There may be a number of reasons why patients present requesting diastema closure, including aesthetic and periodontal factors.1 With aesthetically compromised smiles, patients may become self-conscious, experience low self-esteem, and/or cover their mouths with their hands while speaking.2 Also, when diastemas result from significant tissue loss, which can change the airflow between the teeth, the reason for requesting diastema closure may be to correct obvious phonetic problems, particularly with s and th sounds.3
There are many techniques and materials that can be employed to close diastemas. In some instances, the gingiva can be surgically repositioned,4,5 while in other instances, removable artificial gingiva masks the diastema, and pink-shaded porcelains can be used to correct the appearance of tissue loss.6,7
Approaches may vary from the use of reversible, noninvasive techniques such as composite bonding, to irreversible, invasive treatments such as ceramic veneers or crowns.2 In other instances, combination therapies involving veneers and orthodontic procedures may be indicated.8 Regardless, because diastemas may be caused by a variety of factors, careful analysis of clinical symptoms is mandatory for effective treatment, and prosthetic solutions that require sacrifice of sound tissue may be unnecessary.8 Therefore, care should be taken to prevent overtreatment.8
When placing indirect restorations to close diastemas, several problems could potentially result. For example, the affected teeth could appear too long, or attempts to eliminate black triangles between teeth could create an abnormal emergence profile.2 Furthermore, a smile with a high lip line and large spaces between the teeth requires careful attention to details of interproximal emergence profiles, biologic width, and papillary height in order to achieve exceptional aesthetic results.9 Specifically, if teeth are worn or the spaces are wide, the teeth will appear short and wide following diastema closure.9 Additionally, when spaces between the teeth are not symmetrical, achieving the correct gingival architecture may be impossible.9
Cases involving complex diastema closure in the anterior region further require clinicians to follow the principles of proportion, which are particularly important for achieving aesthetic results. Determining proper proportions dictates the amount of distal proximal reduction; whether to completely veneer the teeth or add to the interproximal zone; the number of teeth to be treated; and the position of prominences and concavities.10
When indirect techniques are used, they generally require multiple visits to enable proper placement of the laminates, crowns, or bridgework, and such procedures may also involve significant financial expense.1 While direct techniques can be economical and successful, they do present challenges in achieving satisfactory proximal contacts and contours.1 However, direct bonding in diastema closure cases enables clinicians to maintain complete control in the creation of a smile while simultaneously facilitating the restoration of form and function.10,11
CASE PRESENTATION
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| Figure 1. Preoperative facial view of the patients dentition. |
A 27-year-old female presented with the complaint that she did not like the spaces between her teeth. Facially, the diastemas were not as apparent, but she was very aware of the spaces and wanted the problem corrected (Figure 1). She felt the appearance of her smile would improve if the diastemas were closed.
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| Figure 2. View of the diastemas between tooth Nos. 5 and 6, and 6 and 7. | Figure 3. View of the diastema between tooth Nos. 10 and 11. |
A clinical evaluation was completed and 35-mm photographs were taken. Diastemas between tooth Nos. 5 and 6, 6 and 7, and 10 and 11 were noted (Figures 2 and 3). She demonstrated no pathology and had good occlusal function. The patient was not dissatisfied with the color or the overall shape and contour of her dentition.
TREATMENT PLAN
During the consultation, treatment options were reviewed and the decision was made to correct the diastemas using a direct composite system (4 Seasons Direct Esthetic Composite System, Ivoclar Vivadent). A conservative approach was warranted, given the health of the surrounding dentition and the patients overall satisfaction with the existing color and shape of her teeth. Therefore, the factors to be considered in this case included the following: ensuring that the restorations would match the surrounding dentition; achieving width-to-length ratios that would be acceptable to the patient; and achieving proper occlusal function. At the time of presentation, the width-to-length ratio was 65% to 70%; the ideal would be 80%.
The patient would benefit from a direct veneering technique for several reasons. Specifically, there would be only one appointment necessary to complete the restorations, there would be no temporization, and the result not only would be noninvasive but also reversible. The direct veneering technique would allow the dentist to utilize artistic skills to create additional tooth structure with the same qualities as the natural dentition.
The composite system of choice (4 Seasons) was selected based on the number and accuracy of shades available. The materials true color confidence resulted from 4 years of clinical research and testing that produced a true match to standard A-D shades in addition to mimicking the transparency, opacity, fluorescence, and value of natural tooth structure. With 40 composite shades and shade effects available, it would be possible in this case to match even the most aesthetically challenging aspects of this patients dentition.
CLINICAL PROTOCOL
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| Figure 4. The anticipated restorations were mocked-up on the patients teeth to verify shade selection and determine appropriate length. |
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| Figure 5. View of the putty matrix in the patients mouth. |
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| Figure 6. View of the completed putty matrix. |
A shade guide (4 Seasons shade guide) was used to determine which shade(s) of composite to place. The advantage of using this shade guide is that the shade tabs are made with ceramic to ensure long-term color stability and enable a consistent shade match. Once the shades were determined, the selected composite shades were placed on the unetched tooth surfaces of the mesial aspect of tooth No. 5, the mesial and distal aspects of tooth Nos. 6 and 10, and the distal aspect of tooth No. 7, then light-cured to simulate the permanent restorations (Figure 4). This mock-up verified accurate shade selection and provided a basis for the creation of a putty matrix (Virtual Putty, Ivoclar Vivadent), which would serve as a guide for proper lingual contouring and assist in determining the appropriate length of the permanent restorations (Figures 5 and 6).
