Microabrasion in Aesthetic Management of Dental Fluorosis Stains

Effectiveness of Microabrasion Procedure for Aesthetic Management of Dental Fluorosis Stains

Dr Mayada Jemâa ¹
Dr S. Lakhal ²
Dr H. Brahem ¹
Pr N. Zokkar ³
Pr L. Bhouri ³
Pr S. Marouen ⁴ 
Pr MB. Khattech ⁴

¹ Assistant Professor, Department of Dental Medicine, Military Principal Hospital of Instruction, Tunis, Tunisia
² Resident, Department of Dental Medicine, Military Principal Hospital of Instruction, Tunis, Tunisia
² Resident, Department of Dental Medicine, Military Principal Hospital of Instruction, Tunis, Tunisia
⁴ Professor, Department of Dental Medicine, Military Principal Hospital of Instruction, Tunis, Tunisia

Dental News Magazine June 2019 Issue

Abstract 

The excessive systemic absorption of fluoride during the tooth development will cause dental fluorosis which is the most common type of enamel demineralization. ¹ This kind of pathology leads to the whitish, opaque and unpleasant appearance of enamel that is often visible. ²                                                                                                    

Dental fluorosis may induce psychosocial effects on patients and affect their quality of life. ³ In the literature, different treatment modalities to manage dental fluorosis were described. The treatment depends on the
severity of the fluorosis ranging from ceramic veneers to composite restorations and chemo-mechanical procedure. ²                                                                                                                                      

Recently, enamel microabrasion has been proposed as a safe, effective, economic, conservative, minimally invasive, non-restorative and less time-consuming method that improves the esthetic aspect of teeth with fluorosis.                                                                                       Added to that, surface enamel modifications (roughness and microhardness) resulting from microabrasion, are easily restored by saliva. ⁴ 

Hence, the objectives of this article are:

–  To define the dental fluorosis

– To describe the microabrasion method:
Step by step

– To discuss the effects of microabrasion technique on the enamel surface.

– To report three clinical cases suffering from moderate dental fluorosis treated in our service of Dental Medicine with enamel microabrasion procedure.  

Key Words: Enamel microabrasion, fluorosis, tooth discoloration, remineralization, esthetics, minimally invasive treatment.

Introduction

During tooth development, the excessive systemic absorption of fluoride can result in dental fluorosis. ^{5, 1, 3} Dean et al. in 1940 have demonstrated that there is a relation between the concentration of fluoride in drinking water and the prevalence and the gravity of dental fluorosis. ⁶

Referring to Danielson Guedes Pontes et al. 2012, the dental fluorosis is the result of chronic fluoride intoxication caused by excess ingestion going beyond tolerable limits for a prolonged period. ⁷ Bilateral, diffuse, thin and horizontal white striations and stained plaque areas are present. Then, depending on the severity of the dental fluorosis, the affected enamel may become discolored and/or pitted. ^{3, 4}                                                               

The severity of dental fluorosis depends on three factors: quantity of ingested fluoride, exposure duration and the stage of tooth development during fluoride ingestion. ⁷

Dentists have to diagnose fluorosis correctly and choose the appropriate treatment plan because of its important incidence. ¹ Opaque white areas or discolorations ranging from yellow to dark brown, together with porosities on the enamel surface, characterize dental fluorosis. ^{4, 8} This pathology is one of the most common types of enamel demineralization. ^{1, 9}

Dental fluorosis has a psychological impact on patients because of the unaesthetic affected anterior teeth. ⁸                                                                                                        

Referring to literature, teeth discolored by fluorosis may be managed by porcelain laminate veneers, crowns or resin composite restorations. However, all these techniques are considered invasive. ⁷

Generally, most patients demanding treatments for fluorosis are young adults and the invasive prosthetic treatment options (veneers, crowns) are not recommended because of the excessive sacrifice of tooth structure, the high cost and the more time consuming.^6,10Referring to the International Symposium on Non-Restorative Treatment of Discolored Teeth, the microabrasion technique is described as a safe, conservative and effective atraumatic procedure to eliminate the superficial enamel stains caused for example by fluorosis. ⁵                                                                                                                                              

Different publications reported patient satisfaction after using microabrasion procedure alone and considering it as a safe, effective and simple technique to manage fluorosis stains mainly located in esthetic areas. ⁸

Indices to measure dental fluorosis ^{1, 23} 

Different indices have been proposed to measure dental fluorosis like Dean‘s index, The Community Fluorosis Index (1946), Thylstrup-Fejerskov index, Total Surface Index of Fluorosis, Fluorosis Risk Index, Developmental defects of enamel Index.                                                                                                                                        

Nowadays, new concepts in measurement of Dental Fluorosis exist such as visual analogue scale (VAS) by Vieira et al. 2005, Quantitative Light Fluorescence by Pretty et al. 2006 and Quantitative Light Fluorescence and Polarised white light Images by Pretty et al. 2012.

