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 Table of Contents  
ORIGINAL RESEARCH
Year : 2021  |  Volume : 12  |  Issue : 2  |  Page : 67-72

Oral Complications of Dental Prosthetic for Patients after Chemotherapy and Radiotherapy Treatment


Prosthodontic Department, Faculty of Dentistry, Al Azhar University, Gaza, Palestine

Date of Submission09-May-2020
Date of Decision08-Jul-2020
Date of Acceptance07-Aug-2020
Date of Web Publication26-Jul-2021

Correspondence Address:
Waseem Moshtaha
Assistant Professor, Prosthodontic Department, Faculty of Dentistry, Al Azhar University, Gaza
Palestine
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/denthyp.denthyp_57_20

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  Abstract 


Introduction: Chemotherapy‐ and radiotherapy‐induced oral complication represents a therapeutic challenge frequently encountered in cancer patients. This side effect causes significant morbidity and may delay the treatment plan, as well as increase therapeutic expenses. The current study aimed to measure possible changes in oral microflora in cancer patients wearing dentures before starting and within 3 and 7 days of the first course of chemo/radiotherapy. The researcher seeks to investigate the association between these changes and the distressing oral problems compared with control patients. Material and Methods: The current study performed based on the case-control design in which 46 cancer patients who wear dentures and meet the inclusion criteria were selected from 80 patients as cases or tested group. Another 46 cancer patients who did not wear dentures were matched to be the control group. Based on the international safety standard, the oral microflora of the buccal mucosa was collected and cultured from two saliva samples at T0 (before chemotherapy), T1 (the day after chemotherapy), and T2 (7 days after chemotherapy). A series of descriptive and MacNemar analysis and other statistical tests included independent and paired t-tests, chi-square, were performed to determine significance at P < 0.05. Results: The current study revealed that that 25 patients (54.34%) who developed plaque that consisted predominantly of saprophytic Gram-positive cocci (Streptococcus spp., Leuconostoc spp., Granulicatella spp. and Gemella spp.). By investigation, 15 of these patients underwent chemotherapy/radiotherapy (60%). The other 21 patients (45.66%) developed periodontal pathogens (F. nucleatum, P. gingivalis, Actinobacillus spp. and Pep. micros). Regarding time variation (T0, T1, and T2), no significant differences were reported in bacterial changes. Furthermore, the control group swabs showed that the bacterial count did not change significantly during the observation period and both qualitative and quantitative bacterial growth was not significantly differed from the case group. Conclusion: The results of the current study indicate that there were no significant changes in the growth of microflora observed in the dental plaque and wearing dental of cancer patients within 7 days of the first course of chemo/radiotherapy. Furthermore, no correlation observed between oral mucositis and specific microorganisms.

Keywords: Cancer patients, chemotherapy, denture, oral microflora, saliva


How to cite this article:
Moshtaha W. Oral Complications of Dental Prosthetic for Patients after Chemotherapy and Radiotherapy Treatment. Dent Hypotheses 2021;12:67-72

How to cite this URL:
Moshtaha W. Oral Complications of Dental Prosthetic for Patients after Chemotherapy and Radiotherapy Treatment. Dent Hypotheses [serial online] 2021 [cited 2021 Sep 25];12:67-72. Available from: http://www.dentalhypotheses.com/text.asp?2021/12/2/67/322522




  Introduction Top


Oral complication represents a major non‐hematologic complication of chemotherapy and radiotherapy associated with significant morbidity; pain, odynodysphagia, dysgeusia, and subsequent dehydration and malnutrition reduce the quality of life of affected patients.[1] Several studies have conducted to evaluate the effect of serum vitamin C and antioxidants on gingival health, periodontitis, and CAD. These studies showed that patients with CAD and periodontitis plus CAD presented lower levels of salivary and serum vitamin C compared to healthy subjects and periodontitis patients. hs-CRP was a significant predictor of decreased salivary and serum vitamin C levels.[2],[3],[4] Most people know the most serious side effects more common cancer treatments like nausea and hair loss. However, few people know that a third of patients undergoing cancer treatment suffer from complications of the mouth. Complications are medical problems that occur as a result of an intervention, treatment, or illness.[5],[6] Oral complications occur in the mouth. Cancer patients have a high risk of oral complications. A large number of cancer treatments, including chemotherapy and radiation therapy, can harm the oral health of the patient. Oral health is about well with the whole mouth, including the teeth, gums, the mucous membrane, and the saliva-producing glands (salivary glands).[7] Oral complications can make it difficult to eat, talk, chew, or swallow. These problems can affect the patient’s health and quality of life. They can even prevent the patient from finishing the treatment. In some cases, when oral complications are serious, their effects on cancer treatment may be important, for example, it may be necessary to decrease the doses of treatment; treatment schedules can be changed, processing may be postponed, treatment can be stopped completely.[5],[8],[9]

