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 Table of Contents  
ORIGINAL ARTICLE
Year : 2021  |  Volume : 11  |  Issue : 1  |  Page : 48-54

Objective comparison of three different treatment modalities in the esthetic improvement of mild-to-moderate dental fluorosis: A randomized clinical trial


Department of Pedodontics and Preventive Dentistry, BDCH, Davangere, Karnataka, India

Date of Submission08-May-2021
Date of Acceptance27-May-2021
Date of Web Publication9-Aug-2021

Correspondence Address:
Dr. Gishelle Swapna Quadros
Department of Pedodontics and Preventive Dentistry, BDCH, Davangere, Karnataka
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijohs.ijohs_10_21

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  Abstract 


Objective: To compare and evaluate esthetic improvement following resin infiltration, vital bleaching, and diode laser bleaching in mild-to-moderate fluorosis conditions immediately after treatment, 1 month, and 6 months postoperatively.
Study Design: Sixteen patients with Central and lateral incisors showing mild-to-moderate fluorosis according to modified Dean's fluorosis index were selected and simple randomization was done to allocate the teeth to resin infiltration group, vital bleaching group, diode laser bleaching group, and control group. Esthetic improvement posttreatment was assessed using digital image analysis using Adobe Photoshop software and color change (ΔE) was calculated.
Results: The inferential statistics included Kruskal–Wallis test and Friedman's ANOVA test. Vital bleaching showed the highest esthetic improvement followed by diode laser bleaching, vital bleaching, and control group at all the different time intervals. The results, however, were not statistically significant.
Conclusion: All the three treatment measures brought about esthetic enhancement with the vital bleaching group showing slightly better results when compared with other study groups.

Keywords: Dental esthetics, dental fluorosis, diode laser bleaching, resin infiltration, vital bleaching


How to cite this article:
Quadros GS, Sugandhan S, Deepak B M, Basappa N, Raju O S, Shagale AM. Objective comparison of three different treatment modalities in the esthetic improvement of mild-to-moderate dental fluorosis: A randomized clinical trial. Int J Oral Health Sci 2021;11:48-54

How to cite this URL:
Quadros GS, Sugandhan S, Deepak B M, Basappa N, Raju O S, Shagale AM. Objective comparison of three different treatment modalities in the esthetic improvement of mild-to-moderate dental fluorosis: A randomized clinical trial. Int J Oral Health Sci [serial online] 2021 [cited 2021 Nov 28];11:48-54. Available from: https://www.ijohsjournal.org/text.asp?2021/11/1/48/323521




  Introduction Top


Fluorides promote oral health in multiple ways, but at the same time, it also behaves as a double-edged sword, the downside to this extensive use of fluoride has paved way for dental fluorosis.[1],[2] Dental fluorosis is not a condition that causes physical discomfort to the patient. However, it is possible to observe negative effects of fluorosis, such as embarrassment due to compromised esthetics of the teeth which can have a significant psychological impact on the patient.[3]

Currently, there is a wide array of treatment strategies available that are either noninvasive or invasive in nature. The various treatment approaches available involve vital bleaching, microabrasion, diode laser bleaching, resin infiltration, veneering, or artificial crowns.[4]

Bleaching is accepted as the least aggressive method for treating discolored teeth. McInne's technique for the removal of fluorosis stains has been shown to be easy, fast, and effective. The use of diode laser bleaching which is another minimally invasive treatment option for dental fluorosis providing the patient with an advantage of little or no intraoperative and postoperative sensitivity.[5] Resin infiltration is yet another alternative therapeutic approach for masking fluorotic lesions. The goal of this treatment is to occlude the micro porosities within the lesion body by infiltration with low-viscosity light-curing resins.[6],[7]

Endemic conditions like fluorosis require treatment options that are simple, efficient, and time-saving.[6] There is a need to objectively assess which among the available treatment options are most efficient with regard to showing maximal esthetic improvements and at present, the available literature shows a dire scarcity with this regard.

Hence, in the present study, we intend to compare and evaluate, the relative efficacy of vital bleaching, diode laser bleaching, and resin infiltration for the esthetic improvement of mild to moderately fluorosed in children of 8–12 years.


