Table of Contents

Implants

Inside Dentistry

March 2008, Volume 4, Issue 3
Published by AEGIS Communications

Elective Veneers: Meeting Patient’s Expectations While Addressing Current Ethical Questions of Elective Care

Gary M. Radz, DDS

The public demand for elective dentistry has never been higher. Media attention, television shows, the Internet, and over-the-counter products have all combined to make the general public aware that there are very achievable ways for the dentist to be able to improve the appearance of smiles.

The public is growing aware of the potential benefits of esthetic dental products, with bleaching products and veneers leading the way. Many dentists, in an effort to meet the public demand, have now made these treatment options available to their patients. This has created many patients who are now dramatically happier with the appearance of their smiles and many dentists are now experiencing the emotional and professional rewards associated with enhancing smiles.

This boom in popularity in elective dentistry has not come without a cost. As with any elective procedure in dentistry or medicine, there are risks associated with the procedure. Elective dentistry, as with plastic surgery, has seen the occasional dramatic failure show up on the Internet or on television. This was to be expected, but that does not mean that dentists should accept failure.

First and foremost, we as a profession need to be better and more consistent with informed consent issues. Although an important part of any dental procedure, nowhere is this more important than with elective dentistry. Recently, Inside Dentistry published an article addressing the parameters of informed consent.1 Informed consent is a critical component before any elective treatment can be considered.

Recently, in the area of veneers there has been a significant amount of published opinion and editorial by some of the profession’s icons expressing concern about the over-treatment of patients, especially as it pertains to veneers. Much of this concern is established from a scientific standpoint and well thought out from an ethical point of view. The purpose of this article is three-fold:

• to summarize some of the concerns expressed by several of the most respected cosmetic/restorative dentists in the profession;

• to offer examples of conservative veneer therapy that would comply to the standards that these leaders in our field would hopefully agree is acceptable and ethical elective treatment; and

• within these examples demonstrate conservative veneering techniques that have been proven to have the ability to provide an acceptable esthetic result while providing that result with minimally invasive techniques that have the potential for long-term clinical success.

Recent Opinions From Our Profession&Rsquo;s Leaders

In the past 3 to 4 years there have been a number of articles and editorials expressing concern regarding overtreatment and overtreatment planning with porcelain veneers. Heymann and Swift’s recent editorial expresses concern regarding “the wanton disregard for the sanctity of tooth structure in the expressed, but misguided pursuit of ‘optimal’ esthetics and function,” and “teeth that never even required veneering to begin with are ravaged into dentin in pursuit of optimal esthetics and a potential appearance on a tabloid cover.”2 They end this editorial with the question: “Is tooth structure not sacred anymore?” In a more recent editorial Heymann more clearly refines his concern, which other dentists share, in stating, “A growing number of case reports reveal veneers so deeply prepared into dentin that the results inevitably lead to premature replacement of the failed restoration with crowns, endodontic treatment, or even implants.”3

A key point of concern is not necessarily the use of veneers for esthetic enhancement, but rather the use of an aggressive preparation style created by the requirements of the ceramic material and/or the lack of knowledge of the practitioner about material choice and/or proper preparation design. In 1991, Christensen discussed the different types of veneer preparation design and expressed concern over a “deep tooth preparation.”4 His concerns were regarding the overpreparation of the tooth as well as the ability to successfully bond to an all-dentin preparation design on a long-term basis. Fifteen years later, Christensen again expressed the same concern with aggressive preparation designs for veneers.5 More recently, Barghi and Overton stated: “It is a disservice to the patient to perform these procedures [deeply prepared veneers] before clinical evidence has demonstrated success with veneers bonded to dentin as it has with veneers bonded to enamel.”6

The concerns expressed by these established leaders are based on research and are evidence-based. A short review of a sampling of research clearly demonstrates that veneer preparations that are mostly enamel can be highly successful. In 1998, Friedman, one of the pioneers and a current leader in porcelain veneers, published a 15-year study that demonstrated a 93% success rate with porcelain veneers that were prepared in enamel;7 in 2000, Dumfahrt showed a 91% success rate in veneers prepared in enamel;8 and Peumans et al demonstrated a 100% retention success rate in a 5-year study of porcelain veneers bonded to enamel.9 There are numerous other studies to demonstrate the clear superiority of a bond of porcelain to enamel as opposed to dentin.10-12

