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that forces of do exert cervical flexural strain, which lends credence to Esthetic and Predictable the theory of abfraction. If this cervical enamel area has suffered additional ex- posure from gingival recession, as well Treatment of Abfraction Lesions as a reduction in thickness secondary to toothpaste , the development This type of lesion is common in today’s patient population, opening up a new avenue of an abfraction lesion may be acceler- of restorative treatment. ated.6 To what extent toothpaste abra- By Robert Marus, DDS sion and gingival recession contribute to the genesis of the abfraction lesion is unclear, but they may act as abfrac- tion initiators and/or enhancers, thus s our population material (retentive failure). This fail- The etiology of the abfraction le- starting the process.7 As these cervical e x p e r i e n c e s ure can create a practice-management sion appears to be multifactorial in enamel rods flake away, is ex- greater longevity, issue if patients are repeatedly return- nature,3 and off-axis occlusal forces posed and the dentin continues to re- dental treatment ing for follow-up visits to replace failed transmitted through the tooth can be ceive the focused flexural stress creating that allows pa- restorations. This common failure adds a contributing factor.4 This occlusal the telltale V- or wedge-shaped pattern tients to main- to the reluctance of the practitioner to force may be intensified by hyperoc- (Figure 1 and Figure 2). In some cases, tain their natural treat abfractions, and may promote clusion, clenching, and . As formation of an extremely sharp line dentition is more critical than ever. the philosophy that abfractions are not teeth bear the occlusal load, the shell angle at the apex of the lesion occurs. AWith increased longevity, the dentition worth treating. Because clinicians are of the enamel flexes under the strain. This pattern is highly suggestive of a fo- is considerably more exposed to wear naturally reluctant to perform more The compressive force of occlusion be- cusing of force, as in a bending moment. from decades of use. Abfraction lesions, aggressive treatment such as full cov- comes focused as a sheering force in the In other cases, a more smooth concave also referred to as non-carious cervical erage, the lesion often goes untreated. region of the CEJ. This area of enamel is lesion has developed, which suggests lesions, on the facial and sometimes Additionally, treatment options us- most vulnerable to delamination from that toothpaste abrasion had a more lingual surfaces of teeth are seen with ing periodontal regenerative therapy the underlying supporting dentin be- prominent role in etiology. greater frequency as our population should be explored at the time of diag- cause the enamel shell progresses to a The fact that abfraction lesions de- ages. This article addresses how to treat nosis. Note that restorative treatment of thin “feather-edge” of enamel rods or velop predominantly on the facial or the pattern of destruction in abfraction these lesions with composite does not prisms. That fact that many Class V buccal surfaces of the tooth suggest lesions.Treatment of abfraction lesions eliminate the possibility of periodontal restorations using conventional com- that gingival recession and toothpaste specifically using flowable composite regenerative treatment in the future. posite suffer retentive failure suggests abrasion be strong contributory factors preserves tooth structure in an esthetic, conservative, and predictable way. By definition, abfraction1 is a theory that is used to explain the loss of enamel and dentin from flexural occlusal forces, particularly at the cemento–enamel junction (CEJ). This theory postulates that occlusal forces cause the flex- ure of the crown of enamel, focusing load at the CEJ and, ultimately, caus- ing a separation of the enamel rods. fig. 1 fig. 3 fig. 5 Frequently, clinicians will leave these lesions untreated until these lesions become carious. For many clinicians, the treatment of abfraction lesions has been problematic.2 The most fre- quently cited failure has been the lack of retention of the composite restorative

Robert Marus, DDS Private Practice fig. 2 fig. 4 fig. 6 Yardley, Pennsylvania LESION FORMATION (1. and 2.) As RESTORATION (3. and 4.) The LESION REMOVAL (5.) Exposed enamel rods flake away, dentin is proximity of the curing light during dentin from an abfraction lesion exposed and continues to receive placement of a Class V restoration on teeth Nos. 27 and 28. (6.) Caries the focused flexural stress, creating should be close enough to ensure was removed with a slow-speed the V- or wedge-shaped pattern. an adequate depth of cure. round bur and all sharp line angles were smoothed and beveled.

