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THE ROLE OF COSMETIC DENTISTRY IN RESTORING A YOUTHFUL APPEARANCE
Cover Story
THE ROLE OF COSMETIC DENTISTRY IN RESTORING A YOUTHFUL APPEARANCE JEFF MORLEY, D.D.S.
he advent of new materials and technologies in dentistry during the last 30 years has brought with it the promise of a new era in restorative dentistry for the 21st century. Coupled with the profession’s aggressive pursuit of prevention and patient education is the fact that patients are keeping an ever-increasing number of teeth into advanced age.1-4 Modern restorative techniques have combined with earlier and better treatment of periodontal disease to achieve such results, and the impact of fluoridation as a caries-preventive modality also has aided in prolonging the life span of countless dentitions. The traditionally accepted role of dentist as manager of a predictable and protracted decline from repair of decay to full-coverage protection to partial or complete tooth loss has increasingly come under attack. Today, the concept of keeping most or all of one’s
A
S
T
R
A
C
T
Background. Dentistry is faced with a population that is getting older and keeping more of its natural teeth. Smiles show physical and esthetic signs of aging. Advances in the area of cosmetic dentistry now offer the dental profession new opportunities in conservative and esthetic restorative procedures that have the potential to reverse the signs of dental aging, thereby making patients appear younger. Case Description. The physical and esthetic attributes of an aged dentition are identifiable. Tooth wear over time alters the appearance of the teeth and smile in a way that is perceptible to dentists and laypeople. Bonding and adhesive ceramic restorative procedures have the potential of reversing the esthetic manifestations of the aging process for teeth. Specific diagnostic tools, including a composite resin mock-up and construction of an incisal putty matrix, allow for previsualization of possible treatment outcomes and allow clinicians to resolve occlusal as well as esthetic treatment concerns before initiating actual treatment. Clinical Implications. The ability to make patients look younger through cosmetic enhancement of teeth and smiles has tremendous implications for the future practice of dentistry. Dentists who have the training and skills to meet the increasing demand for esthetic procedures by patients seeking to restore a youthful appearance may find an expanded role within their practices for this type of treatment.
teeth for an entire lifetime has become an attainable goal. 1166
B
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
COVER STORY From a purely cosmetic standpoint, the value of the appearance of one’s teeth has taken on a greater importance in Western society. Right or wrong, the public places an increasing priority on a healthy and attractive smile. The dental profession’s traditional domain, centered around the eradication of disease, now finds itself on the threshold of uncharted territory: the enhancement of appearance. Yet, foundations of health, proper function and sound scientific principles also must prevail. As we enter the 21st century, the care of a rapidly aging population indeed may be the greatest challenge the profession will face in the years ahead.5 CHANGING DEMOGRAPHICS
The American population is getting older. A recent demographic survey indicates that more than 50,000 Americans per day are reaching the age of 50 years, and that this trend is expected to continue throughout the entire first decade of the new century.6 Additionally, the average life expectancy of Americans has been increasing at an accelerated rate. While the average life expectancy of all Americans (male and female, all races) was 35.5 years in 1798, by 1900 it had increased to 49.2 years, by 1970 to 70.1 years and by 1999 to 76 years.7 In fact, some demographers have predicted that American children born in the waning years of the 20th century my well have a life expectancy that approaches or even exceeds 100 years.7 Between 1990 and 2020, the segment of the U.S. population aged 65 to 74 years is expected to grow 74 percent.7
Figure 1. Natural dentition of a 58-year-old woman showing discoloration and visible signs of aging.