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| Figure 7. The teeth were acid-etched for 30 seconds with 37% phosphoric acid. | Figure 8. A single component bonding agent was applied to the teeth. |
Once the putty matrix was complete, the interim composite material was removed with an explorer or curette and the teeth were then cleansed with pumice and isolated with cotton rolls. The teeth were acid- etched with 37% phosphoric acid for 30 seconds (Figure 7), rinsed thoroughly, and dried. A light-cured, single-component bonding agent (Excite, Ivoclar Vivadent) was applied to the etched surfaces and light-cured for 10 to 20 seconds (Figure 8). Once a homogeneous gloss was apparent on all prepared areas, the surfaces were then ready for placement of the permanent restorations.
The restorations were placed according to an anatomical technique that involved the use of a highly chromatic dentin shade composite overlaid with a colorless enamel value composite. In addition to a full complement of enamel and dentin shades that correspond to the A-D shade range, the selected composite system also features 3 unique value shades (high, medium, and low) that mimic natural enamel in the manner in which it diffuses the underlying dentin color to create a natural-looking depth and appearance.
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| Figure 9. A coating of A2 dentin composite was placed and contoured with a composite instrument. |
The lateral incisors were evaluated, and a dentin shade of A2 was selected. A thin coating of A2 dentin composite was placed on distal aspects of the lateral teeth, contoured with a brush and composite instrument (Figure 9), then light-cured for 10 seconds with a turbo tip on an Astralis 10 (Ivoclar Vivadent). The dentin shade was then overlaid with a medium-value shaded enamel composite, which was also light-cured for 20 seconds with a turbo tip on an Astralis 10 since this was the final cure. An A3 dentin composite was then similarly placed on the mesial aspects of the canines and cured, after which it was overlaid with a medium-value shaded enamel composite and light-cured.
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| Figure 10. Medium, fine, and super fine discs were used to shape and contour the restorations. | Figure 11. Final contours were created using a finishing bur. |
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| Figure 12. Astropol points were used to achieve a nice polished surface on the restorations. | Figure 13. View of the final restorations on tooth Nos. 5 through 7. |
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| Figure 14. View of the final restorations on tooth Nos. 10 and 11. | Figure 15. Facial view showing the completed restorations 5 days postoperatively. |
The restorations were shaped and contoured using medium, fine, and superfine discs (Sof-Lex XT, 3M ESPE, Figure 10), and the final contours were made with a finishing bur (TDF9 Finishing Bur, Axis, Figure 11). To achieve a nice, polished surface, a PoGo Wheel (DENTSPLY Caulk) and Astropol points (Ivoclar Vivadent) were used (Figure 12). The final restorations were photographed at completion (Figures 13 and 14) and again 5 days postoperatively (Figure 15).
CONCLUSION
Many anterior aesthetic cases present themselves during the course of daily practice routine. Selecting the proper treatment involves (1) the usual challenges of addressing the needs and expectations of the patient, (2) determining what degree of change is necessary to achieve the desired result, and (3) anticipating whether or not the patient will accept the treatment plan. Many aesthetic cases fall into the direct veneering category. The beauty of the direct veneering technique is that it provides the dentist with the freedom to be creative using a simple restorative technique and affords the patient a treatment that is completed in 1 day with beautiful, aesthetic results.
The concepts surrounding the diastema closure presented in this article are not overly complicated. Key to realizing a beautiful restoration for this purpose is the use of composites with superior handling, consistency, and color accuracy, and a restorative method that is very simple. Instead of trying to find an enamel shade, dentin shade, and incisal shade as in a conventional shaded layering technique using an anatomical approach enables the selection of a value of enamel and the matching of the underlying dentin layer, allowing the color to radiate from within the restoration just as it occurs in a natural tooth.
References
1. Lacy AM. Application of composite resin for single-appointment anterior and posterior diastema closure. Pract Periodontics Aesthet Dent. 1998;
10(3):279-286.
2. Helvey GA. Closing diastemas and creating artificial gingiva with polymer ceramics. Compend Contin Educ Dent. 2002;23(11):983-996.
3. Tallents RH. Artificial gingival replacements. Oral Health. 1983;73(2):37-40.
4. Han TJ, Takei HH. Progress in gingival papilla reconstruction. Periodontol 2000. 1996;11:65-68.
5. Azzi R, Etienne D, Carranza F. Surgical reconstruction of the interdental papilla. Int J Periodontics Restorative Dent. 1998;18(5):466-473.
6. Gardner FM, Stankewitz CG. Using removable gingival facades with fixed partial dentures. J Prosthet Dent. 1982;47(3):262-264.
7. Passon C. Enhanced prosthetics using the gingival mask. Oper Dent. 1992;17(3):101-105.
8. Fuhrer N, Vardimon AD. Clinical analysis and treatment of spaced dentition. Pract Periodontics Aesthet Dent. 1997;9(5):493-501.
9. Jones LA, Robinson MY. Case study: esthetic and biologic management of diastema closures using porcelain-bonded restorations for excellent and predictable results. J Cosmet Dent. 2002;18(3):73-84.
10. Blitz N. Direct bonding in diastema closure high drama, immediate resolution. Oral Health. 1996;86(7):23-26.
11. Terry DA, McLaren EA. The interproximal zone: a class III restoration. Contemp Esthetics Restor Practice. 2001;5(11):46-56.
Dr. Lowe is the clinical director of the Pacific Aesthetic Continuum (PAC~live), University of the Pacific, San Francisco. He maintains a full time functional aesthetic private practice in Vancouver, British Columbia. Dr. Lowe can be reached at (604) 683-2483 or edlowe@axionet.com.
