Minimal Invasive Technique for the Esthetic Management of Dental Fluorosis.

Dental fluorosis is a severe dental extremity due to excess fluoride intake during enamel formation, resulting in color abnormalities and severe tooth defects on its surface. This dental condition leads to abnormal appearance ranging from mild white to dark brown, affecting the esthetic characteristics and personality of the patient that eventually lowers their self-confidence. Restoration procedures and tooth-whitening procedures are the well-appreciated treatment methods for treating this anomaly. The current clinical report illustrates the minimally invasive technique for esthetic management of dental fluorosis in a 27-year-old male affected by dental fluorosis. Clinical examination revealed dental fluorosis of class II spots according to Dean's classification of fluorosis severity. The treatment plan involves minimally invasive micro-abrasion, vital teeth bleaching, and resin infiltration technique for blending different microporous lesions, mild-to-moderate fluorosis, and hypoplasia stains. Copyright:

INTRODUCTION

Dental fluorosis is considered as a hypo-mineralization of enamel owing to excessive intake of fluoride during enamel formation, leading to mild white and opaque areas or accompanied by yellowish and dark brown discoloration along with surface porosities on the surface of the enamel.[1] The dental condition is said to cause pathological changes to ameloblasts that further obstruct the normal hydroxyapatite crystal formation.[2] Excessive fluoride absorption during enamel maturation harmfully disturbs cleavage and elimination of amelogenins.[3] Retention of water and proteins delays enamel crystal growth, subsequently changing the degree of subsurface porosities.[3] The more unadorned the fluorosis, the more deep-seated the enamel subsurface microporous zone. In fluorosed dentin of permanent teeth, interglobular dentin is improved along with the prominence of incremental lines of von Ebner.[4]

In its form, fluorosed enamel is categorized by white lines due to heightened perikymata or rod ends. The white lines may be merging in a few cases, while in others, there may be distinct white opaque zones with lines in between. The entire enamel surface looks chalky white and opaque in a few severe cases. Subsurface porosity in such teeth may attract extrinsic stains, leading to tooth discoloration.[5] The incidence is more in second permanent molar and premolars and the least in first permanent molar and mandibular incisors, usually seen more often in maxillary teeth than mandibular ones.[6]

CASE REPORT

A 27-year-old medically fit male patient came to the dental clinic seeking a minimally invasive approach to treat fluorosis and hypoplasia stains. He complained that his teeth exhibited chalky white and brown spots that significantly affected his personality and smile [Figures 1 and 2]. No relevant family medical was seen. He did not undergo any treatment previously to address the issue. Examinations revealed dental fluorosis of class II spots (Dean's classification of dental fluorosis severity).

Figure 1

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Figure 2

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CLINICAL MANAGEMENT

Keeping in view the patient's young age, more traditional treatment was provided rather than proposing conventional therapeutic approaches. The treatment consisted of a combinational approach of mega and micro-abrasion, tooth bleaching, followed by resin infiltration to prevent dental fluorosis.

MACRO-ABRASION AND MICRO-ABRASION

The treatment began with the meg-abrasion technique by using a high-speed handpiece with a 105-μm fine diamond fur to eliminate the enamel up to 200–400 μm. Next, medium and then fine abrasive discs were used to reshape the enamel's surface and eliminate the sharp angles of the enamel. The photopolymerizable resin dam was introduced along with a tiny portion of abrasive paste containing silicon carbamide microparticle paste and 6.6% hydrochloric acid. It was applied to the teeth to be treated. Then, the micro-abrasion process was performed using a specific rubber cup with minimum pressure for 120 s.

IN-OFFICE BLEACHING

The patient initially received in-office bleaching treatment in which a 0.5–1.0-mm-thick layer of 38% hydrogen peroxide was applied, known as Opalescent Boost (Ultradent Products), to the teeth's labial surfaces [Figure 3]. The purpose of performing this was to alleviate the dark brown color of the tooth. After approximately 20 min, a destabilizing agent, known as Fluorinated Protector (3M ESPE CLINPRO White Varnish, USA), was painted on the surface of the bleached teeth for approximately 5 min. After that, the agent was removed with suction and water rinsing. All the above steps were repeated three times per visit. After the in-office bleaching procedure, the patient's teeth were polished using abrasive discs and fluoride gel. Further, the patient was recommended casein phosphate amorphous calcium phosphate (CPP-ACP) product for 3 months.

Figure 3

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RESIN INFILTRATION

Resin infiltration therapy was started after 2 weeks of in-office bleaching. For this, a resin infiltration system was utilized as per the instructions of the manufacturer. The patient's labial surfaces were etched three times with Icon-Etch gel for 2 min. It was followed by rinsing with water and was further entirely dried with Icon-Dry. A sufficient amount of Icon infiltrant was applied to the teeth, treated, and incubated for 3 min. These were further light-cured at 600 mW/cm square for 40 s. For 1 min, reapplication of the Icon infiltrant was performed and then light-cured again. The excess of the material was removed, and the tooth's surface was polished with the polishing paste with the help of polishing cups.