  Subjects and Methods Top


Ethics

The study was conducted on children visiting the Out-Patient Department of Pedodontics and Preventive Dentistry at Bapuji Dental College and Hospital, Davangere, Karnataka. The work has been approved by the appropriate ethical committees related to the institution, in which it was performed and with the Helsinki Declaration of 1975, as revised in 2000. Informed consent was taken from the parent/guardian and assent was obtained by the children after explaining the entire treatment procedure. The calculated sample size was 16.[6] The age of the children in the sample ranged from 8 to 12 years.

Study design

The present study was a randomized, prospective, experimental, in vivo study.

Selection and description of participants

Central and lateral incisors having mild-to-moderate fluorosis according to modified Dean's fluorosis index were selected and simple randomization was done to allocate the teeth to resin infiltration group, vital bleaching group, diode laser bleaching group, and control group. The inclusion criteria included central and lateral incisors with mild-to-moderate fluorosis according to modified dean's fluorosis index. Patients who have given written consent and assent for treatment and caries-free teeth. The exclusion criteria included teeth with nonfluoride stains of teeth. Patients with fractured, carious, or grossly decayed teeth. Patients having dry mouth, any enzymatic disorders, parafunctional habits and with poor oral hygiene.[4] All the participants received complete oral prophylaxis and preoperative photographs were taken.

Standardization of pre- and post-operative photographs[8]

After oral prophylaxis, the cheek retractors were inserted, and the child was asked to bite in edge-to-edge relation. Photographs were taken after allowing the tooth to dry for 105 s as tooth dryness affects the refractive index and hence the color perception of the tooth. The camera was held at a 45° angle while taking photographs to minimize specular reflection. The distance between the lens and the teeth as well as the lighting conditions was kept constant for all photographic assessments.

Isolation of the teeth

After the placement of cheek retractors, the teeth were isolated using resin dam. Teflon tape was then applied to the teeth adjacent to the tooth of interest. Each patient was protected with eyeglass and a body drape and the operator was wearing gloves, protective eyeglass, and a mouth mask.

Technical information

Vital bleaching using McInnes solution[4]

McInnes solution which was used for vital bleaching was freshly prepared before each procedure. The composition of McInnes solution used was 1 ml of 36% HCl, 1 ml of 30% H2O2, 0.2 ml of Diethyl ether. The freshly prepared bleaching solution was applied over the fluorotic lesion using a cotton applicator. The solution was reapplied as often as needed until an acceptable esthetic improvement was achieved or to a maximum extent of 5 min.

Resin infiltration technique[5]

The surface layer of the tooth was eroded by application of a 15% hydrochloric acid gel (icon-etch) for 120 s. To achieve a homogeneous etching pattern, the manufacturer's recommendation to stir the gel from time to time must be followed during the application, using the smooth surface-tips included in the respective product kit. Subsequently, the etching gel was thoroughly washed away for 30 s using a water spray. To remove the water retained within the micro porosities of the lesion body, lesions were desiccated by application of ethanol for 30 s (icon-dry) and subsequent air-drying. To maximize water removal, this step was repeated at least once. A resin infiltrant (icon-infiltrant) was applied on the lesion surface using smooth surface-tips and allowed to penetrate for 3 min, resin surplus on the tooth surface was wiped away using a cotton roll before light polymerization for 40 s. After light curing the resin infiltrate was reapplied and the material was made to sit for 1 min and light polymerized for 40 s to minimize enamel porosity.

Diode laser bleaching[9]

The patient and the operator were made to wear wavelength-specific safety glasses. The lesion was covered with laser-activated bleaching gel of 1.5-mm thickness. Diode laser was then radiated three times for 30 s with a time interval of 60 s each from a distance of 2 mm at 1.5 w, 810 nm wavelength and using continuous mode. The bleaching agent was then made to remain on the tooth surface for 15 min. Later, the bleaching gel is wiped off, followed by irrigation with water to remove the bleaching gel completely. This cycle of applying the bleaching agent was repeated two more times. At the end of all three procedures, topical fluoride gel was applied to the maxillary and mandibular arches.

