@2024 Afarand., IRAN

---

ISSN: 2252-0805    The Horizon of Medical Sciences 2018;24(1):47-52

Background
Candida is a yeast fungus, all-around and at the same time opportunistic, commonly found on the skin, the mouth, the digestive tract, the upper respiratory tract, and the beginning of the urinary tract of the healthy people [1]. Although various species of this fungus are known to be the cause of candida fungus infections [2-4], the Candida albicans is the most important and common cause of candidiasis [5-7].
Previous Studies
… [8-14]. It has been shown that the frequency of colonization of Candida albicans is associated with some of underlying diseases. For example, a new study has reported that in the saliva of patients with Psoriasis vulgaris, the presence of Candida albicans is far greater than that of healthy individuals [15]. … [16-18]. In a recent study in Spain, candidiasis oral colonization was significantly associated with a low level of saliva, sugar consumption, and a defect in the artificial teeth of individuals [19]. … [20-22].Some studies have reported the prevalence of Candida albicans infection among health personnel more than the control groups. For example, a study in the United Sates showed that 58% of nurse and 38% of non-nurses were carriers of candida [21]. Some other studies have shown the significant prevalence of Candida species in the mouth among the clients of dental clinics that was about 54.6% [22]. … [23-25].
Aim(s)
Although a high prevalence of fungi colonization has been reported in patients referred to dental clinics [26], and many studies have been done on the difference between fungal flora (microbiome) in healthy and sick individuals [27], the review of international scientific database did not reveal any research on the comparison of oral funal flora of healthy people and oral funal flora of dentists and medical staff. In this study, the transmission of Candida contamination to workers in this profession was not considered. The present study aimed to investigate the relationship between employment in the dental profession and oral colonization of Candida albicans fungus.
Research type
This descriptive study is a case-control study.
Research society, place and time
This research was conducted in 2016 between the community of dentist working in Birjand city and non-clinical staff in administrative department of Birjand University of Medical Sciences.
Sampling method and number
For the case group, 35 individuals (12 dental practitioners and 23 general dentists) from the community of dentists working in Birjand City and 37 individuals from non-clinical staff working in administrative department of Birjand University of Medical Sciences were selected by random sampling method. The criteria for entering the study for both groups were lack of systematic disease, lack of smoking, lack of pregnancy, and the absence of removable prosthesis in the mouth.
Used devices&materials
The researcher presented a referral letter from the faculty of Dentistry to the places to do sampling. Eventually, after describing the process and the objectives of the research, the researcher tried to encourage the members of the case and control groups to cooperate. For doing sampling from the case group, the researcher visited the dental offices in the city and while filling the demographic information of the dentists (age, gender, and work experience), did the sampling from them. All samples were taken by one person and in all cases, the hand pressure was the same. In all samplings, using a sterilized applicator, the surface of the oral mucosa and the back surface of the tongue were scrub, and then the obtained sample was transferred to a sterile swab. Then each of the samples were placed in a centimeter cubic physiology and transferred to the laboratory for a maximum of 2 hours to perform the tests. Experiments on the samples consisted of two steps: first, microscope tests were done. The smear was prepared from the sample and after staining of methylene blue, it was eventually examined by an oily lens (100X). The second stage included cultivating samples and identifying the organism. For this purpose, a Sabouraud dextrose agar culture medium was used. All the samples were inoculated in this culture medium and incubated at 37 ° C for one week. During this period, the culture medium were examined daily for fungus growth. In the event of fungus emergence, a germ tube test was performed. This was performed by taking from the obtained colonies and transferring them to a tube containing human serum and incubating it for 2-4 hours at 37 ° C. By microscopic observation (40X), the presence or absence of the germ tubes of this yeast in the serum was reported. In order to determine the definitive identity of Candida albicans, the resulting organism was cultured in Corn Meal Agar. The emergence of chlamydospore on this medium, was an indicator for the Candida albicans [23]. Although for further certainty, confirmation of culture results was possible by molecular methods such as PCR, no molecular methods were used in the study due to laboratory constraints. Data were analyzed using SPSS 18 software and Chi-square and Fisher`s exact were used to determine the role of demographic variables (occupation, gender, and work experience) in the frequency of colonization of Candida albicans.
Findings by Text
Of the 35 participants of the case group, 6 (17.1%) were positive for Candida albicans cultivation, of which 4 were female and 2 were male. Of 37 participants in the control group, 3 (8.1%) were positive for Candida albicans and 34 (91.9%) were negative in this regard (Table 1).The working experience of subjects in the case group was varied from 2 to 27 years. 19(54.3), 10(28.6%), and 6(17.1%) had the working experience of less than 5 years, between 5 and 10 years, and over 10 years respectively. Among 19 dentists with working experience less than 5 years, 3 were identified with the colonies. This is, while, among the dentists with working experience between 5 and 10 years, 2 cases were identified with colonies, and among the dentists with working experience over 10 years, only one case was identified with colonies. Although the number of positive Candida albicans in oral samples of dentistry group (17.1%) was as twice as the number of positive cultivation in the control group (8.1%), no significant difference was observed between these two groups (p>0.05). In addition, there was no statistically significant difference between the gender and the frequency of oral contamination with Candida albicans (p>0.05). There was also no significant relationship between the working experience and frequency of Candida albicans (p>0.05).
Main comparison to the similar studies
… [27-29].The study of Negroni et al. has shown that the prevalence of Candida infection in dentistry students is more than the normal level of contamination of this organism in the community [30]. A similar study by Matlabnejad et al. in Iran, also, has shown such a difference in the two groups [23]. The question is: Why did not the findings of this research show a significant difference? In both of the above studies, the case group included those dental students who worked daily on dental clinics in dentistry clinic. However, in the present study, the case group included dentists with at least two years of work experience that 66% of them were visiting the patients only their personal clinic and 34% of them were dental specialists who were expected to adhere to high levels of infection prevention and control standards. Regardless of the lower health status in training dental clinics compared to private clinics, dental students may also be much weaker in their compliance with the prevention and control guidance of infection than dentists with high experience, all of which naturally leads to increased transmission of contamination. In addition, it seems that the level of oral health observation by dentists exist among other health care workers. … [31, 32].
Suggestions
Given the applied goals of this study, observing the principles of infection control and personal protection by dentists are recommended and this may be influential in the reduction of infection in this occupational group. For additional studies, more samples are suggested to compare the levels of infection with Candida albicans in different clinical settings.
Limitations
The limitations of this study were obtaining the consent of dentists to participate in the research, as well as attempt to take the equal samples from the oral cavity of the participants.
Conclusions
Dentists are not more at risk of oral infection and colonization than non-clinical occupations.
Acknowledgments
The authors thank the collaboration of the staff of the Department of Microbiology of the Central Laboratory of Valiasr Hospital in Birjand.
Conflict of interest
Non-declared
Ethical Permissions
This research was approved by the ethics committee of Birjand University of Medical Sciences with the code of 1394-04-11.
Funding Sources
The findings of this paper are the result of the approved research project (Code 93.3) at Birjand University of Medical Sciences and has been funded by this project.

TABLES and CHARTS

Show attach file