Early findings regarding this new demographic phenomenon have been predictable. Teeth that arguably may have only
The newer techniques are more esthetically pleasing and lend themselves to making cosmetic enhancements at the very same time that they restore. been designed to last 30 years in our ancestral lineage are now being called upon to last 50, 60, 70 years and beyond. Research into this expanding field has been scanty at best. A review of the literature reveals a growing interest in the subject of the aging dentition. However, the majority of pub-
lished information has focused on restorative and therapeutic opportunities created by old teeth and periodontium or on basic dental care in a medically compromised population.8-11 Almost no studies have delved into the psychologic and emotional consequences of patients’ perception of aged smiles. Furthermore, there seems to be little understanding within dentistry as to the origins and nature of a movement toward “youth at all costs” that appears to be thrusting itself on the profession. DENTISTRY’S NEW RESTORATIVE TECHNOLOGY
While cosmetic dentistry certainly has been part of the profession for centuries—even further back into antiquity than the time of George Washington’s famous prostheses12— the advent of conservative tooth restoration through bonded ceramics and resin composites literally has changed a profession’s way of thinking that has lasted well over a cen-
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
1167
COVER STORY into the “age of augmentation.”14 PHYSICAL SIGNS OF AGING IN TEETH AND SMILES
Figure 2. Patient showing classic facial esthetics of aging. Progressive wear of dentition has led to loss of vertical dimension.
Figure 3. Cosmetic reconstruction reestablishes proper vertical dimension, lip support and reveal of maxillary anterior teeth associated with a youthful smile.
tury. While still considered “new,” the dental adhesive technology introduced in 1955 by Buonocore13 is rapidly approaching its 50th anniversary. Combined with an incredible explosion in the field of dental materials, bonding has allowed for conservative restorative treatment opportunities never before dreamed possible. Porcelain veneers, non–metal-based crowns, and the ability to seal and restore 1168
teeth or fragments of teeth using adhesive materials and techniques all have shown tremendous promise and increasing reliability. These newer techniques also are more esthetically pleasing and lend themselves to making cosmetic enhancements at the same time that they restore. In fact, it has been said that bonding, in all of its various forms, has moved dentistry out of the “age of amputation” and
The esthetic manifestations of anterior tooth aging fall into three basic categories (Figure 1): dwear and the effects of erosion, attrition, abrasion and abfraction; dsize and position of teeth in relation to each other and to surrounding tissues; dcolor. Of course, other factors are associated with tooth aging that also are worthy of discussion. Teeth transform histologically and even chemically over time.15 The supporting bone and surrounding soft-tissue structures of the face undergo a metamorphosis with aging (Figure 2). As vertical dimension and lip support are lost, oftentimes the resulting muscle tension can cause soft-tissue changes in facial features away from the mouth, including the area around the eyes.16 Restoration of the aged dentition cosmetically and functionally, providing adequate soft-tissue support and tooth “reveal” (the amount of tooth or teeth showing), has the potential to make patients look younger (Figure 3).17 Wear. Wear in one form or another ultimately alters the appearance of the anterior teeth in predictable patterns that not only are recognizable by dentists but are subliminally apparent to the lay public as well.18 The most dominant force affecting tooth esthetics is abrasion, the contact of one tooth against another in protrusive and lateral function. In a typical Class I occlusion, anterior guid-
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
COVER STORY ance and “cuspid rise” will result in millions of tooth-to-tooth contacts over a lifetime. Although emphasis within the profession has been focused on the effects of bruxism and clenching, it should be noted that the visual components of these conditions are only an acceleration of what might otherwise be happening much more slowly through the aging process. Size. When compared with a more youthful-looking dentition (Figure 4), an aging dentition demonstrates the effects of specific esthetic changes that have occurred over time. The youthful smile is distinguished by its long central incisors, which typ-
Figure 4. Natural dentition of a 23-year-old woman showing typical appearance of a youthful smile.
Teeth tend to drift toward the middle of the face over time, and crowding of the dentition worsens with age. Figure 5. The intercommissure line is used as a guideline to determine proper esthetics for a youthful smile.
ically are noticeably longer than the lateral incisors adjacent to them. This gives the central incisors a distinct rectangular shape, with a width-to-height ratio in the range of 75 to 80 percent. The younger dentition also shows well-defined incisal embrasures, particularly in the maxillary anterior teeth. Incisal contact points for these teeth quite often are located at the junction of the incisal and middle thirds. As the teeth
wear down over time, not only does their width-to-height ratio change (approaching or exceeding 100 percent), but also the edges of the teeth often wear into the incisal contacts and thus wipe out incisal embrasure definition.19 Position. Changes in tooth position associated with the aging process are not easily identified. The absence of longterm tracking studies, studies using only small sample sizes
and investigators’ inability to factor out variables all have resulted in inconclusive findings. At least one recent long-term study has shown that teeth tend to drift toward the middle of the face over time, and that crowding of the dentition worsens with age.20 The position and amount of reveal of the maxillary anterior teeth also play a role in the perception of age. A useful parameter uses the amount of tooth reveal below the intercom-
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
1169
COVER STORY thickness over time, the dentin color begins to dominate tooth shades, and the teeth become progressively darker. TECHNIQUES FOR RESTORING YOUTHFUL APPEARANCE
Figure 6. Thirty-year-old patient showing more than 80 percent of maxillary teeth under intercommissure line.