The concerns expressed by these industry leaders are directed toward a disturbing trend to prepare a perfectly healthy tooth into the dentin to create the proper preparation for a pressed-ceramic restoration. Generically, the preparation guidelines for the proper reduction for a pressed-ceramic veneer require a minimum of 0.8 mm of reduction. However, the average facial enamel thickness of a maxillary central incisor is 0.6 mm. The problem is now evident; it is virtually impossible for a maxillary anterior tooth to be properly prepared for a pressed-ceramic restoration and have much, if any, enamel with which to bond. This is the one of the primary issues that has led respected leaders such as Christenson, Heymann, Friedman, Barghi, Goldstein, Swift, and many others to express concern over what they are seeing. These doctors have been the ones who have been placing and teaching veneer concepts for over 20 years. They are not opposed to porcelain veneers as a treatment modality. Generally, they have two concerns: first, the over-diagnosis of porcelain veneers when other, more conservative treatment modalities will provide an acceptable esthetic change;5 and second, the overpreparation of tooth structure when veneers are indicated and a lack of understanding of the materials and techniques for creating a conservative veneer that can be bonded to enamel.

The first concern deals with technical, diagnostic, and ethical issues beyond the scope of this article. However, Jackson addressed some of these issues in a recent editorial13 eloquently discussing points of concern that we all, as professionals, need to take into consideration before passing judgment on others. It is the second concern that this article will address.

Following are case studies demonstrating the material and preparation options currently available that provide the dentist with the ability to create positive esthetic change in a manner that allows for a technique in which most if not all of the veneer restoration is bonded to enamel.

Conservative Material Selection for Porcelain Veneers

Porcelain veneers can be divided into two different fabrication methods: stacked porcelain or pressed ceramic.

Pressed ceramic, (IPS Empress, Ivoclar Vivadent, Amherst, NY; OPC 3G, Pentron Clinical Technologies, LLC, Wallingford, CT, and others) by the nature of their fabrication, require 0.8 mm of reduction.12 As noted earlier, this requirement will in many instances remove most of the enamel from an anterior tooth, thereby minimizing or eliminating the ability to bond to enamel. Pressed-ceramic veneers still do have a place in certain clinical situations. Most notably, if the tooth to be veneered is structurally weakened with a large existing restoration (a large Class IV composite for example) the additional strength of a pressed ceramic may make this material a better choice. Another situation would be a smile makeover that included the placement or replacement of an anterior crown. Again the additional strength of a pressed ceramic could influence the dentist to choose pressed ceramic in this situation. Lastly, it should be mentioned that manufacturers of pressed ceramic systems have been and currently are working on materials and techniques that will allow for the fabrication of a thinner pressed-ceramic veneer.

Stacked porcelain is created by using either a foil technique or refractory die where porcelain powder is mixed with a liquid and hand-stacked.14 Using this technique, it is possible to routinely fabricate a veneer that is 0.3 mm to 0.5 mm thick.15 A veneer this thin allows for a preparation design that has the potential to be all or mostly in enamel, thereby minimizing the loss of tooth structure and at the same time allowing for the ability to bond to enamel. When discussing the types of veneers used in a no-preparation design, these veneers are always created from a stacked-porcelain technique.

Once the differences between the two materials are discussed, it begins to become obvious that the more conservative nature of the inherently thinner stacked-porcelain veneer is a better choice when providing elective dentistry in many cases.

Stacked Porcelain Veneer Preparation Options

The “Standard” Preparation Design: Case Study
A young woman presented to the office with cosmetic concerns (Figure 1). Conservative methods of bleaching, microabrasion, and bonding had been attempted with unacceptable results. The patient was told about the risks and benefits of porcelain-veneer therapy and selected to proceed with this treatment.

Conventional teaching in stacked-porcelain veneers has recommended the reduction of 0.5 mm of tooth structure.16 Figure 2 demonstrates the use of a 0.5-mm depth-cutting diamond (Axis Dental Corp, Irving, TX) to uniformly create 0.5 mm of facial reduction. Next, a medium-grit chamfer diamond was used to uniformly reduce the facial tooth structure by 0.5 mm, and achieve an incisal reduction of 1 mm. Figure 3 shows the final preparations before the final impressions.

The ceramist was instructed to fabricate minimal-thickness, stacked-porcelain veneers (SoftSpar, Pentron Clinical Technologies, LLC). Provisional restorations not only improved the patient’s esthetics, but they also provided a preview of the final restoration (Figure 4). Figure 5 shows the final veneers.

A 3-year postoperative photograph demonstrates an excellent esthetic response with good soft tissue health (Figure 6).

Magne and Belser recently published a technique that engages a paradigm shift in thinking in regard to preparation guidelines.17 This technique has been used and modified by others,18 but the concept creates the potential for an even more conservative preparation model.