Oral complications occur in almost 40% of patients undergoing chemotherapy, in about 80% of those who have a stem cell transplant and almost everyone who undergoes radiation therapy for a head and neck tumor.[10],[11] Before starting treatment, patients must understand the cause of the complications to treat it and reduce symptoms and improve their quality of life. The oral defense mechanisms are compromised by cytotoxic chemotherapy, either by direct mucosal damage (mucositis which is a multifactorial disease and results in part by changes in oral bacterial microflora) or by immunosuppression resulting from neutropenia related to cancer or to the chemotherapy used to treat it potentially causing an overall shift in oral microflora.[7]

The cancer treatment caused alterations in oral microbiota which may lead to the emergence of potential pathogens and subsequent other systemic health problems to the patients. Hence, clinical guidelines and recommendations have been presented to control oral microbiota in patients with cancers, but also in this field, the scientific evidence is weak, and more controlled studies are needed for further conclusion.[8],[12] In the Gaza strip, there are many types of cancer, but until now, no study conducted to show the relationship between changes in oral microflora and chemo/radiotherapy. Therefore, this study aimed to assess the oral complications of dental prosthetic for patients after chemotherapy and radiotherapy treatment and to investigate if there an association between these changes and the distressing oral problems compared with control patients through exploring the changes in some of the oral microflora expected in cancer patients during chemotherapy and radiotherapy treatment.


  Material and Methods Top


Study design

The present study was performed based on the controlled prospective cohort study.

Sample size

We enrolled 46 patients (27 men and 19 women, aged 30–65 years) with known solid tumors wearing a denture for at least one year. The collected patients had no previous radiotherapy or chemotherapy and they don’t follow any recent anti-microbial or anti-viral treatment. The data was collected from the main two-oncology departments in Gaza Strip. [Table 1] shows the categories of patients based on their age, gender, and type of cancer.
Table 1 A patient classification based on gender, diagnosis, age, and treatment

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The study conformed to the Helsinki Declaration and approved by the Medical Ethical Committee of Al Azhar University-Gaza. All patients gave their written informed consent.

The study was conducted from the first of July 2019 up to December 2019 and involved 80 patients who are wearing a denture and will receive chemotherapy or radiotherapy at AL-Rantisi hospital. Inclusion criteria were a history of no medical problems and a history of no medications. The samples were obtained twice from the same patient before chemotherapy/radiotherapy and at two stages after receiving doses of chemotherapy/radiotherapy. After the first samples (before starting treatment), thirty-four patients from the whole sample (80 patients) were excluded from the current study because they have previous oral and bacterial growth. The control group of the previous 46 patients were 60 cancer patients who undergoing chemotherapy/radiotherapy but did not wear dental (patient gender, age, and type of cancer have matched between case and control groups). All patients who used antimicrobial agents were excluded.

In the current study, we categorized the patients into two groups: the first group consisted of 30 patients undergoing the first course of chemotherapy (docetaxel or 5-fluorouracil and oxaliplatin), and followed with radiotherapy treatment. The second group includes 16 patients who underwent radiotherapy (no chemotherapy) due to the stage of the tumors (late-stage) and/or they did not have good immunity (adequate numbers of platelets and leukocytes).

The oral microflora was, swabbed, collected and cultured from wearing dental and plaque specimens. All samples were collected at different stages:
  1. T0: immediately before chemotherapy.
  2. T1: 1 day after infusion.
  3. T2: 7 days after infusion.


The swabs were taken from the wearing dental and the supragingival plaque of the right lower premolars using sterile swab at least 2 hours after the last meat. All specimens were treated within the following 4 h. Starting with dilution, 100 μl of each dilution was placed in a flat plate (Schaedler Selective Blood Agar plates) that supplemented with 5% bovine blood (Biolife). After that, the plates are incubated in 80% nitrogen/10% hydrogen/10% CO2 at 35°C to monitor different types of microorganisms (P. gingivalis, F. nucleatum, Actinobacillus spp. and Peptostreptococcus micros).

Finally, an additional 100 µl was plated on Columbia agar containing 5% bovine blood in 5% CO2 to monitor another group of microorganisms (Gemella spp., Streptococcus spp., Leuconostoc spp., and Granulicatella spp).