Figure 7. Altered image of patient in Figure 6, with maxillary anterior teeth repositioned apically, showing how reduction in tooth reveal and inadequate amount of maxillary teeth below the intercommissure line appear to age the patient.
missure line, an imaginary line connecting the corners of the lips in a full smile position (Figure 5).21 Youthful smiles generally reveal 75 to 100 percent of the maxillary teeth below the intercommissure line. As the amount of reveal dips below 40 percent and approaches or becomes zero, the face becomes markedly aged (Figures 6 and 7). Color. As teeth age, physiologic and environmental condi1170
tions play havoc with tooth color. Although there is no evidence in the dental literature that tooth color alone plays any role in dental health, darker teeth generally are associated with older age.22 As the dental pulp shrinks, darker secondary dentin is left behind. At the same time, pigments and ions are absorbed into the teeth as a result of normal day-to-day oral habits. Combined with an ever-decreasing enamel
Simply put, any restorative, orthodontic, periodontic or surgical form of dental treatment that in some fashion counteracts or mitigates any of the esthetic attributes of an aged dentition has the potential to reverse the appearance of aging. Tooth bleaching, for example, can have dramatic youth-enhancing effects on select patients whose only problem with their otherwise healthy dentitions is that their teeth are stained, dark or yellow. The restoration of appropriate and youthful tooth length and proportion also is a treatment modality with tremendous potential. Most commonly accomplished through the judicious use of porcelain or resin composite veneers (but sometimes through the use of full-coverage bonded ceramic crowns), the restoration of tooth length lost to the predations of time or parafunctional habits can seem to turn back the clock when performed as part of a carefully thought-out treatment plan. Because the anterior teeth also are involved in the occlusal schemes for any given dentition, careful consideration of the exact length and position of the anterior teeth in the esthetic zone becomes critical.23,24 Mounting study casts on an articulator before defining a cosmetic treatment plan will give the clinician an opportunity to analyze the occlusal patterns of any patient and will
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
COVER STORY provide valuable clues as to the limits of providing a cosmetic as well as functional result. The so-called “mock-up” of a planned cosmetic treatment also has been shown to be quite useful (Figure 8). Not only can the mock-up be used to communicate potential results to the patient, but also it allows the clinician to visualize the desired results and solve potential problems before providing treatment to the patient. While the models traditionally are constructed in wax, a new technique involves fabricating the mock-up in hybrid resin composite that has been cured on a stone model.25 A simple technique calls for coating the stone model with multiple coats of any dentin adhesive and light-curing it after allowing the solvents in the adhesive to evaporate. This technique provides an adequate foundation that promotes adherence of composite resin directly to the stone model. Mock-ups made in this fashion are substantially more durable than traditional waxups and allow for fabrication of stints, registrations and guides such as the incisal putty matrix. The incisal putty matrix is the clinician’s primary registration in determining and verifying the exact position of the incisal edges of the anterior teeth during the preparation and provisionalization phase of cosmetic restorative treatment.26
Figure 8. Both the composite mock-up and incisal putty matrix are useful tools in cosmetic dentistry.
coupled with the evidence that people are living longer, are beginning to paint a compelling picture of an aging population with an increasing number of natural teeth. What will be the dental care needs of this aging
Each practitioner also must ask whether dental treatment for the purpose of restoring the appearance of youth shoud be performed.
