|Year : 2016 | Volume
| Issue : 4 | Page : 265-270
Clinical effects of reservoirs on gingival health using two different concentrations of home dental bleaching agents on fluorosed teeth: A comparative study
Jayaprada R Surakanti1, Harikumar Vemisetty1, Ravi C.P. Venkata1, Roopadevi Garlapati1, Ramya Sree Bolishetty1, Aruna Kumari2
1 Department of Conservative Dentistry and Endodontics, Kamineni institute of Dental Sciences, Narketpally, Telangana, India
2 Department of Oral Pathology, Kamineni institute of Dental Sciences, Narketpally, Telangana, India
|Date of Web Publication||23-Dec-2016|
Jayaprada R Surakanti
Department of Conservative Dentistry and Endodontics, Kamineni Institute of Dental Sciences, Narketpally, Nalgonda - 508 254, Telangana
Source of Support: None, Conflict of Interest: None
Objectives: To evaluate the effect of concentration and influence of reservoirs on the gingival mucosa of patients submitted to at-home bleaching with 10% and 35% carbamide peroxide (cp).
Materials and Methods: A total of 20 patients were submitted to home bleaching with a 10% cp gel for 2 h/day for 3 weeks and 35% cp gel for 30 min/day for 3 weeks (n = 10). The custom-made mouth trays were made with a reservoir on only the left side and cut anatomically 1 mm beyond the gingival margin. Smears of the gingival mucosa were obtained by the exfoliation cytology in liquid media technique before (control), immediately after, and 30 and 45 days after the treatment. The samples were processed in the laboratory and evaluated for inflammation. Statistical analysis was carried out by McNemar test, two proportions test, independent paired t-test, and Wilcoxon test with a level of significance of 1%.
Results: The presence of a reservoir in the custom tray resulted in an increase of inflammation immediately after the bleaching procedure. No significant differences were found in the degree of inflammation between the two groups at different period of observations. (P > 0.01).
Conclusion: Ten percent and 35% cp bleaching gel caused gingival inflammation immediately after the procedure and persisted until 45 days after the bleaching treatment. The use of a reservoir in the custom tray for home bleaching resulted in higher rates and higher intensity of gingival inflammation.
Keywords: Carbamide peroxide, exfoliative cytology, fluorosis, gingival inflammation, reservoir
|How to cite this article:|
Surakanti JR, Vemisetty H, Venkata RC, Garlapati R, Bolishetty RS, Kumari A. Clinical effects of reservoirs on gingival health using two different concentrations of home dental bleaching agents on fluorosed teeth: A comparative study. J NTR Univ Health Sci 2016;5:265-70
|How to cite this URL:|
Surakanti JR, Vemisetty H, Venkata RC, Garlapati R, Bolishetty RS, Kumari A. Clinical effects of reservoirs on gingival health using two different concentrations of home dental bleaching agents on fluorosed teeth: A comparative study. J NTR Univ Health Sci [serial online] 2016 [cited 2020 Mar 28];5:265-70. Available from: http://www.jdrntruhs.org/text.asp?2016/5/4/265/196560
| Introduction|| |
Dental fluorosis is characterized by hypoplasia of the enamel resulting from long-term ingestion or exposure to high levels of fluoride during the phase of tooth mineralization.  Clinical dental fluorosis is characterized by lusterless, opaque white patches in the enamel, which may become striated, mottled, or pitted, or may be stained yellow to dark brown. With increasing degree of severity, the teeth are more likely to be discolored.  Bleaching has been universally accepted as a method of lightening discolored teeth, and several bleaching systems have been introduced in response to the demand in esthetic dentistry. At-home bleaching system is the most frequently recommended treatment for vital teeth.  The evaluation of the efficacy and safety of bleaching systems has received considerable attention because of their local side effects on oral soft tissues. ,,
Clinical trials have evaluated gingival health by measuring the bleeding index, gingival index, plaque index,  numerical scales,  questionnaires.  Histopathologic studies are also used for the assessment of gingival irritation and are more accurate but too invasive, because biopsy of the tissue must be obtained for cell evaluation.  Exfoliative cytology is the study of cells that have been extracted or removed from the epithelial surface of several organs. , It is noninvasive, painless, and can be more accurate to assess gingival inflammation. Oral samples are obtained by a wooden paddle or a special brush called cytobrush, whose objective is to obtain the largest possible amount of cell samples, which are taken for Pap staining test. ,
Till today, no author has comparatively evaluated the effects of bleaching agents on gingival health of fluorosed teeth. Thus, the aim of this clinical study was to evaluate the effects of 10% cp and 35% cp bleaching agents with and without reservoirs on gingival health using liquid based exfoliative cytology (LBC).
