World Rural Health Conference
Home Print this page Email this page Small font size Default font size Increase font size
Users Online: 357
Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 


 
 Table of Contents 
ORIGINAL ARTICLE
Year : 2019  |  Volume : 8  |  Issue : 8  |  Page : 2587-2591  

Comparison of salivary epidermal growth factor in patients with recurrent aphthous stomatitis, smokers, and healthy individuals


1 Department of Oral Medicine, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran
2 Department of Oral and Maxillofacial Surgery, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran

Date of Submission15-Feb-2019
Date of Decision25-May-2019
Date of Acceptance06-Jun-2019
Date of Web Publication28-Aug-2019

Correspondence Address:
Dr. Farzad Rezaei
Assistant Professor, Department of Oral and Maxillofacial Surgery, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah
Iran
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jfmpc.jfmpc_397_19

Rights and Permissions
  Abstract 


Background: Recurrent aphthous stomatitis (RAS) is one of the most common oral ulcerative diseases with unknown etiology. Epidermal growth factor (EGF) has been suggested to play a similar role in RAS. Therefore, this study investigated the salivary EGF level in patients with RAS, the patients without RAS, and smokers. Materials and Methods: A total of 91 samples were recruited in this case-control study: 30 RAS patients, 30 controls, and 31 smokers. Age and gender were matched in the groups. In the case group, the salivary sample was taken during the infection and remission periods. Salivary EGF concentration was measured by Crystal Dibiotic assay (made in China) using ELISA technique. Finally, the data were analyzed by SPSS software (Version 18.0, Inc., Chicago, IL, USA). Results: The results of paired t-test showed no statistically significant difference in salivary EGF between the infection and remission periods (P = 0.987). ANOVA test showed a statistically significant difference in EGF between the study groups (P < 0.001), as the mean salivary EGF was significantly lower in the smokers than the case and control groups during the infection and remission periods. Conclusion: The present study showed a lower level of salivary EGF in the smokers without a history of RAS. There was no statistically significant difference between the infection and remission periods in salivary EGF in the patients with RAS. Furthermore, salivary EGF showed no statistically significant difference between the patients with RAS and the controls.

Keywords: Epidermal growth factor, recurrent aphthous stomatitis, saliva, smoking


How to cite this article:
Rezaei F, Hosseini E, Rezaei F. Comparison of salivary epidermal growth factor in patients with recurrent aphthous stomatitis, smokers, and healthy individuals. J Family Med Prim Care 2019;8:2587-91

How to cite this URL:
Rezaei F, Hosseini E, Rezaei F. Comparison of salivary epidermal growth factor in patients with recurrent aphthous stomatitis, smokers, and healthy individuals. J Family Med Prim Care [serial online] 2019 [cited 2019 Sep 15];8:2587-91. Available from: http://www.jfmpc.com/text.asp?2019/8/8/2587/265581




  Introduction Top


Recurrent aphthous stomatitis (RAS) is the most prevalent cause of the painful oral ulcer. RAS affects approximately 20% of general population. RAS is characterized by recurrent ulcers. Each lesion lasts about 1–2 weeks and is typically multiple, small, round, or oval with a defined margin, a red halo, and a yellow or gray background.[1] RAS is classified to minor ulcer (less than diameter), major ulcer (over 1 cm), and herpetiform ulcers.

RAS is a multifactorial illness with unknown etiology.[2] Genetics, nonregulation of immune system, malnutrition, stress, topical trauma, hormonal disorders, infection, oral health, weak anemia due to iron deficiency, folic acid and deficient absorption of B12 vitamin, periodic neutropenia, and celiac disease have been proposed as the factors affecting the incidence of this disease in specific subgroups of people.[3] Recently, free radicals have been suggested to be involved in the etiology of this illness by inducing oxidative stress.[4] When oxygen-free radicals are produced beyond their physiologic limit, or when the antioxidant defense mechanism of the body is reduced, oxidative stress occurs, which can be a life-threatening issue and can lead to histological damage in some cases.[5] Some studies have supported the effect of smoking on the reduced incidence of aphthous lesions but the reason of that is not clear.[6]