CONCLUSION
The dental profession has done a remarkable job during the last 50 years in eradicating dental caries and educating the public in the importance of good oral hygiene. Great strides have been made toward reducing the number of teeth lost to periodontal disease. These facts,
population? If the dental profession is actively sought out by the public for the purpose of restoring a youthful appearance, will the profession be prepared? Many questions remain
unanswered or unexplored. Current techniques in cosmetic dentistry have shown great efficacy and reliability when properly used by trained clinicians. Clinicians providing this type of treatment not only must be proficient in current cosmetic techniques and materials but also must have a firm grasp of occlusal principles and a sound foundation of knowledge of basic dentistry. These considerations notwithstanding, each practitioner also must ask whether dental treatment for the purpose of restoring the appearance of youth should be performed. Who will benefit from this treatment? Who will pay for it? Will certain select members of our society be able to avail themselves of this new expanded role for dentistry while other members in need are blocked from receiving such care (by cost, by access or by both)? And what may happen if the profession holds the power to reverse the signs of the aging process when it comes to the oral environment but then chooses not to use it? At least for the moment, the
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
1171
COVER STORY
Dr. Morley is an associate clinical professor, School of Dental Medicine, State University of New York, University at Buffalo. He also maintains a private
population that dentistry serves continues to benefit from the scientific and technological advances that have made dentistry such a remarkable profession. ■
1. Brown LJ, Swango PA. Trends in caries experience in U.S. cisco, Calif. 94123. employed adults from Address reprint 1971-74 to 1985: crossrequests to Dr. sectional comparisons. Morley. Adv Dent Res 1993;7(1):52-60. 2. Johnson BD, Mulligan K, Kiyak HA, Marder M. Aging or disease? Periodontal changes and treatment considerations in the older dental patient. Gerodontology 1989;8(4):109-18. 3. White BA, Caplon DJ, Weintraub JA. A quarter century of changes in oral health in the United States. J Dent Educ 1995;59(1):19-57. 4. Marcus SE, Drury TR, Brown LJ, Zion GR. Tooth retention and tooth loss in the permanent dentition of adults: United States, 1988-1991. J Dent Res 1996;75(special issue):684-95. practice at 1648
Union St., San Fran-
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5. Cunningham R. Perspectives: solution gap looms for financing baby boomers’ future long-term care needs. Med Health 1998 Mar 23;52(12)(suppl):1-4. 6. Vatter RH. Boomers enter the golden fifties. Stat Bull Metrop Insur Co. 1998;79(1):2-9. 7. Friend T, DeBarros A. Science finds no limit on life span. USA Today. March 17, 1999;Special report:5D-7D. 8. Ettinger RL. Restoring the aging dentition: repair or replacement? Int Dent J 1990; 40:275-82. 9. Iacopino AM, Wathen WF. Geriatric prosthodontics: an overview. Part 1: pretreatment considerations. Quintessence Int 1993;24:259-66. 10. Dolan TA, Mulligan R, Berkey D, Saunders MJ. Enhancing the oral health of older adults: recommendations for action. Spec Care Dentist 1996;16(6):229-36. 11. MacEntee MI. Clinical epidemiologic concerns and the geriatric prosthodontic patient. J Prosthet Dent 1994;72:487-91. 12. Fastlicht S. Tooth mutilations and dentistry in pre-Columbian Mexico. Chicago: Quintessence; 1976. 13. Buonocore MA. A simple method of increasing the adhesion of acrylic materials to enamel surfaces (abstract). J Dent Res 1955;34:749. 14. Golub-Evans J. Unity and variety: essential ingredients of a smile design. Curr Opin Cosmet Dent 1994;2:1-5. 15. Dzierzak J. Restoring the aging dentition. Curr Opin Cosmet Dent 1994;2:24-32. 16. Koury ME, Epker BN. The aged face, the facial manifestations of aging. Int J Adult Orthodon Orthognath Surg 1991;6:81-95.