| Materials and Methods|| |
The experimental protocol of the present study was approved by the ethics committee of the Kamineni Education Society, Narketpally, Telangana.
Twenty voluntary patients (15 males and 5 females) in good oral and general health having a desire to lighten their fluorosed maxillary anterior teeth participated in this study. Participants were randomly assigned to two groups (n = 10) according to the bleaching agents [Table 1].
For inclusion in the study, participants had to be nonsmokers, had not submitted to dental bleaching before the study, and without extensive restorations in anterior teeth. For exclusion, the selected participants did not have gingival inflammation prior to the study
Custom tray facbrication
Maxillary alginate impressions (hydrogum) were made and dental stone models (neelkanth) were cast for fabrication of bleaching trays. Ethylvinyl acetate trays were made with a heat/vacuum tray-forming machine (easy-vac) and the trays were trimmed to fit each model perfectly [Figure 1] and [Figure 2]. Patients were instructed on how to care for and use the trays correctly.
The fit of the tray was carefully inspected, and adjustments were made to ensure that the tray did not abrade the tissue and was well adapted. Participants were instructed verbally and via hands-on practical demonstration in the use of the bleaching gel.
Group 1: Treated with at home bleaching system opalescence 10% cp (Ultradent, USA) was used 2 hours per day for 21 days and
Group 2: Treated with 35% cp (Ultradent, USA), for 30 min for 21 days. The participants were asked to return the trays at the completion of treatment.
Exfoliated cells of the gingival margin between the maxillary canine and premolar were obtained [Figure 3]. Initially, the mouth was rinsed with water to remove excess debris and bacteria. The squamous epithelial cells were collected using a cytobrush and universal collection medium kit (Uprep LBC pap test kit Regenix drugs Ltd India). The cells were collected before, immediately after, and 30 and 45 days after the bleaching treatment. To compare the degree of inflammation after dental bleaching, the cells were collected bilaterally at the sides with and without reservoirs. Then, the same brush head was detached and suspended in LBC vial containing preservative fluid, which was transferred to the cytopathology laboratory for further processing as per the prescribed protocol for the LBC equipment.
Each slide was assessed using a binocular light microscope at 100× magnification (LABOMED., USA). Inflammatory cytologic results were categorized as absent (0 cells/field), mild (1-5 cells/field), moderate (6-20 cells/field), or severe (>20 cells/field). 
All data were tabulated and statistical tests were performed with the Statistical Package for the Social Sciences (SPSS) version 19. The McNemar test, independent paired t-test, two proportions test, and Wilcoxon test were used.
| Results|| |
The presence of a reservoir in the custom tray resulted in an increase of inflammation only immediately after the bleaching procedure as detected by the two proportions test in both the groups. After 30 and 45 days, the difference between inflammation on the sides with and without a reservoir and between two groups was not statistically significant [Table 2] and [Table 3]. The McNemar test found statistically significant differences among the control group (before) and other periods of evaluation after the bleaching procedure (immediately after and 30 and 45 days after) with both 10% and 35% cp, characterized by an increase in the amount of inflammation cells [Graphs 1 and 2]. By comparing 10% and 35% cp, inflammatory cells were more with 35% cp during different periods of observation, however, it was not statistically significant as compared by using independent paired t-test (P > 0.01) [Graphs 3 and 4].
|Table 2: No. And percentage of patients submitted to home bleaching with 10% carbamide peroxide with inflammation during different periods of observation (N=10)|
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|Table 3: No. And percentage of patients submitted to home bleaching with 35% carbamide peroxide with inflammation during different periods of observation (N=10) |
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| Discussion|| |
Effects of bleaching agents on gingival health have not been well described in the literature. The present study aimed to elucidate the effects of home bleaching on gingival health. Bleaching has been universally accepted as a method of lightening discolored teeth, and several vital bleaching systems have been introduced in response to the demand in modern esthetic dentistry. 