The premise of their technique is the need to create room for 0.5 mm of porcelain and not necessarily remove 0.5 mm of tooth structure. In this technique an anatomically correct wax-up is created on the preoperative model. A silicone putty matrix of the wax-up is fabricated, thereby capturing the detail of the wax-up. The putty matrix is then loaded with temporary material and placed onto the unprepared teeth. Upon removal, the wax-up has effectively been transferred into the patient’s mouth. Now the clinician needs to remove 0.5 mm for the facial aspect of this transferred wax-up. This technique has the ability to minimize the amount of tooth structure removed and yet still provide the ceramist with adequate room to fabricate the final restoration. Although not applicable to all cases, the idea certainly has merit and has seen growing popularity within cosmetic dentistry.

A Conservative Modification of the “Standard” Stacked-Porcelain Veneer Preparation: Case Study
A 28-year-old man wanted to improve the appearance of his smile before his wedding (Figure 7). The patient was educated on the options of bleaching, direct bonding, and porcelain veneers, which included reviewing the risks, benefits, and expected esthetic outcomes of these treatment modalities. Given this information, the patient chose to have porcelain veneers placed on teeth Nos. 7 through 10.

Because the author wanted to create only minor changes to create better symmetry, contour, and close some minimal spaces, the preparations were designed to be as minimally invasive as possible. The facial aspect of the enamel was roughened with an chamfer diamond (Axis Dental Corp); using the same diamond, a visible margin was created mesially, distally, and gingivally (Figure 8). These preparations were so minimal that local anesthetic was not used. Additionally, no temporaries were fabricated as the patient did not need them for esthetic or sensitivity issues.

The final restorations were highly translucent stacked-porcelain veneers (Avante®, Pentron Clinical Technologies, LLC) that demonstrated an average thickness of 0.3 mm. Figure 9 shows a 6-month postoperative view of the four veneers.

No-Preparation Veneers Using Stacked Porcelain Veneers: Case Study
In recent years the concept of “no-preparation” porcelain veneers has seen growing popularity among the general public and dentists. The idea of being able to provide patients with the esthetic results they are looking to achieve without reduction of tooth structure is highly appealing to all.

However, this idea has been met with mixed results and opinion throughout the profession. Knowledgeable and experienced cosmetic dentists and ceramists have questioned the ability to place a thickness of porcelain on a tooth without negatively affecting the soft tissue health and/or to create a restoration that is not grossly overcontoured.

Figure 10 demonstrates this concern. This 13-year-old patient presented 6 weeks after having 8 veneers fabricated from a popular no-preparation porcelain by a local dentist. Only 5 H of the original veneers remained, the porcelain was dramatically overcontoured, and periodontal probing of the areas created significant bleeding around all of the veneers. Hopefully, this is not representative of all no-preparation porcelain veneers. But it does serve as an extreme example of what has dentists concerned about this concept.

It is possible to create no-preparation veneers and have an excellent esthetic result. However, it is technically demanding for both the dentist and the ceramist.

Dr. Dennis Wells and ceramist Mark Willes have developed a technique to create a no-preparation veneer system (Durathin®, Experience Dental Studios, Provo, UT) using a stacked-feldspathic porcelain (Avante). This system starts with learning to diagnose cases that can be success-fully treated with a no-preparation concept. Dr. Wells’ system is dependent on proper diagnosis.19

A 30-year-old patient presented with esthetic concerns (Figure 11). She verbalized a strong preference to not have any of her natural tooth structure removed. When educated on the potential of no-preparation veneers she requested to pursue this treatment option.

Dr. Wells’s technique requires the fabrication of prototypes in direct composite (EvoCeram®, Ivoclar Vivadent). Teeth Nos. 7 through 10 were mocked-up in the mouth with the composite resin (Figure 12). With the patient’s approval of the prototype, an impression of the prototypes and a preoperative impression were sent to the laboratory for fabrication of the stacked-porcelain veneers.

The final restorations demonstrate that an experienced and talented dentist and ceramist can create a highly esthetic result in a no-preparation design. Figure 13 shows not only beautiful porcelain work, but excellent soft tissue response

Dr. Wells and Mr. Willes have demonstrated that it is certainly possible to create a highly esthetic result using the no-preparation concept. However, it requires meticulous attention to detail and a great deal of experience. A no-preparation veneer may be the most demanding of veneer designs. However, the benefits of no destruction of natural tooth structure make this technique a highly desirable treatment option.

Conclusion

The limited scope of this article has been to address and raise awareness of when, where, and how stacked-porcelain veneers can be used conservatively and effectively to help patients achieve the esthetic result they are looking to achieve. In each of these examples there could be other more conservative and more aggressive ways to achieve an esthetic result. What was addressed here were some of the legitimate concerns that have been raised and a presentation of some of the ways that we, as dentists, can achieve an esthetic result in a conservative manner.