17. Frush JP, Fisher RD. The age factor in dentogenics. J Prosthet Dent 1957;7:5-13. 18. Donachie MA, Walls WG. Assessment of tooth wear in an aging population. J Dent 1994;23:157-64. 19. Morley J. Smile design—specific considerations. J Calif Dent Assoc 1997;25(9):633-7. 20. Richardson ME. A preliminary report on lower arch crowding in the mature adult. Eur J Orthod 1995;17:251-7. 21. Goodkind RJ, Schwabacher WB. Use of a fiber-optic colorimeter for in vivo color measurements of 2,830 anterior teeth. J Prosthet Dent 1987;58:535-42. 22. Morley J. Advanced smile design. Presented at: Postgraduate Advanced Restorative Esthetics Program, Baylor College of Dentistry, Department of Continuing Education, February 12, 1999; Dallas. 23. Spear F. The maxillary central incisal edge: a key to esthetic and functional treatment planning. Aurum Cer Den Lab News 1998;2(4):1-5. 24. Kokich V. Esthetics and anterior tooth position: an orthodontic perspective. Part II: vertical position. J Esthet Dent 1993;5(4):174-8. 25. Morley J. How to make a composite mock-up. Presented at: Accreditation Preparation Program, Baylor College of Dentistry, Postgraduate Department of Continuing Education, September 9, 1997; Dallas. 26. Eubank J. Techniques for making predictable anterior restorations. Presented at: Advanced Esthetics Continuum, Louisiana Academy of Continuing Dental Education, Louisiana State University School of Dentistry, January 7, 1996; New Orleans.
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
THE ROLE OF COSMETIC DENTISTRY IN RESTORING A YOUTHFUL APPEARANCE JEFF MORLEY, D.D.S.
he advent of new materials and technologies in dentistry during the last 30 years has brought with it the promise of a new era in restorative dentistry for the 21st century. Coupled with the profession’s aggressive pursuit of prevention and patient education is the fact that patients are keeping an ever-increasing number of teeth into advanced age.1-4 Modern restorative techniques have combined with earlier and better treatment of periodontal disease to achieve such results, and the impact of fluoridation as a caries-preventive modality also has aided in prolonging the life span of countless dentitions. The traditionally accepted role of dentist as manager of a predictable and protracted decline from repair of decay to full-coverage protection to partial or complete tooth loss has increasingly come under attack. Today, the concept of keeping most or all of one’s
A
S
T
R
A
C
T
Background. Dentistry is faced with a population that is getting older and keeping more of its natural teeth. Smiles show physical and esthetic signs of aging. Advances in the area of cosmetic dentistry now offer the dental profession new opportunities in conservative and esthetic restorative procedures that have the potential to reverse the signs of dental aging, thereby making patients appear younger. Case Description. The physical and esthetic attributes of an aged dentition are identifiable. Tooth wear over time alters the appearance of the teeth and smile in a way that is perceptible to dentists and laypeople. Bonding and adhesive ceramic restorative procedures have the potential of reversing the esthetic manifestations of the aging process for teeth. Specific diagnostic tools, including a composite resin mock-up and construction of an incisal putty matrix, allow for previsualization of possible treatment outcomes and allow clinicians to resolve occlusal as well as esthetic treatment concerns before initiating actual treatment. Clinical Implications. The ability to make patients look younger through cosmetic enhancement of teeth and smiles has tremendous implications for the future practice of dentistry. Dentists who have the training and skills to meet the increasing demand for esthetic procedures by patients seeking to restore a youthful appearance may find an expanded role within their practices for this type of treatment.
teeth for an entire lifetime has become an attainable goal. 1166
B
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
COVER STORY From a purely cosmetic standpoint, the value of the appearance of one’s teeth has taken on a greater importance in Western society. Right or wrong, the public places an increasing priority on a healthy and attractive smile. The dental profession’s traditional domain, centered around the eradication of disease, now finds itself on the threshold of uncharted territory: the enhancement of appearance. Yet, foundations of health, proper function and sound scientific principles also must prevail. As we enter the 21st century, the care of a rapidly aging population indeed may be the greatest challenge the profession will face in the years ahead.5 CHANGING DEMOGRAPHICS
The American population is getting older. A recent demographic survey indicates that more than 50,000 Americans per day are reaching the age of 50 years, and that this trend is expected to continue throughout the entire first decade of the new century.6 Additionally, the average life expectancy of Americans has been increasing at an accelerated rate. While the average life expectancy of all Americans (male and female, all races) was 35.5 years in 1798, by 1900 it had increased to 49.2 years, by 1970 to 70.1 years and by 1999 to 76 years.7 In fact, some demographers have predicted that American children born in the waning years of the 20th century my well have a life expectancy that approaches or even exceeds 100 years.7 Between 1990 and 2020, the segment of the U.S. population aged 65 to 74 years is expected to grow 74 percent.7
Figure 1. Natural dentition of a 58-year-old woman showing discoloration and visible signs of aging.