At-home bleaching system is the most frequently recommended treatment for vital teeth with mild fluorosis. The evaluation of the efficacy and safety of bleaching systems has received considerable attention. Local side effects on oral soft tissues caused by peroxides released into the oral cavity from bleaching systems are reported in the literature as gingival irritations such as gum burning or erosions of the gingiva. 
The signs of gingival inflammation after dental bleaching treatments may not be observed by visual inspection. Therefore, an accurate method, such as exfoliative cytology, must be used to confirm the presence or absence of inflammatory cells, as well as the intensity of the inflammation. Exfoliative cytology was recommended by Papanicolaou and Traut as a practical method for the early diagnosis of uterine cervical cancer, and there is currently no doubt regarding its efficacy. Because the method is noninvasive, rapid, and inexpensive, it has been applied in different areas, including dentistry. , Bleaching has been reported to cause a number of side effects. The most common side effects are tooth hypersensitivity and gingival irritation. These effects are correlated with several factors, such as pH and the peroxide concentration of the bleaching gel, the number and length of applications, among other factors. All of the observed and most of the reported oral adverse effects are mild and transient in nature.
In the present study, immediately after treatment, the reservoir side exhibited a prevalence of moderate inflammation, whereas on the nonreservoir side, mild inflammation was noted. At the 30-day observation, the intensity of inflammation was similar for both sides of the tray. After 45 days, prevalence of moderate inflammation was seen on the reservoir side. One possible explanation for these findings could be related to custom-made trays. The anatomic design, 1 mm beyond the gingival margin, and the flexibility of the silicone tray could have allowed extrusion of the bleaching gel. Total avoidance of soft tissue contact is impossible. According to Haywood et al., the presence of reservoirs decreases the retention of the tray, allowing more room for the gel but also reducing the adaptation of the tray. This could explain why the presence of a reservoir caused more gingival inflammation in this study. The present study revealed the clinical signs of inflammation in the participants after 1 week of bleaching on only the reservoir side of the tray. In a clinical investigation by Matis et al.,  no difference was found in gingival sensitivity between areas bleached with and without reservoirs.
The presence of severe inflammation 45 days after bleaching was observed few cases. This fact could be explained by the possible residual effect of the bleaching agent or the plaque accumulation due to patient's negligent hygiene. According to Firat et al., the effect of bleaching systems on the gingiva and the levels of IL-1b and IL-10 in gingival crevicular fluid and observed that home and chemically activated bleaching systems could be considered safer in tooth whitening and maintaining gingival health when compared with a light-activated bleaching system.  Kirsten et al. investigated the effect of reservoirs on gingival inflammation after home dental bleaching and found that use of a reservoir in the custom tray for home bleaching resulted in higher rates and higher intensity of gingival inflammation.  Furukawa et al. evaluated the cytotoxic effects of hydrogen peroxide on cultured human fibroblasts (HGFS) and found that damaged HGFS expressed proinflammatory cytokines.  It is also important to perform some histological studies including oral soft-tissue epithelia and possible DNA alterations to verify that these results are reproducible and consistent.
Therefore, indiscriminate, frequent, or prolonged treatments might increase potential damage to tissues. Dental clinician must be careful to indicate and supervise bleaching procedures [Figure 4].
| Conclusion|| |
Bleaching has proven to be a cost-effective, dramatic, simple, and safe treatment option. No significant difference was found between two groups. 10% and 35% cp home bleaching caused gingival inflammation not only immediately after the procedure but also until 45 days following the bleaching treatment. The use of a reservoir in the custom tray for home bleaching resulted in higher rates and higher intensity of gingival inflammation.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3]