Esthetic improvement assessment[8]

Digital photographs of the patient's preoperative, postoperative, 1 month follow-up and 6 months follow-up were taken. The photographs were then evaluated using adobe Photoshop 7 software. The L*, a * and b * color space measurements for each photograph were noted. Where L * represents luminosity and the value ranges from 0 (black) to 100 (white) a * and b * represent the shade where a * is the measurement along the red-green axis and b * is the measurement along the yellow-blue axis. Esthetic durability was assessed by comparing L*, a * and b * values obtained from photographs taken immediately after treatment, 1 month, and 6 months to baseline data.

Color change was calculated using the following formula[8]



The color change obtained was then compared with the Baseline. Color difference (ΔE) more than 3.7 was considered clinically significant.[2]


  Results Top


The data obtained were collected, coded, and fed in SPSS (IBM version 23) for statistical analysis. The inferential statistics included the Kruskal–Wallis test and Friedman's ANOVA test. The level of significance was set at 0.05 at 95% confidence interval.

[Table 1] and [Graph 1] shows the mean distribution of esthetic improvement (ΔE) among different groups where resin infiltration showed an esthetic improvement (ΔE) of Mean ± standard deviation (SD) of 9.29 ± 6.41, 9.91 ± 4.03, and 15.64 ± 8.66 at T0, T1, and T6, respectively. Vital bleaching showed an esthetic improvement (ΔE) of Mean ± SD of 14.67 ± 12.51, 13.17 ± 8.90, and 17.87 ± 9.91 at T0, T1, and T6, respectively. Diode laser bleaching showed an esthetic improvement (ΔE) of Mean ± SD of 13.40 ± 10.99, 13.96 ± 7.30, and 16.47 ± 9.79 at T0, T1, and T6, respectively. The control group showed an esthetic improvement (ΔE) of mean ± SD 9.16 ± 7.12, 10.17 ± 6.63, and 14.19 ± 7.95 at T0, T1, and T6, respectively. The highest mean esthetic improvement (ΔE) was seen in the vital bleaching group.
Table 1: Mean distribution of esthetic improvement among different groups at different time intervals (immediately after treatment, after 1 month, and after 6 months)

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[Table 2] shows the Comparison of esthetic improvement (ΔE) between the different groups at time intervals of T0, T1, and T6. The resin infiltration group showed a mean rank of 27.73, 27.33, and 30.47 at T0, T1, and T2, respectively. Vital bleaching showed a mean rank of 34.03, 31.77, and 33.87 at T0, T1, and T2, respectively. Diode laser bleaching showed a mean rank of 33.5, 37.73, and 31.07 at T0, T1, and T2, respectively. The control group showed a mean rank of 26.73, 25.17, 26.6 at T0, T1, and T2, respectively. The Kruskal–Wallis test performed showed no statistically significant difference between the different treatment groups at different time intervals (P > 0.05).
Table 2: Comparison of esthetic improvement (ΔE) between the different groups at various time intervals

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[Table 3] shows the comparison of esthetic improvement (ΔE) between different time intervals T0, T1, and T6 among different groups. The resin infiltration group showed a mean rank of 1.53, 1.93, and 2.53 at T0, T1, and T2, respectively. Vital bleaching showed a mean rank of 1.87, 1.93, and 2.2 at T0, T1, and T2, respectively. Diode laser bleaching showed a mean rank of 1.73, 2.07, and 2.2 at T0, T1, and T2, respectively. The control group showed a mean rank of 1.6, 1.93, and 2.47 at T0, T1, and T2, respectively. Friedman's test showed statistically significant esthetic improvement (P = 0.022) for the different time intervals (immediately after treatment (T0), after 1 month (T1), and after 6 months) for the Resin infiltration technique. All the other techniques did not display a statistically significant change in color for the different time intervals (immediately after treatment (T0), after 1 month (T1), and after 6 months) (P > 0.05). [Graph 2] Distribution of change in Colour among different groups over a period of time.
Table 3: Comparison of esthetic improvement (ΔE) between different time intervals among different study groups

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  Discussion Top


Mild-to-moderate fluorosis is an unsightly disorder involving the maturation-phase enamel, where mainly the enamel surface layers are affected, and the main objective while treating such esthetically objectionable fluorotic lesions would be to preserve the tooth structure while simultaneously achieving a reasonably acceptable cosmetic result.[10] Several treatments have been devised to treat esthetically compromised lesions, which include vital bleaching, diode laser bleaching, and resin infiltration.[4],[5],[7] Thus the present in vivo study was conducted to compare and evaluate, the relative efficacy of vital bleaching with McInne's solution, 810 nm diode laser bleaching, and resin infiltration in the esthetic improvement of fluorosed teeth.