Salivary epidermal growth factor (EGF) plays a pivotal role in maintaining the oral health and ameliorating the oral ulcers. Saliva plays a key role in the oral health so that it can preserve the integrity of the oral mucosal membrane through liquefaction and amelioration of the soft tissue.[7] EGF is a single polypeptide with 53 amino acids.[8] Numerous growth factors such as EGF, insulin-like growth factor (IGF), neural growth factor (NGF) and transforming growth factor (TGF) synthesis are secreted through saliva, the most important of which is EGF. Salivary EGF induces the mitotic response of the cell, thereby playing a role in the activation of RNA and synthesis of DNA, protein, and extracellular macromolecules.[8]

As for the effect of EGF on aphthous ulcers, it is assumed that salivary growth factors such as EGF play a key role in maintaining the oral health, healing the oral ulcers, and preserving the oral mucosa health.[9] Considering the efficacy of salivary EGF in maintaining oral health and healing oral ulcers, the researchers in this study made an attempt to determine whether salivary EGF level is different in the infection and remission periods and whether it is different in the healthy people and patients. Also, since aphthous has been reported to reduce in the smokers, we made an effort to see whether smoking affected salivary EGF or not.


  Materials and Methods Top


A total of 91 samples, including 30 participants without RAS, 30 patients with minor RAS (less than 1-cm lesion) and 30 smokers without RAS (smoking at least six cigarettes daily and a history of six months) were recruited in this case-control study. They were selected by a convenience sampling method. The indices required for sample size estimation were taken from the study of Wang et al.[10] as follows:

μ1=0.58, μ2 = 0.52, S1 = 0.07, S2 = 0.07.

The following formula was used to calculate the sample size. Furthermore, the confidence level of 95% and test power of 90% were taken into account.



Sample size calculation was performed by PASS software (Version 11).

In this case-control study, salivary EGF was compared between the study groups. The first group included healthy individuals (control group), the second group comprised of the patients with minor RAS (case group), and the third group consisted of the smokers (control group for RAS). The second group was evaluated in the infection period and almost ten days after. After taking written informed consent from the participants, they were included in the study. All the consent forms were approved by the ethics committee of the Kermanshah University of Medical Sciences. As stated in the consent forms, participation or nonparticipation in this study was voluntary and had no effect on the treatment process.

The inclusion criteria in this study were as follows:

  1. Patients with RAS (with a minimum history of thrice a year in the case group);
  2. Patients with RAS after improvement of the lesion;
  3. People with no history of RAS in the control group; and
  4. Smokers (at least six cigarettes a day for six months) with no history of oral aphthous.


The exclusion criteria in this study comprised of the following:

  1. History of systemic diseases and pregnant women;
  2. Periodontal diseases;
  3. History of any drug consumption in the past three months;
  4. Presence of any oral pathologic lesion;
  5. Smoking less than the amount determined in this study; and
  6. The case and control groups being matched in terms of age, gender, and oral health.


After washing their mouth for 2 min to decrease bacterial contamination, saliva samples (5 cc) were collected from all participants by spitting during 10:00–12:00 am when the samples had not drunk or eaten anything 2 h before saliva collection.[11] All samples were kept at -20°C for analysis. The samples were then centrifuged with 100 cc diluted phosphate buffered saline at 400 g for 5 min. Salivary EGF concentration was measured by Crystal Dibiotic assay (made in China) by the ELISA method.[8]

To collect the data, first, the consent forms were approved by the ethics committee of the Kermanshah University of Medical Sciences (no: IR.KUMS.REC.1396.382). As shown in the consent forms, participation in the study was completely voluntary and had no effect on the treatment process. After homogenization, the two groups were tested.

Data analysis was done through descriptive and inferential statistics. For descriptive statistics, central tendency and dispersion parameters along with tables and graphs were reported. For inferential statistics, the normality of data was analyzed by the Kolmogorov–Smirnov test. Given the normality of data, the t-test was used to compare the salivary EGF between the infection and remission periods, and the ANOVA test was run for multiple comparisons between groups. Moreover, the Tukey post-hoc test was used for the pair comparison. Data were analyzed by SPSS software (Version 18.0, Inc., Chicago, IL, USA). P < 0.5 was considered significant.

As for ethical considerations, written consent was taken from all participants. They could withdraw from the study at any stage they wished. No risk threatened the patients.

The limitations of this study included patient cooperation (they were motivated to take part in the study) and small sample size (a limited time was set to complete the samples).


  Results Top


A total of 91 participants were included in this study: 30 patients with RAS, 31 smokers, and 30 healthy controls.