The final assessment of the treatment was done after 1 week of completion of resin infiltration therapy. Both the dentist and the patient were satisfied with the treatment results, although a few undetectable hypocalcified white spots were still there. After the follow-up visit, the patient's teeth possessed an impressive esthetic appearance [Figures 4 and 5]. The final tooth surface index of Fluorosis was 1.

Figure 4

Postoperative intraoral frontal view photo with Photoshop filter.jpg

Figure 5

Postoperative intraoral frontal view photo.jpg

DISCUSSION

The enamel mineralization is disturbed by the excess consumption of fluoride that further inhibits the crystal growth of enamel apatite. It further interferes with the deterioration of enamel matrix proteins, resulting in whitish-brown enamel and degrading its structure.[7] Fluorosis severity depends mainly on the length of exposure duration and the timing of exposure. Recent studies have shown that in-office bleaching is the most effective method for the treatment of dental fluorosis or teeth with mild discoloration.[78] There exists a solid pathological enamel layer on the surface of the affected teeth that blocks the entry of bleaching agents deep inside the enamel layers. Thus, mega- and micro-abrasion techniques were first performed before the in-office bleaching and resin infiltration. The dissolution effects of HCl dissolves the over-mineralized enamel tissue up to 25–200 μm, which enables the bleaching gel to penetrate the enamel layers and get whitening effects.[8]

Various studies have reported that enamel becomes demineralized after bleaching with carbamide gel which can be observed as honeycomb-like pores under a scanning electron microscope.[8] A chalky appearance persists in the teeth affected by dental fluorosis because the honeycomb-like structures are filled with air, demonstrating a different refractive index compared to the enamel. Similarly, resin infiltration infiltrant penetrates to honeycomb-like structure in the enamel with the help of capillary forces demonstrate a different refractive index. It is the only reason that resin infiltration is recommended for the treatment. Various studies have reported that resin infiltration improves the chalky appearance of the affected teeth, hence improving the esthetic appearance. However, some in-vitro studies demonstrate that resin infiltration-treated demineralized teeth often lack color stability and are more prone to staining, but the use of the polishing technique can significantly reduce the color change.[78]

Considering the viewpoint of various researchers, it has been envisaged that enamel micro-abrasion eliminates the stained tooth structure having subsurface porosities and fixes the appearance of the tooth with the help of abrasive HCl paste.[9] In the post-micro-abrasion procedure, the layer on the surface gets converted into an exceptionally polished and thoroughly compact mineralized structure. However, studies have failed to discover the precise mechanism involved in the enamel microabrasion technique through which the surface structure of teeth improves. In context to this, researchers proposed two statements concerning the organic material and mineralized tooth getting dissolved with the acidic components and micro-abrasive surfaces refract and reflect the light from teeth to mask discolorations of the enamel. Although an enormous number of studies have been performed on microabrasion involving case studies and clinical trials, much more detailed analysis is still required to investigate the mechanisms. A well-defined clinical study revealed that the technique nearly removes all the brown coloration, whereas the elimination percentage of white stain is approximately 60%–100%.[9]

Another clinical trial reported that enamel microabrasion along with HCl-pumice paste results in a score of 5.38 in appearance improvement and 5.06 for removal of stains, as detected by VAS ranging 1–7.[10] Similarly, another study revealed scores of 3.4 and 2.4 for appearance improvement with the help of specific products used for micro-abrasion of enamel.[11] The results in the current report, however, are similar to previous studies. Thus, the enamel microabrasion and in-office bleaching technique prove useful for esthetic appearance as it removes all the brown stains and harmonizes the color of the teeth while depicting the light and homogenous structure of teeth. Previous studies have also demonstrated the same results with the combination of in-office bleaching, micro-abrasion, and resin infiltration techniques.[12] Quite inconsistent results concerning in-office bleaching and resin infiltration have been revealed by various studies in severe dental fluorosis.[7] One of the studies applied enamel microabrasion and home-bleaching techniques for severe dental fluorosis and recommended this minimally invasive procedure for its treatment.[78]

CONCLUSION

Bleaching with resin infiltration is considered a conservative treatment approach for cases of fluorosis. Minimal invasive procedures are preferred to preserve more of the vital tooth structure and serve better with long-term follow-up. The current study proposed a minimally invasive technique involving microabrasion, in-office bleaching, and resin infiltration as a productive technique for treating dental fluorosis. Enamel microabrasion proved beneficial for improving the appearance of affected teeth.

Further in-office bleaching and resin infiltration removed the brown and white stains while producing a shiny white structure, promoting an esthetic appearance. The results of the current study are similar to those of previous studies. Thus, the minimally invasive technique involving microabrasion and in-office bleaching followed by resin infiltration can be recommended as a first-line treatment for mild to moderate to severe dental fluorosis. The study forms a base for future research on esthetic dental sciences and minimally invasive treatment for dental fluorosis by providing an evidence-based review of previous research on dental fluorosis. However, the current study could not explore the mechanisms involved in micro-abrasion of affected teeth. Future research should focus on actual mechanisms involved in micro-abrasions, in-office bleaching, and resin infiltration.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.