Sixteen children aged between 8 and 12 years with mild-to-moderate grade fluorosis as classified according to Modified Dean's fluorosis index and those who complained of objectionable esthetics were selected. Permanent incisors were selected in this study since the major determinant of the prevalence and severity of dental fluorosis was based on the fluoride exposure during the mineralization of permanent teeth. The earlier-forming teeth are more severely affected than the later-forming teeth thus incisors are most susceptible from 1 to 5½ years of age.[10],[11]

Each subject in the study had their central and lateral incisors being randomly assigned to the study groups which were Group A-Resin infiltration, Group B-vital bleaching, Group C-diode laser bleaching, and Group D-control group. This way the subject simultaneously acted both as the case as well as the control. This design of the study has an upper hand over the parallel study design and cross-over study design, requiring fewer study participants to obtain the same study power as the other study designs.[4]

In dentistry for assessment of esthetic changes, shade tabs are commonly used. In our study, however, CIE-L*, a*, b * colorimetry was used as it is deemed to be a more objective evaluation technique of recent times. This evaluation method has an advantage over the subjective shade tabs since the use of shade tabs is associated with a great variation in color perception among evaluators.[12] Furthermore, the color change (ΔE) makes it possible to assess objectively the esthetic improvement preoperatively and postoperatively as well as at different follow-up intervals. Under clinical conditions, a ΔE score of more than 3.7 is said to be detectable by the human eye. Assessment of esthetic improvement using (ΔE) score helps the evaluator to follow the evolution of color in each tooth thus making it a suitable evaluation technique for this study. A study done by Jarad et al. compared the observer's shade matching performance with the digital imaging method as done in our study to the conventional one. The results showed a statistically significant difference between the two methods with 43% and 61% correct match when using the conventional method and digital imaging method, respectively. Thus, their study concluded that digital cameras can be used as a means of color measurements in dental clinic.[12]

In the present study, the esthetic improvement was assessed for all the study groups immediately after the procedure, at 1-month interval, and at a 6 months interval. [Figure 1], [Figure 2], [Figure 3], [Figure 4] showing esthetic improvement posttreatment, where resin infiltration was done wrt 22, vital bleaching wrt 21, diode laser bleaching wrt 11. The mean value for immediate esthetic improvement for the vital bleaching group was found to be 14.67 which among the tested groups was the highest esthetic improvement postoperatively followed by the diode laser bleaching group, resin infiltration, and finally control group. The esthetic improvement obtained by the different study groups however was not statistically significant. Similar pattern of esthetic improvement was seen at the 1 month and 6 months follow-up. This study described the comparison of four different minimally invasive treatment techniques for the treatment of mild-to-moderate fluorotic lesions. It is difficult to compare the results of this study with data from the literature, as there are no published studies available where these four systems were compared with each other. Similar results were seen by Bharath et al. where vital bleaching showed better esthetic improvement when compared with enamel microabrasion in the treatment of fluorotic lesions.[5] A study done by Kiomars et al. where two different wavelengths of diode laser (810 and 980 nm) with two different hydrogen peroxide concentrations (30% and 46%) was compared with a control group being 40% hydrogen peroxide) with no light activation. The results of this study indicated that vital bleaching with 40% hydrogen peroxide had the highest mean value of shade change (ΔE) which is in agreement with the results of our study.[13] A study was done by Gugnani et al. using bleaching with 35% hydrogen peroxide, resin infiltration, resin infiltration with increased infiltration time, and a combination approach of bleaching and infiltration to treat non pitted fluorotic stains. The results of the study showed that better esthetic improvement was seen when resin infiltration with increased infiltration time was used as opposed to our study.[6]
Figure 1: Preoperative photograph