In our clinical cases we used Dean‘s index: (Table 1)                                                             

First, this index was proposed in 1934 and in 1942, it was modified. It classifies dental fluorosis on a 6-point ordinal scale. 

Microabrasion technique

Referring to Pini et al.  2015, enamel microabrasion should be the first option to manage teeth with intrinsic stains because it eliminates opaque, brown colorations and surface irregularities by offering a more regular and lustrous surface. ⁴                                    

After microabrasion, the surface can be considered more caries resistant compared with the initial surface. ¹                                                                                                                                               First, Dr. Walter Kane (Colorado Springs, 1916) proposed this procedure. It consists of the use of mild acid combined with rotary application of an abrasive medium.¹                                                                                                                                 

McCloskey in 1984 proposed the use of acid combined with pumice to manage dental fluorosis. After two years, Croll called this technique “microabrasion”. ¹ The microabrasion procedure requires the use of hydrochloric acid mixed with an abrasive powder (combination of erosion and abrasion). After this procedure, the surface has a glass-like lustre aspect because of the presence of dense prismless layer that was formed on the abraded enamel surface. ¹¹

Croll and Cavanaugh removed white enamel opacities by means of a wooden stick and firm finger pressure for 5 seconds of application of hydrochloric acid (18%) and pumice. Not surpassing 15 applications. After each application, the treated enamel was washed and dried. ^{5, 12}

Actually, this technique is no longer relevant because the use of an important concentration of hydrochloric acid in the mouth is dangerous (caustic potential of 18 % HCl). ^{5, 3}                                                                                                                                  Recently, other secure highly safe and efficient microabrasion products were developed and were commercially available such as Prema compound (Premier Dental Products), Opalustre (Ultradent), Whiteness RM (FGM).

Prema Compound, Opalustre and Whiteness RM contain a mild concentration of hydrochloric acid (10%, 6% and 6% respectively) and a fine-grit silicon carbide abrasive in a water-soluble gel. The microabrasion product is applied in a little quantity on the fluorosis stains or on the surface irregularities.  

For Prema Compound product, it is recommended to use synthetic rubber tips, a rotary mandrel and 10: 1 gear reduction angle at 30-second intervals. For the Opalustre product, dentists should use a rubber cup with a 10:1 gear reduction angle at 1-minute intervals. Regular rinse by means of water spray is necessary between the different applications of the microabrasion product. The last step is to rinse, dry and polish the surface. We can also use a gel containing 2% of neutral sodium fluoride to apply on the enamel surface for 4 minutes. ¹²  Referring to Sundfeld et al. 2007, the quantity of eliminated enamel by microabrasion procedure is not pertinent. ¹²

Referring to Celik et al. 2013, the microabrasive technique just removes the outer enamel surface (10–200 μm);                                                                                                                                         Although different publications recommend the use of microabrasion procedure alone to treat dental fluorosis, other studies advocate the combination of enamel microabrasion with vital bleaching and composite restorations to manage tooth discoloration. 

The aim of this combination is that microabrasion technique used alone cannot offer excellent results. ⁸ The success of enamel microabrasion is related to the depth of enamel alteration. ¹³

When the severity of dental fluorosis increases, it is hard to eliminate deep intrinsic stains and porosities by only microabrasion method. ⁸

Better esthetic results with microabrasion technique are achieved for surface stains than deeper ones. ¹⁴                                                                                                   After enamel microabrasion, the color of treated teeth may become darker or more yellow because of the thinner enamel and the color of dentin will be more evident like the color observed in the cervical third of crown or like teeth ageing. ^{13, 15}

Indications of Enamel Microabrasion ⁴

– Stains or defects limited only to enamel surface,

– Dental fluorosis,

– Reparation of surface irregularities (imperfect enamel formation, surface irregularities caused by removal of residual resin composite from orthodontic brackets with diamond burs…),

– Mineralized white stains,                                                                                                                                       

– Localized or idiopathic enamel hypoplasia limited to the outer enamel layer,

– Polishing of enamel and helping to remove composite resin residues after orthodontic treatment.

