral submucous fibrosis: A historical perspective and a review on aetiology and pathogenesis. Oral Surg Oral Med Oral Pathol Oral Radiol 2016;122:178–91.  Back to cited text no. 3
    
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Haider SM, Merchant AT, Fikree FF, Rahbar MH. Clinical and functional staging of oral submucous fibrosis. Br J Oral Maxillofac Surg 2000;38:12–5.  Back to cited text no. 4
    
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Tamgadge P, Wasekar R, Kulkarni S, Chandran A, Jain S, Chalapathi KV, et al. Comparative evaluation of alteration in salivary pH among gutkha chewers with and without oral submucous fibrosis and healthy subjects: A prospective case-control study. J Curr Oncol 2020;3:8–16.  Back to cited text no. 13
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    Figures

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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9]



 

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