The diagnosis of microorganisms was performed by standard procedures.[13] Besides, the production of a set of metabolic enzymes (as tested with Rapid ID 32A and Rapid ID32 Strep)[14],[15] to facilitate the bacterial count that expressed in MCF, equivalent to 1.5×108 cells/ml.

Regarding the statistical analysis, All subject data was encoded and analyzed using SPSS Statistics (version24, IBM Corporation, Somers, NY). Descriptive, frequencies, MacNamara analysis, and statistical tests included independent and paired t-tests, chi-square, and significant results were reported at P < 0.05. The normality test was done and showed that data distributed normal “Kolmogorov test (P value = 0.198) and Shapiro (P value = 0.435)”


  Results Top


[Figure 1] illustrates the incidence rate of different cancer types among males and females based on the annual report of the Ministry of Health.[16]
Figure 1 Incidence rate of different cancer types [A: Breast; B:Colon; C:Leukemia; D:Brain; E:Thyroid; F:Ovary; G:Lung; H:NHL; I:Rectum; J:Liver; K: Kidney; L:Bladder; M:Prostate; S:Stomach].

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[Table 2] illustrates the WHO classification (classification of mucositis according to the World Health Organization, 1979)[17] allows a better characterization of mucositis buccopharyngeal and is necessary for good clinical analysis as well as for evolutionary monitoring.
Table 2 Characterization of buccopharyngeal mucositis (WHO)

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The classification of criteria for toxicities to chemotherapies defined by the National Cancer Institute (NCI-CTC [Common Toxicity Criteria] version 3.0) also produced an assessment of mucositis at the buccopharyngeal level as shown in [Table 3].
Table 3 Criteria of toxicity to chemotherapy at the buccopharyngeal level

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In the COP situation, the main complaint of the patient will experience dyspepsia or odynophagia sometimes going as far as dysphagia; note that a certain proportion of COPs are asymptomatic. Upon inspection, depending on the forms of presentation, may encounter thrush, an erythema form atrophic tease, and a pearl. In cases of resistance to local treatment adapted and well-led, the clinician will be led to perform kill fungal samples to determine the species involved and its sensitivity to agents’ anti-infective (fungi-gram).

The microbial analysis of Oral mucositis was scored based on the World Health Organization (WHO) criteria. The results revealed that 27 cases (58.6 %) showed non-keratinized sites; 19 with grade 1 and eight with grade 2. No ulcerations on the keratinized mucosa were reported.

[Table 4] shows that 25 patients (54.34%) who developed plaque that consisted predominantly of saprophytic Gram-positive cocci (Streptococcus spp., Leuconostoc spp., Granulicatella spp. and Gemella spp.). By investigation, 15 of these patients underwent chemotherapy/radiotherapy (60%). The other 21 patients (45.66%) developed periodontal pathogens (F. nucleatum, P. gingivalis, Actinobacillus spp. and Pep. micros).
Table 4 Mean numbers of bacteria in the study population (cases with chemo/radiotherapy)

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Besides, half of these patients (50%) developed periodontal pathogens have received chemotherapy. All tested group showed no P. gingivalis. Actinobacillus spp. were the least frequently found the periodontal pathogen in the test group (only 3 in cases; 6.5%), while Streptococcus spp was the most frequently found (9 out of 46; 19.5%).

Regarding time variation (T0, T1, and T2), no significant differences were reported in bacterial changes as shown in [Table 4] and [Figure 2]. Regarding the control group, the collected swabs showed that the bacterial count did not change significantly during the observation period as shown in [Figure 3]. The reported differences in both qualitative and quantitative bacterial growth between the groups (case and control) were not significant [Figure 4].
Figure 2 Mean numbers of bacteria in the samples in the test group (case group).

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Figure 3 Mean numbers of bacteria in the samples in the test group (control group).

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Figure 4 Cross-sectional analysis of mean bacterial counts between the two groups.