Limits of Enamel Microabrasion ^{2, 4, 12}

The age of the patient is not pertinent for such procedure. Some limitations of this technique are mentioned such as the difficult use of rubber dam when teeth are not completely erupted, deficient lip sealing (risk of development of a moisturizing pellicle on enamel in absence of upper and lower lips protection) and also dentin located stains.                                                                                                                      

In case of deficient lip sealing, following orthodontic treatment and/or speech therapy is the first recommended option before enamel microabrasion.                                                                                 

Referring to Benbachir et al. 2007, enamel microabrasion is not recommended for amelogenesis imperfecta that presents deep lesions. ¹⁶

Referring to Ardu et al. 2009, although enamel microabrasion is cheaper than prosthetic treatment it is considered costly because of the important chair time when dental fluorosis is medium or severe and the procedure must be repeated frequently to acquire the acceptable result.

Examples of microabrasion products that are commercially available (Table 2) ^{4, 5, 14}

Some studies suggest replacing hydrochloric acid with 37% phosphoric acid in microabrasion method. The phosphoric acid is useful in such procedure for two reasons:  it is frequently used in clinical practice for other procedures (bonding…) and it generates less enamel surface damages (less enamel loss) compared with HCL. ^{3, 4, 15}

Referring to Sundfeld et al. 2014, the 37% phosphoric acid was combined with extra fine grain pumice in equal volume proportions in microabrasion method. ¹⁷                                                                                                                                            A study of Bassir et al. 2013 comparing clinical efficiency of phosphoric acid- pumice compound with conventional hydrochloric acid- pumice compound in treating different severities of dental fluorosis with the microabrasion technique concluded that the phosphoric acid- pumice compound improved aesthetic indices in fluorotic teeth similar to the HCl-pumice compound. ⁹

Referring to Fragoso et al. 2011, the combination of 30-40% of phosphoric acid and pumice is indicated to eliminate the white spots resulting from inactive surface decalcifications because of the ineffective teeth cleaning during orthodontic therapy. ¹⁴                                                                                                                        

A study of Sheoran et al. 2014 evaluating the effectiveness of two microabrasion products (37% phosphoric acid and 18% hydrochloric acid) for the removal of developmental enamel opacities in young permanent maxillary incisors showed that both microabrasion procedures revealed comparative highly significant successful outcome in esthetic clinical treatment of enamel opacities and in terms of subject’s satisfaction. ¹⁸

Effects of microabrasion procedure on enamel surface

An in-vitro study of Bertoldo et al. 2014 evaluated the enamel roughness after microabrasion (37% phosphoric acid and pumice, Opalustre) followed by different polishing methods. The conclusion was that all enamel microabrasion products increased enamel roughness and the efficiency of the polishing systems was dependent upon the abrasive employed. ¹⁹
A study of Fragoso et al. 2011 evaluated the effect of microabrasion (37% phosphoric acid and pumice, Opalustre, Whiteness RM) and polishing on the microhardness and roughness of bovine enamel, and the effect of artificial saliva on the hardness of enamel. The conclusion was that enamel microabrasion followed by polishing generated higher hardness and better enamel surface smoothness. Although, enamel hardness was not increased by its immersion in artificial saliva. ¹⁴                                                                                                                

Referring to Pini et al. 2015, enamel surface roughness is increased by microabrasion procedure nevertheless (6.6 %) hydrochloric acid or (18% or 35%) phosphoric acid with abrasive was employed. Added to that, enamel roughness and hardness can be inverted by polishing technique or the exposure to saliva. ⁴ 

A study of Pini et al. 2016 evaluating the effect of saliva on enamel after microabrasion procedure (35% phosphoric acid and pumice,  6.6% hydrochloric acid (HCl) and silica) with different microabrasive compounds under in situ conditions concluded that saliva was effective in promoting the rehardening of enamel after microabrasion procedure, essentially for the surfaces treated with HCl and silica. ²⁰                                                                          

An in vitro study of Rodrigues et al. 2013 evaluated the in vitro changes on the enamel surface after a microabrasion procedure realized by different products (silicon polisher, 37% phosphoric acid and pumice stone, Micropol, Opalustre,   Whiteness RM). The conclusion was that despite enamel microabrasion was described as a conservative treatment regardless of the type of the microabrasive agent used, the products used in the study revealed minor roughness alterations and minimal wear. Added to that, the use of phosphoric acid and pumice stone presented similar results to commercial microabrasive products concerning the surface roughness and wear. ²¹