The results of the Kolmogorov–Smirnov test showed the data followed a normal distribution pattern (P > 0.1) [Table 1].
Table 1: Results of Kolmogorov-Smirnov for the normality of data

Click here to view


The findings of the paired t-test indicated no statistically significant difference between the infection and remission periods in salivary EGF [Table 2].
Table 2: Mean and standard deviation of salivary EGF in the infection and remission periods along with their pair comparison

Click here to view


The results of ANOVA test showed a statistically significant difference in salivary EGF among the study groups (P < 0.001) as the mean salivary EGF was significantly lower in the smokers than the control and infection groups [Table 3].
Table 3: Mean and standard deviation of salivary EGF in the smokers and infection and control groups

Click here to view


The results of ANOVA test indicated a statistically significant difference among the study groups in salivary EGF (P < 0.001) as mean salivary EGF was significantly lower in the smokers than control and remission groups [Table 4].
Table 4: Mean and standard deviation of salivary EGF in the smokers and infection (after remission) and control groups

Click here to view



  Discussion Top


Bacterial infection, immunologic disorders, and increased viscosity of the submucosal extracellular matrix are factors that affect the incidence of RAS. Furthermore, various studies have reported psychological factors, hormonal changes, trauma, dietary sensitivity and allergy, blood disorders, and nutritional deficiency as the risk factors of aphthous. In fact, RAS is a cellular immune response in which T lymphocytes, cytokines, and tumor necrosis cause epithelial cell death and ulcer.[12],[13] Natural healing of ulcers and oral lesions is the result of a complex interaction among various types of cells at the ulcer area and their ability in producing a series of growth factors and responses. These factors regulate growth, cell migration and proliferation, extracellular matrix production, enzymatic activity, and higher growth factor production. Therefore, it is believed that the growth factors, which have a topical function, partly regulate the remission process.[14],[15]

Considering this issue, the present study investigated the salivary EGF in the healthy people, patients with RAS, and smokers in order to shed more light on the effect of this topical growth factor on the prevention or rapid improvement of the ulcer as well as the lesions caused by RAS. Kim et al. reported that EGF increased the production of protein and RNA in the epidermal cells.[16] Jiang et al. also indicated the role of EGF in the restoration of corneal injuries and gastric ulcer and stated that this factor inhibited the proliferation of gastric cancer cells.[17] Moreover, Hashimoto et al. reported that this factor had a mitogenic effect and increased the proliferation of keratinocyte, fibroblast, and epithelial cellsin vitro and in vivo.[18]

In a clinical study titled “diabetes mellitus type 2 and prevalence of endodontic and periodontic diseases” in a Brazilian population, Marrotta recruited 30 patients with type-2 diabetes and 60 nondiabetic samples. They reported that salivary EGF played a critical role in improving the complications of oral lesions and periodontal disease, oral infections, enlargement of salivary glands, and dry mouth.[19],[20],[21],[22] In a study on the salivary EGF in Behcet's disease and RAS, Adisen et al. stated that salivary EGF protected the patients against injuries and helped to maintain the integrity of the digestive system mucosa. Their results showed Behcet's disease and RAS reduced the salivary EGF level even in the absence of oral ulcer.[15]

Gu et al. evaluated the salivary EGF concentration changes in the patients with RAS. They recruited 33 healthy controls and 27 patients with RAS and homogenized them in terms of age and gender. In the case group, the saliva samples were taken in the infection and remission periods. Their findings showed EGF concentration was lower in the case group than the control group, indicating a significant difference between them. However, there was no statistically significant difference between the infection and remission periods in EGF concentration in the case group.[19] In the present study, the paired t-test showed a statistically significant difference between the infection and remission periods in the salivary EGF. Hence, it seems that salivary EGF remains constant in these people, which may be a reason for the periodic recurrence of RAS in these patients. Also, improvement occurs only normally, and lesion recurrence is possible in the case of intensification of any etiologic factors. Furthermore, there is no inherent mechanism in the oral cavity and saliva to prevent or improve these lesions rapidly.