Pressed ceramics are a wonderful addition to our esthetic dental “toolbox” and in many cases is a great restoration for a given clinical situation, including veneers. This article did not address a severely discolored dentition, teeth with extensive existing restorations, endodontically treated teeth, or difficult/challenging occlusal schemes that could all lend themselves to being excellent candidates for pressed ceramics.

The purpose of this article was to address a current concern and to summarize the author’s understanding of the opinions of some the industry’s leaders and to present materials and techniques in veneer therapy that can positively address the published concerns of these leaders.

There are many different ways for dentists to help patients achieve a better smile. It is the dentist’s responsibility to develop a full understanding of all of the material and technique options available so that they present the patient with the treatment options available so that the patient can make an informed decision on how he or she would like to proceed.

Lastly, it is important that dentists do understand the complex ethical issues involved with elective dentistry. This article has listed a number of references where these ethical issues have been discussed. Dentists providing elective dentistry should be reading these opinions and others to appreciate the moral, ethical, and legal complexities involved with cosmetic dentistry.

Dr. Jackson stated “judge ethics, ethically.”13 His point is an important one; let us not pass judgment on other professionals without all the facts. Let us treat our fellow dentists professionally and our patients ethically.

Acknowledgments

Dr. Radz would like to recognize the artistic talents of his ceramist William “CK” Kim, demonstrated in Cases 1 and 2. He would also like to express his gratitude to Dr. Dennis Wells for sharing his photography of the final case presented (ceramics by Mark Willes, Experience Dental Studios).

References

1. DiMatteo AM. Dissecting the debate over the ethics of esthetic dentistry. Inside Dentistry. 2007;3(8):56-58.

2. Heymann HO, Swift EJ Jr. Is tooth structure not sacred anymore? J Esthet Restor Dent. 2001;13(5):283.

3. Heymann HO. Right on Ron! J Esthet Restor Dent. 2007;19(1): 1-2.

4. Christensen GJ. Have porcelain veneers arrived? J Am Dent Assoc. 1991;122(1):81.

5. Christensen GJ. Veneer mania. J Am Dent Assoc. 2006: 137(8)1161-1163.

6. Barghi N, Overton JD. Preserving principles of successful porcelain veneers. Contemporary Esthetics. 2007;11(1):47-51.

7. Friedman MJ. A 15-year review of porcelain veneer failure—a clinician’s observation. Compend Cont Educ Dent. 1998;19(6): 625-638.

8. Dumfahrt H, Schaffer H. Porcelain laminate veneers: a retrospective evaluation after 1 to 10 years of service. Int J Prosthodont. 2000;13(1): 9-18.

9. Peumans M, Van Meerbeek B, Lambrechts P, Vuylsteke-Wauters M. Five-year clinical performance of porcelain veneers. Quintessence Int. 1998;29(4): 211-221.

10. Meiers JC, Young D. Two year composite/dentin durability. Am J Dent. 2001;14:141-144.

11. Hashimoto M, Ohno H, Kaga M, et al. Resin-tooth adhesive interfaces after long-term function. Am J Dent. 2001;14(4): 211-215.

12. Nash RW. What’s different about IPS Empress esthetic. Contemporary Esthetics and Restorative Practice. 2005:52-57.

13. Jackson RD. Judging ethics ethically. J Esthet Restor Dent. 2007;19(4): 181-182

14. Puri S. Techniques used to fabricate all-ceramic restorations in the dental practice. Compend Cont Educ Dent. 2005;26(7): 519-525.

15. Nash RW. Why conservative preparations for elective laminate veneers? Contemporary Esthetics and Restorative Practice. 2002:70-76.

16. Rosenthal L. The state of the art in porcelain laminate veneer, part I: simple cases. Esthetic Dentistry Update. 1991;2(5):90-93.

17. Magne P, Belser UC. Novel porcelain laminate preparation approach driven by a diagnostic mock-up. J Esthet Restor Dent. 2004;16(1): 7-18.

18. Radz GM. A preparation technique to minimize tooth reduction in porcelain veneers. Oral Health. 2006:15-19.

19. Durathin Live. Presented by Dr. Dennis Wells and Mark Willes, Brentwood, Tennessee; July 26-28, 2007.

About the Author

Gary M. Radz, DDS
Associate Clinical Professor
University of Colorado School of Dentistry
Denver, Colorado

Private Practice
Cosmetic Dentistry of Colorado
Denver, Colorado