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  Discussion Top


The current results revealed that the presence of saliva in the wearing dental and supragingival plaque in addition to the wearing of denture offered good conditions allowed the growth of aerobic and anaerobic organisms.[18] The study of Isola et al. showed the effect of antioxidant profiles in saliva and serum in patients with periodontitis.[2],[3] The results discussed the possible complications resulted from radiotherapy or chemotherapy for patients wearing dentures. This environment helps the gathering of complex microflora dominated by Gram-positive bacteria, particularly streptococci. This type of flora acts as the oral flora during chemotherapy/radiotherapy treatment, and this result agreed with the previous study.[17] During the day and particular after eating, the microflora gathered in the mouth and exposed to several modifications (for that all swabs were taken after 2 hours from the last meat). To minimize these variations, the samples standardized and the microorganisms monitored based on the known saprophytic species of the oral cavity (Streptococcus spp., Leuconostoc spp., Granulicatella spp. and Gemella spp.) and these species associated with periodontal pathology (P. gingivalis, Actinobacillus spp., Peptostreptococcus spp. and F. nucleatum).

These types of periodontal pathogens can associate with periodontal diseases in patients with partially or completely suppressing the immune response.[19],[20],[21] In the same line, the current study revealed that the highest bacterial count was Streptococcus. However, no complain reported from those patients. Generally, none of the examined patients (either case or control) exhibited any serious sign or protest in periodontal pathology and periodontal probing. The dental plaque flora is very sensitive and influenced by other factors, such as smoking, nosocomial infections, dietary type, gastroesophageal reflux, and oral treatments. Topical, oral, and parenteral antimicrobials before and during cancer chemotherapy should alter the quantitative and qualitative oral microflora profile.[22] Based on that, it is not easy to expect the type of aggregated bacteria.

Most of the oral bacterial changes involved Gram-negative organisms such as Enterobacteriaceae and Pseudomonas spp.[19] There is no significant variation reported in the qualitative and quantitative of microflora due to chemo/radiotherapy treatment. Moreover, there is no signs or clear pattern of mucositis or changes in the oral microflora.[5] Previous related studies showed a 5-10% reduction in the oral microflora for those patients who wear dental and underwent chemo/radiotherapy.[7],[23] Besides, no significant change reported in the remaining oral bacteria through the evaluation levels (T0, T1, and T2). At the end of treatment, there is no obvious change in the bacterial microflora due to receiving chemo/radiotherapy. Also, the analysis revealed no significant differences between the cases and control groups. Around 60% of the tested cases showed Gram-positive cocci (Saprophytic species of the oral cavity), and the remaining of the patients (∼ 40%) had bacterial flora that also had periodontal-pathogenic species. The difference that reported between the case and control groups was the incidence of mucositis, which showed only in the case group. It worth mentioning that the selected patients have a good immune response, which may inhibit bacterial pathogenicity.[24] The study showed that patients with high leukocyte (efficient immune response) showed low microflora changes (more than 32% of patients have WBC count between 5,000 and 10,000 per microliter of the whole blood). Moreover, patients with low immunity are vulnerable to systemic infection when they gather granulocytopenia with mucositis. It is already proved that some oral bacterial increase aggravation of mucositis (Klebsiella), but is not easy to attribute systemic mucositis to the local oral infection.[25] For example, in a previous study,  Porphyromonas gingivalis Scientific Name Search detected and showed oral ulceration for patients with low immuno-response due to hematopoietic stem cell transplantation.[26] P. gingivalis has known virulence factors that invade by the presence of epithelial cells,[27] and create a lipopolysaccharide capsule that eventually produces pro-inflammatory cytokines.[28] This type of bacteria (P. gingivalis) was not detected in patients included in the current study (neither cases nor controls).


  Conclusion Top


The current study showed the possible oral complication of cancer patient wearing dental after their chemo/radiotherapy process. Based on the case-control design, the 46-cancer patient was selected from 80 patients that wear dental and prepared for chemo/radiotherapy. The same number of patients, who not wearing dental, were selected to be as a control group (cancer types have also matched). According to the obtained results, no significant changes occur in the microflora in dental plaque or dental wearer in cancer patients within the first seven days (after starting treatment). Also, no correlation observed between oral mucositis and specific bacteria. Further studies are recommended to prove the correlation of wearing dental and the possibility of mucositis by increasing sample size and time of monitoring (more than 7 days) and the association between different vitamins and antioxidants on the gingival health and periodontitis. The current study encourages the researcher to increase oral follow-up of cancer patients during the chemo/radiotherapy.

Financial support and sponsorship

Nil.

Conflict of Interest

The authors declare that they have no conflict of interest.



 
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He J, Huang W, Pan Z, Cui H, Qi G, Zhou X et al. Quantitative analysis of microbiota in saliva, supragingival, and subgingival plaque of Chinese adults with chronic periodontitis. Clin Oral Investig 2012;16:1579-88.  Back to cited text no. 12
    
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    Figures

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



 

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