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Figure 2: Immediately postoperative

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Figure 3: One month postoperative

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Figure 4: 6 month follow up

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Improvement of esthetics was seen with regard to the resin infiltration group at different time intervals which are attributed to blending of enamel lesions, with the surrounding sound enamel, based on changes in the refractive index which is in accordance with a study done by Gugnani in 2014.[14] Statistically significant esthetic improvement was seen between immediate postoperative results (T0) and at 6 months follow-up (T6) this could be explained due to the absorption of water by the resin, which is not completely removed by the alcohol. This absorption can lead to a reduction in optical interfaces in the light path leading to improved esthetics over time. Our findings were in agreement with the study done by Cocco et al. where resin infiltration was used to treat fluorotic lesions who noted an improvement in esthetics over the course of time at 6 months follow-up.[15] Similar results were seen with regard to a study done by Garg and Chavda where resin infiltration was used to mask the white fluorotic lesions and the esthetic improvement was assessed using digital image analysis as done in our study. The authors concluded that resin infiltration maintained color stability and showed improvement of esthetics at the follow-up visits.[16]

There was an overall esthetic improvement with regard to vital bleaching and diode laser bleaching at the different follow-up intervals however Friedman's ANOVA did not show statistically significant results for the same. The observed improvement in esthetics over time is said to be due to subsequent rehydration of dental tissue and hypothesized neo-reaction of coloring molecules (previously oxidized during the bleaching process) reported by Lorenzo et al. in 1996.[17] Similar results were obtained by Abouelfotouh et al. where the color change and stability of in-office vital bleaching, home bleaching, and combination of both in-office and home bleaching were done.[18] A study done by Bacaksiz et al. was also in agreement with the findings obtained in our study. In this study, 2 commercially available vital bleaching kits were used Group 1 containing 25% hydrogen peroxide and Group 2 containing 36% hydrogen peroxide. The esthetic improvement (ΔE) was checked immediately after bleaching; 48 h; 1, 6, and 12 months later. In Group 2 at 6 and 12 months, significantly higher values of ΔE were observed compared to the baseline; which the authors quote is due to the gained oral hygiene habits, saliva composition and to the higher concentration of hydrogen peroxide used.[19] In the study done by Bharath et al., there was a reduction in esthetic improvement in the bleaching group at 6 months as opposed to the findings in our study however the findings were not statistically significant.[4]

This study is the first study to quantitatively measure the improvement in the esthetics of fluorosed teeth after resin infiltration, diode laser bleaching, and vital bleaching. Most reports of the literature are either individual case reports, and few studies have also separately measured the esthetic improvement of the different techniques used in this study. However, none of the studies till date have compared all the 3 well-known techniques of treating fluorosed teeth in vivo. This study has made an attempt to compare the three procedures and to record the long-term effects of these techniques.


  Conclusion Top


Within the limitations of the study, it can be concluded that all the three treatment measures showed good esthetic results with vital bleaching showing better results when compared to other study groups.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Photographs showing esthetic improvement of fluorotic lesions posttreatment.

Treatment done: Resin infiltration wrt 22, vital bleaching wrt 21, diode laser bleaching wrt 11, control group wrt 12



 
  References Top

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O'Mullane DM, Baez RJ, Jones S, Lennon MA, Petersen PE, Rugg-Gunn AJ, et al. Fluoride and oral health. Community Dent Health 2016;33:69-99.  Back to cited text no. 1
    
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Akpata ES. Occurrence and management of dental fluorosis. Int Dent J 2001;51:325-33.  Back to cited text no. 2
    
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Meireles SS, Goettems ML, Castro KS, Sampaio FC, Demarco FF. Dental fluorosis treatment can improve the individuals' OHRQoL? Results from a randomized clinical trial. Braz Dent J 2018;29:109-16.  Back to cited text no. 3
    
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Bharath KP, Subba Reddy VV, Poornima P, Revathy V, Kambalimath HV, Karthik B. Comparison of relative efficacy of two techniques of enamel stain removal on fluorosed teeth. An in vivo study. J Clin Pediatr Dent 2014;38:207-13.  Back to cited text no. 4
    