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in the development of this lesion.10 flowable composites, such as Venus® This author hypothesizes that gingi- Diamond Flow (Heraeus, www.her- val recession and toothbrush abrasion aeus-dental-usa.com), enables the may serve as abfraction lesion “initia- author to place this material in only tors” as well as “enhancers” that fa- two to three increments with improved cilitate the development and rate of marginal integrity. The low shrinkage progression of these lesions, with oc- stress of Venus Diamond Flow compos- clusal load as the initiating factor and ite, combined with the lower C-factor driving force behind the lesion.9 In the of a Class V restoration,15 may allow for author’s opinion, flowable composite’s bulk filling of this class of restoration. relative low modulus of elasticity (ie, The close proximity of the curing light Young’s modulus) makes it an ideal re- in a Class V restoration during place- storative material for treating abfrac- ment should ensure an adequate depth tion lesions. Its more flexible nature, as of cure regardless of shade (Figure 3 compared to traditional composite or and Figure 4). enamel itself, allows for the absorption or reduction of these occlusal flexural Case Presentation forces at the CEJ. It is this dissipation A 46-year-old man presented to the of the sheering force that allows the author’s office for his routine dental flowable composite Class V restoration hygiene visit, but had a chief complaint to resist displacement. In fact, restora- of cold sensitivity in the lower right tion of the lesion relieves concentrated quadrant. Physical and radiographic stress at the apex of the lesion, prevent- examination revealed that the source ing further abfraction.2 Additionally, of sensitivity was the presence of ex- the use of new “low shrinkage stress” posed dentin from an abfraction lesion

fig. 7 fig. 8

fig. 9 fig. 10

fig. 11 fig. 12

RESTORATION and final results(7.) The facial surfaces of the teeth were mechanically etched. (8.) The teeth were then acid-etched for 15 seconds and rinsed thoroughly. (9.) The bonding agent was placed, thinned, and dried thoroughly. (10.) Using a periodontal probe as a placement instrument, the flowable composite in shade opaque medium was applied to the preparation. (11.) Two additional increments of flow- able composite (shade A2) were placed in a similar fashion covering the cervical and middle thirds of the teeth. (12.) A thin layer of sealant was placed and light-cured for 20 seconds to serve as a final “clear coat” for the final restorations.