In a case-control study, Brozovic et al. investigated vascular endothelial growth factor (VEGF) in the patients with minor and major aphthous (case group) and individuals with no history of RAS (control group). The study sample included 27 controls and 30 patients who were homogenized with regard to age and gender. The results indicated a statistically significant difference between the two groups in VEGF; the lower was the VEGF level, the higher was the RAS.[20] Girdler et al. assessed the effects of EGF mouthwash on the cytotoxicity induced by oral aphthous. They evaluated the effect of this mouthwash on the improvement and initiation of oral ulcer in 12 patients under cancer chemotherapy. They found no significant difference between the controls and patients in the speed of ulcer healing but reported a small delay in the initiation and severity of the ulcer.[21]

Wung et al. investigated the salivary EGF in the patients with RAS and controls and reported EGF as a very important cell support in the saliva. They classified the progress of RAS into three stages, including proactive stage (red mucosa), active stage (mucosal ulcer), and remission stage. Their results showed salivary EGF reduced significantly in the active stage of ulcer in comparison with the control group. In general, they reported a significant association between the salivary EGF and improvement of the ulcer induced by RAS.[10]

On the other hand, various studies have pointed out that smoking decreases the incidence of RAS. Quitting smoking has been reported as a factor accelerating aphthous in some patients.[23],[24] In an epidemiologic study, all the tobacco smokers showed a lower incidence of RAS than nonsmokers. In this study, tobacco increased mucosal keratinization, which in turn caused the mucosa to be less prone to developing the ulcer. Tobacco reuse after a nonuse period improved the preexisting ulcers during few days.[24]

The findings of the present study showed a statistically significant difference among the study groups in salivary EGF; as salivary EGF was significantly lower in the smokers than the control and infection groups. Moreover, mean salivary EGF was significantly lower in the smokers than the control and remission groups.


  Conclusion Top


The results of the current study indicated no statistically significant difference between the infection and remission periods in the salivary EGF in the patients with RAS. Furthermore, there was no statistically significant difference between the controls and patients with RAS in the salivary EGF. Moreover, salivary EGF concentration was significantly lower in the smokers without aphthous than the control and case groups. Some studies have shown that smoking reduces the risk of RAS. On the other hand, epidermal growth has an effective topical impact on the restoration and prevention of various lesions and ulcers. Hence, it was hypothesized that increased EGF would be an intermediate ring for the effect of smoking on the reduction of RAS, which was rejected based on the results obtained in this study. Furthermore, smoking did not increase the EGF but reduced the concentration of this factor. Accordingly, future studies are suggested to evaluate the role of other growth factors, cytokines, inflammatory factors, etc., in the patients with RAS (during infection and remission periods), healthy people, and controls to shed more light on all dimensions of this illness.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Griffiths C, Barker J, Bleiker T, Chalmers R, Creamer D. Rook's Textbook of Dermatology. Hoboken, NJ: Wiley-Blackwell; 2016.  Back to cited text no. 1
    
2.
Rezaei F, Soltani T. Evaluation and comparison of total antioxidant capacity of saliva between patients with recurrent aphthous stomatitis and healthy subjects. Open Dent J 2018;12:303-9.  Back to cited text no. 2
    
3.
Koybasi S, Parlak AH, Serin E, Yilmaz F, Serin D. Recurrent aphthous stomatitis: Investigation of possible etiologic factors. Am J Otolaryngol 2006;27:229-32.  Back to cited text no. 3
    
4.
Gurel A, Altinyazar H, Unalacak M, Armutcu F, Koca R. Purine catabolic enzymes and nitric oxide in patients with recurrent aphthous ulceration. Oral Dis 2007;13:570-4.  Back to cited text no. 4
    
5.
Rahmani M, Ghoorchi V, Rezaei F, Vaisi-Raygani A. Evaluation of total antioxidant capacity of saliva in high school students. Glob J Health Sci 2015;8:89-94.  Back to cited text no. 5
    
6.
Marakoǧlu K, Sezer RE, Toker HÇ, Marakoǧlu İ. The recurrent aphthous stomatitis frequency in the smoking cessation people. Clin Oral Investig 2007;11:149-53.  Back to cited text no. 6
    
7.
Carpenter G, Cohen S. Epidermal growth factor. J Biol Chem 1990;265:7709-12.  Back to cited text no. 7
    
8.
Abdolsamadi HR, Rezaei F, Goodarzi MT, Moghimbeigi A, Jazaeri M, Asadi S, et al. Comparison of salivary nitric oxide and epidermal growth factor level between diabetic patients and healthy individuals. Int J Diabetes Dev Ctries 2015;35:477-82.  Back to cited text no. 8
    