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Mariam R, Mathews M, Sudeep S, Dinesh N. Clinical evaluation of laser bleaching vs. conventional in-office bleaching. J Dent Lasers 2013;7:54-8.  Back to cited text no. 5
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Gugnani N, Pandit IK, Gupta M, Gugnani S, Soni S, Goyal V. Comparative evaluation of esthetic changes in non pitted fluorosis stains when treated with resin infiltration, in-office bleaching, and combination therapies. J Esthet Restor Dent 2017;29:317-24.  Back to cited text no. 6
    
7.
Muñoz MA, Arana-Gordillo LA, Gomes GM, Gomes OM, Bombarda NH, Reis A, et al. Alternative esthetic management of fluorosis and hypoplasia stains: Blending effect obtained with resin infiltration techniques. J Esthet Restor Dent 2013;25:32-9.  Back to cited text no. 7
    
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Gupta A, Dhingra R, Chaudhuri P, Gupta A. A comparison of various minimally invasive techniques for the removal of dental fluorosis stains in children. J Indian Soc Pedod Prev Dent 2017;35:260-8.  Back to cited text no. 8
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Azarbayjani Z, Jafarzadeh Kashi TS, Erfan Y, Chiniforush N, Rakhshan V. Efficacy of diode laser irradiation during dental bleaching in preventing enamel damage caused by bleaching. Dent Res J (Isfahan) 2018;15:320-6.  Back to cited text no. 9
    
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Ishii T, Suckling G. The appearance of tooth enamel in children ingesting water with a high fluoride content for a limited period during early tooth development. J Dent Res 1986;65:974-7.  Back to cited text no. 10
    
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Kihn PW. Vital tooth whitening. Dent Clin North Am 2007;51:319-31, viii.  Back to cited text no. 11
    
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Jarad FD, Russell MD, Moss BW. The use of digital imaging for colour matching and communication in restorative dentistry. Br Dent J 2005;199:43-9.  Back to cited text no. 12
    
13.
Kiomars N, Azarpour P, Mirzaei M, Hashemi Kamangar SS, Kharazifard MJ, Chiniforush N. Evaluation of the diode laser (810nm, 980 nm) on color change of teeth after external bleaching. Laser Ther 2016;25:267-72.  Back to cited text no. 13
    
14.
Gugnani N, Pandit IK, Goyal V, Gugnani S, Sharma J, Dogra S. Esthetic improvement of white spot lesions and non-pitted fluorosis using resin infiltration technique: Series of four clinical cases. J Indian Soc Pedod Prev Dent 2014;32:176-80.  Back to cited text no. 14
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Cocco AR, Lund RG, Torre E, Martos J. Treatment of fluorosis spots using a resin infiltration technique: 14-month follow-up. Oper Dent 2016;41:357-62.  Back to cited text no. 15
    
16.
Garg SA, Chavda SM. Color masking white fluorotic spots by resin infiltration and its quantitation by computerized photographic analysis: A 12-month follow-up study. Oper Dent 2020;45:1-9.  Back to cited text no. 16
    
17.
Shanbhag R, Veena R, Nanjannawar G, Patil J, Hugar S, Vagrali H. Use of clinical bleaching with 35% hydrogen peroxide in esthetic improvement of fluorotic human incisors in vivo. J Contemp Dent Pract 2013;14:208-16.  Back to cited text no. 17
    
18.
Abouelfotouh IF, Fahmy OM, Khairy AE, Salah Eldine DM. A comparative study of different bleaching techniques, regarding the color change, stability and postoperative hypersensitivity: A randomized controlled clinical trial. Stomatol Dis Sci 2018;2:1-13.  Back to cited text no. 18
    
19.
Bacaksiz A, Tulunoglu O, Tulunoglu I. Efficacy and stability of two in-office bleaching agents in adolescents: 12 months follow-up. J Clin Pediatr Dent 2016;40:269-73.  Back to cited text no. 19
    


    Figures

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

  [Table 1], [Table 2], [Table 3]



 

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