Tooth bleaching associated to enamel Microabrasion

After microabrasion procedure, dentists can accomplish bleaching to mask remnants of white spot lesions and to enhance the results of the enamel microabrasion (uniform tooth shade). ^{2, 3, 7, 10} The combination of microabrasion and dental bleaching offers excellent esthetic results and patient acceptance. Both methods are conservative, painless, fast and easy to perform. ^{7, 16}

At- home bleaching contributes to the assimilation of the color of the fluorotic stains with the color of the remaining enamel surface. Moreover, in-office bleaching did not affect the color and the luminosity of the fluorotic teeth. ³

Referring to Sundfeld et al. 2007, teeth treated with microabrasion procedure can obtain a yellowish or darker coloration after this treatment. To resolve this esthetic problem, it is recommended to achieve dental bleaching (hydrogen peroxide gel in a polyethylene strip system or bleaching topical application with carbamide peroxide gel in custom-formed soft vinyl mouth trays). The concentrations of carbamide peroxide can be 10%, 15% or 16%. ¹² A study of Franco et al. 2016 evaluating the effects of the association of microabrasion and dental bleaching on the physical properties of enamel concluded that dental bleaching does not cause important damage to microabraided enamel, and that just human saliva recovered the initial enamel microhardness. Therefore, the immediate or late association of dental bleaching with enamel microabrasion will not lead to a negative influence on the surface roughness or hardness of enamel. ²² A study of Perete-de-Freitas et al. 2017 evaluating the effect of prior microabrasion procedure on the teeth color
modification and teeth bleaching efficiency concluded that although microabrasion procedure have changed tooth color, it did not affect the final results obtained with tooth bleaching using an important concentration of hydrogen peroxide. ¹³

Clinical cases

Case report N°1

A 22- year old girl looked for dental therapy to remove and/or minimize the noticeable brown/yellow staining on the buccal surfaces (incisal third) of her teeth (11 and 21).

Diagnosis: Mild fluorosis staining determined by using Dean’s Fluorosis Index (Table 1). A treatment plan (minimally invasive) was presented to the patient: Microabrasion of the superficial enamel with Opalustre (Ultradent).

Case report N°2

A 25- year old girl looked for cosmetic treatment for her teeth that presented white and brown stains. 

Diagnosis:  Mild fluorosis staining referring to Dean’s Fluorosis Index (Table 1). Treatment proposed: Enamel Microabrasion technique with Whiteness RM (FGM).

Case report N°3

A 30- year old girl consulted with a chief complaint about the appearance of her front teeth that present white and brown stains.  

Diagnosis:  Mild fluorosis staining referring to Dean’s Fluorosis Index (Table 1). The treatment plan presented to the patient included enamel Microabrasion by means of Whiteness RM (FGM).

Conclusion

The results of our clinical cases suffering from mild dental fluorosis treated with only microabrasion procedure showed improvement in appearance of discolored teeth and patient‘s satisfaction.                                                                                                                     

In case of moderate-severe fluorosis, the association of enamel microabrasion and dental bleaching is advisable to optimize the esthetic result. 

After microabrasion method, it is recommended to polish the enamel surface and eventually to apply a desensitizing paste based on fluoride and/or CPP-ACP for 5 to 15 minutes. This minimal invasive atraumatic and safe approach forthe elimination of superficial enamel stains and defects offers favourable aesthetic permanent results and re-establish patient’s self-esteem.