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on teeth Nos. 27 and 28 (Figure 5). yellow in hue. Local anesthetic was then may be compromised. By ending this in the near future.5,11,12 Abfraction lesions The patient was scheduled for opera- administered on teeth Nos. 27 and 28, restoration more occlusally, well into are common in today’s patient popula- tive treatment of these teeth. Venus and treatment initiated. Caries was ex- microetched enamel, additional bond tion, and the treatment of this type of Diamond Flow composite was selected cavated with a slow-speed round bur and strength could be obtained.8 lesion opens up a new avenue of restor- as the restorative material. all sharp line angles were smoothed and When the acid-etching was complete, ative treatment in today’s practice. beveled with a Brasseler 8856 fine-grit, the bonding agent was placed using Treatment round-end-taper, 30-µm bur (Brasseler iBOND® Total Etch (Heraeus), which References Whitening using Venus® White Pro USA, www.brasselerusa.com) (Figure was thinned and dried thoroughly 1. Grippo JO. Abfractions: A new classification 22% (Heraeus) was performed 1 month 6). Removing these line angles as well (Figure 9). Then, using a periodontal of hard tissue lesions of teeth. J Esthetic Dent before the restorative treatment. At the as the V-shaped pattern of the cervical probe as a placement instrument, Venus 1991;3(1):14-19. whitening-tray delivery appointment, lesion relieved concentrated stress at Diamond Flow flowable composite 2. Kuroe T, Itoh H, Caputo AA, Konuma M. teeth Nos. 27 and 28 were treated the apical area of the lesion.2 shade OM (shade opaque medium) was Biomechanics of cervical tooth structure lesions with Gluma® Desensitizer PowerGel The facial surfaces of the teeth were applied to the preparation (Figure 10). and their restoration. Quintessence Int. 2000; (Heraeus) to reduce the possibility of then mechanically etched with the It is important to re-create the dentin 31(4):267-274. any sensitivity during the whitening MicroEtcher II (Danville, www.dan- with a more opaque composite, because 3. Bernhardt O, Gesch D, Schwann C, et al. process. The patient was instructed villematerials.com) (Figure 7) and this is consistent with the anatomical Epidemiological evaluation of the multifac- to complete the whitening process at acid-etched with Ultra-Etch® 35% nature of the cervical area of the tooth.14 torial etiology of abfractions. J Oral Rehabil. least 2 weeks prior to the dental visit phosphoric acid (Ultradent Products, Two additional increments of Venus 2006;33(1):17-25. for the treatment of teeth Nos. 27 and www.ultradent.com) for 15 seconds and Diamond Flow (shade A2) were placed 4. Ceruti P, Menicucci G, Mariani GD, et al. 28 in order to allow the dentition to rinsed thoroughly (Figure 8). The use of in a similar fashion covering the cervical Non carious cervical lesions. A review. Minerva fully rehydrate. mechanical etching is very effective in and middle thirds of the teeth (Figure Stomatol. 2006;55(1-2):43-57. At the operative visit, the newly whit- providing a meticulously clean surface 11). Finishing at the 5. Schneider LF, Cavalcante LM, Silikis N. ened tooth shade was taken before anes- before acid-etching and bonding. Also, was performed with a Brasseler 8392 Shrinkage stresses generated during resin-com- thetizing the patient. Care was taken to because the dentin in an abfraction le- 30-µm gingival finishing bur, as any ex- posite applications: A review. J Dent Biomech. evaluate the shade at the cervical third sion is typically sclerosed, the ability cess composite at the gingival margin 2010;2010(131630). Epub 2009 Sep 30. of the teeth, which is typically more of restorative materials to bond well would promote gingival inflammation. 6. Reyes E, Hindebolt C, Langenwalter E, Polishing was accomplished with both Miley D. Abfractions and attachment loss pink and green Venus® Supra polishing in teeth with premature contacts in centric cups (Heraeus). A thin layer of Palaseal® relation:clinical observations. J Periodontol. (Heraeus) was placed and light-cured 2009;80(12):1955-1962. for 20 seconds to serve as a final “clear 7. Bartlett DW, Shah P. A critical review of coat” sealant (Figure 12). Finally, the non-carious (wear) lesions and the role of occlusion was evaluated with articu- abfraction, erosion and abrasion. J Dent Res. lating paper and any excessive occlusal 2006;85(4):306-312. contact was reduced, paying attention 8. van Dijken JW. Clinical evaluation of three to occlusal prematurities. An occlusal adhesive systems in class V non-carious le- guard was fabricated for the patient to sions, Dent Mater. 2000;16(4):285-291. wear at night. 9. Francisconi LF, Graeff SM , Martins Lde M, et al. The effects of occlusal loading on the mar- Conclusion gins of cervical restorations. J Am Dent Assoc. In the last 16 years, this author has 2009;140(10):1275-1282. treated thousands of abfraction lesions 10. Litonjua LA, Andreana S, Bush PJ, et al. with flowable composite with minimal Noncarious cervical lesions and abfractions: a failure. The restorations have been ob- re-evaluation. J Am Dent Assoc. 2003;134(7): served and followed up during subse- 845-850. quent dental hygiene visits. These flow- 11. Lowe R. The search for a low-shrinkage direct able composite restorations have not composite. Inside Dentistry. 2010;6(1):56-58. only resisted displacement but also have 12. Braga RR, Hilton TJ, Ferracane JL. Con­ shown no sign of toothpaste abrasion. traction stress of flowable composite materials This success is attributed to the selec- and their efficacy as stress-relieving layers. J tion of composite material and careful Am Dent Assoc. 2003;134(6):721-728. operative technique, which included mi- 13. Braem M, Lambrechts P, Vanherle G. cro-etching and thorough light-curing. Stress-induced cervical lesions. J Prosthet Currently, Venus Diamond Flow is an Dent. 1992;67(5):718-722. exceptional material for this application 14. Terry DA. Dimensions of color: creating in the author’s opinion because of its low high-diffusion layers with composite resin. shrinkage stress, thixotropic nature, Compend Contin Educ Dent. 2003;24(2 Suppl): lower modulus of elasticity, and excel- 3-13. lent polishability. This author believes 15. Feilzer AJ, De Gee AJ, Davidson CL. Setting that the bulk filling of an abfraction le- stress in composite resin in relation to configu- sion with new “low shrinkage stress” ration of the restoration. J Dent Res. 1987;66 flowable composite may become routine (11):1636-1639.

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