9.
Ramezani F, Maleki Z, Mortazavi H, Sabour S, Yadegari Z, Baharvand M. Salivary level of epidermal growth factor in recurrent aphthous stomatitis. Dent Med Probl 2015;52:33-8.  Back to cited text no. 9
    
10.
Wu-Wang C, Patel M, Feng J, Milles M, Wang S. Decreased levels of salivary prostaglandin E2 and epidermal growth factor in recurrent aphthous stomatitis. Arch Oral Biol 1995;40:1093-8.  Back to cited text no. 10
    
11.
Eivazi M, Falahi N, Eivazi N, Eivazi MA, Vaisi Raygani A, Rezaei F. The effect of scaling and root planning on salivary TNF-α and IL-1α concentrations in patients with chronic periodontitis. Open Dent J 2017;11:573-80.  Back to cited text no. 11
    
12.
Rezaei F, Aminian M, Raygani AV. Evaluation of salivary cortisol changes and psychological profiles in patients with recurrent aphthous stomatitis. Contemp Clin Dent 2017;8:259-63.  Back to cited text no. 12
[PUBMED]  [Full text]  
13.
Ship JA, Chavez EM, Doerr PA, Henson BS, Sarmadi M. Recurrent aphthous stomatitis. Quintessence Int 2000;31:23-7.  Back to cited text no. 13
    
14.
Konturek S, Dembinski A, Warzecha Z, Bielanski W, Brzozowski T, Drozdowicz D. Epidermal growth factor (EGF) in the gastroprotective and ulcer healing actions of colloidal bismuth subcitrate (De-Nol) in rats. Gut 1988;29:894-902.  Back to cited text no. 14
    
15.
Adışen E, Aral A, Aybay C, Gürer MA. Salivary epidermal growth factor levels in Behçet's disease and recurrent aphthous stomatitis. Dermatology 2008;217:235-40.  Back to cited text no. 15
    
16.
Kim H, Muller WJ. The role of the epidermal growth factor receptor family in mammary tumorigenesis and metastasis. Exp Cell Res 1999;253:78-87.  Back to cited text no. 16
    
17.
Jiang G, Hunter T. Receptor signaling: When dimerization is not enough. Curr Biol 1999;9:568-71.  Back to cited text no. 17
    
18.
Hashimoto K, Higashiyama S, Asada H, Hashimura E, Kobayashi T, Sudo K, et al. Heparin-binding epidermal growth factor-like growth factor is an autocrine growth factor for human keratinocytes. J Biol Chem 1994;269:20060-6.  Back to cited text no. 18
    
19.
Gu Y, Zhang G, Lin M. Quantity research on epidermal growth factor in saliva and epidermal growth factor receptor in biopsy samples of recurrent aphthous ulcer patients. J Stomatol 2008;26:36-9.  Back to cited text no. 19
    
20.
Brozovic S, Vucicevic-Boras V, Mravak-Stipetic M, Jukic S, Kleinheinz J, Lukac J. Salivary levels of vascular endothelial growth factor (VEGF) in recurrent aphthous ulceration. J Oral Pathol Med 2002;31:106-8.  Back to cited text no. 20
    
21.
Girdler N, McGurk M, Aqual S, Prince M. The effect of epidermal growth factor mouthwash on cytotoxic-induced oral ulceration: A phase I clinical trial. Am J Clin Oncol 1995;18:403-6.  Back to cited text no. 21
    
22.
Steed DL. Clinical evaluation of recombinant human platelet-derived growth factor for the treatment of lower extremity ulcers. Plast Reconstr Surg 2006;117:143-9.  Back to cited text no. 22
    
23.
Tüzün B, Wolf R, Tüzün Y, Serdaroǧlu S. Recurrent aphthous stomatitis and smoking. Int J Dermatol 2000;39:358-60.  Back to cited text no. 23
    
24.
Ussher M, West R, Steptoe A, McEwen A. Increase in common cold symptoms and mouth ulcers following smoking cessation. Tob Control 2003;12:86-8.  Back to cited text no. 24
    



 
 
    Tables

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



 

Top
   
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
   Abstract
  Introduction
   Materials and Me...
  Results
  Discussion
  Conclusion
   References
   Article Tables

 Article Access Statistics
    Viewed79    
    Printed0    
    Emailed0    
    PDF Downloaded21    
    Comments [Add]    

Recommend this journal