References

1. Balan B, Madanda Uthaiah C, Narayanan S, Mookalamada Monnappa P. Microabrasion: an effective method for improvement of esthetics in dentistry. Case reports in dentistry. 2013;2013:951589. 2. Ardu S, Benbachir N, Stavridakis M, Dietschi D, Krejci I, Feilzer A. A combined chemo-mechanical approach for aesthetic management of superficial enamel defects. British dental journal. 2009;206(4):205-8. 3. Castro KS, Ferreira AC, Duarte RM, Sampaio FC, Meireles SS. Acceptability, efficacy and safety of two treatment protocols for dental fluorosis: a randomized clinical trial. Journal of dentistry. 2014;42(8):938-44. 4. Pini NI, Sundfeld-Neto D, Aguiar FH, Sundfeld RH, Martins LR, Lovadino JR, et al. Enamel microabrasion: An overview of clinical and scientific considerations. World journal of clinical cases. 2015;3(1):34-41. 5. Loguercio AD, Correia LD, Zago C, Tagliari D, Neumann E, Gomes OM, et al. Clinical effectiveness of two microabrasion materials for the removal of enamel fluorosis stains. Operative dentistry. 2007;32(6):531-8. 6. Ardu S, Stavridakis M, Krejci I. A minimally invasive treatment of severe dental fluorosis. Quintessence international (Berlin, Germany : 1985). 2007;38(6):455-8. 7. Pontes DG, Correa KM, Cohen-Carneiro F. Re-establishing esthetics of fluorosis-stained teeth using enamel microabrasion and dental bleaching techniques. The European journal of esthetic dentistry : official journal of the European Academy of Esthetic Dentistry. 2012;7(2):130-7. 8. Celik EU, Yildiz G, Yazkan B. clinical evaluation of enamel microabrasion for the aesthetic management of mild-to-severe dental fluorosis. Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry  [et al]. 2013;25(6):422-30. 9. Bassir MM, Bagheri G. Comparison between phosphoric acid and hydrochloric acid in microabrasion technique for the treatment of dental fluorosis. Journal of conservative dentistry : JCD. 2013;16(1):41-4. 10. Romero MF, Babb CS, Delash J, Brackett WW. Minimally invasive esthetic improvement in a patient with dental fluorosis by using microabrasion and bleaching: A clinical report. The Journal of prosthetic dentistry. 2018;120(3):323-6. 11. Wong FS, Winter GB. Effectiveness of microabrasion technique for improvement of dental aesthetics. British dental journal. 2002;193(3):155-8. 12. Sundfeld RH, Croll TP, Briso AL, de Alexandre RS, Sundfeld Neto D. Considerations about enamel microabrasion after 18 years. American journal of dentistry. 2007;20(2):67-72. 13. Perete-de-Freitas CE, Silva PD, Faria ESAL. Impact of Microabrasion on the Effectiveness of Tooth Bleaching. Brazilian dental journal. 2017;28(5):612-7. 14. Fragoso LS, Lima DA, de Alexandre RS, Bertoldo CE, Aguiar FH, Lovadino JR. Evaluation of physical properties of enamel after microabrasion, polishing, and storage in artificial saliva. Biomedical materials (Bristol, England). 2011;6(3):035001. 15. Sundfeld D, Pavani CC, Schott TC, Machado LS, Pini NIP, Bertoz APM, et al. Dental bleaching on teeth submitted to enamel microabrasion 30 years ago-a case report of patients’ compliance during bleaching treatment. Clinical oral investigations. 2018. 16. Benbachir N, Ardu S, Krejci I. Indications and limits of the microabrasion technique. Quintessence international (Berlin, Germany : 1985). 2007;38(10):811-5. 17. Sundfeld RH, Sundfeld-Neto D, Machado LS, Franco LM, Fagundes TC, Briso AL. Microabrasion in tooth enamel discoloration defects: three cases with long-term follow-ups. Journal of applied oral science : revista FOB. 2014;22(4):347-54. 18. Sheoran N, Garg S, Damle SG, Dhindsa A, Opal S, Gupta S. Esthetic management of developmental enamel opacities in young permanent maxillary incisors with two microabrasion techniques–a split mouth study. Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry  [et al]. 2014;26(5):345-52. 19. Bertoldo C, Lima D, Fragoso L, Ambrosano G, Aguiar F, Lovadino J. Evaluation of the effect of different methods of microabrasion and polishing on surface roughness of dental enamel. Indian journal of dental research : official publication of Indian Society for Dental Research. 2014;25(3):290-3. 20. Pini NIP, Lima D, Sundfeld RH, Ambrosano GMB, Aguiar FHB, Lovadino JR. Tooth enamel properties and morphology after microabrasion: an in situ study. Journal of investigative and clinical dentistry. 2016;8(2). 21. Rodrigues MC, Mondelli RF, Oliveira GU, Franco EB, Baseggio W, Wang L. Minimal alterations on the enamel surface by micro-abrasion: in vitro roughness and wear assessments. Journal of applied oral science : revista FOB. 2013;21(2):112-7. 22. Franco LM, Machado LS, Salomao FM, Dos Santos PH, Briso AL, Sundfeld RH. Surface effects after a combination of dental bleaching and enamel microabrasion: An in vitro and in situ study. Dental materials journal. 2016;35(1):13-20. 23. Funmilayo A.S.M, Mojirade A.D. Dental Fluorosis and its Indices, what’s new?. Journal of Dental and Medical Sciences 2014; 13(7): 55-60.