Early findings regarding this new demographic phenomenon have been predictable. Teeth that arguably may have only
The newer techniques are more esthetically pleasing and lend themselves to making cosmetic enhancements at the very same time that they restore. been designed to last 30 years in our ancestral lineage are now being called upon to last 50, 60, 70 years and beyond. Research into this expanding field has been scanty at best. A review of the literature reveals a growing interest in the subject of the aging dentition. However, the majority of pub-
lished information has focused on restorative and therapeutic opportunities created by old teeth and periodontium or on basic dental care in a medically compromised population.8-11 Almost no studies have delved into the psychologic and emotional consequences of patients’ perception of aged smiles. Furthermore, there seems to be little understanding within dentistry as to the origins and nature of a movement toward “youth at all costs” that appears to be thrusting itself on the profession. DENTISTRY’S NEW RESTORATIVE TECHNOLOGY
While cosmetic dentistry certainly has been part of the profession for centuries—even further back into antiquity than the time of George Washington’s famous prostheses12— the advent of conservative tooth restoration through bonded ceramics and resin composites literally has changed a profession’s way of thinking that has lasted well over a cen-
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
1167
COVER STORY into the “age of augmentation.”14 PHYSICAL SIGNS OF AGING IN TEETH AND SMILES
Figure 2. Patient showing classic facial esthetics of aging. Progressive wear of dentition has led to loss of vertical dimension.
Figure 3. Cosmetic reconstruction reestablishes proper vertical dimension, lip support and reveal of maxillary anterior teeth associated with a youthful smile.
tury. While still considered “new,” the dental adhesive technology introduced in 1955 by Buonocore13 is rapidly approaching its 50th anniversary. Combined with an incredible explosion in the field of dental materials, bonding has allowed for conservative restorative treatment opportunities never before dreamed possible. Porcelain veneers, non–metal-based crowns, and the ability to seal and restore 1168
teeth or fragments of teeth using adhesive materials and techniques all have shown tremendous promise and increasing reliability. These newer techniques also are more esthetically pleasing and lend themselves to making cosmetic enhancements at the same time that they restore. In fact, it has been said that bonding, in all of its various forms, has moved dentistry out of the “age of amputation” and
The esthetic manifestations of anterior tooth aging fall into three basic categories (Figure 1): dwear and the effects of erosion, attrition, abrasion and abfraction; dsize and position of teeth in relation to each other and to surrounding tissues; dcolor. Of course, other factors are associated with tooth aging that also are worthy of discussion. Teeth transform histologically and even chemically over time.15 The supporting bone and surrounding soft-tissue structures of the face undergo a metamorphosis with aging (Figure 2). As vertical dimension and lip support are lost, oftentimes the resulting muscle tension can cause soft-tissue changes in facial features away from the mouth, including the area around the eyes.16 Restoration of the aged dentition cosmetically and functionally, providing adequate soft-tissue support and tooth “reveal” (the amount of tooth or teeth showing), has the potential to make patients look younger (Figure 3).17 Wear. Wear in one form or another ultimately alters the appearance of the anterior teeth in predictable patterns that not only are recognizable by dentists but are subliminally apparent to the lay public as well.18 The most dominant force affecting tooth esthetics is abrasion, the contact of one tooth against another in protrusive and lateral function. In a typical Class I occlusion, anterior guid-
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
COVER STORY ance and “cuspid rise” will result in millions of tooth-to-tooth contacts over a lifetime. Although emphasis within the profession has been focused on the effects of bruxism and clenching, it should be noted that the visual components of these conditions are only an acceleration of what might otherwise be happening much more slowly through the aging process. Size. When compared with a more youthful-looking dentition (Figure 4), an aging dentition demonstrates the effects of specific esthetic changes that have occurred over time. The youthful smile is distinguished by its long central incisors, which typ-
Figure 4. Natural dentition of a 23-year-old woman showing typical appearance of a youthful smile.
Teeth tend to drift toward the middle of the face over time, and crowding of the dentition worsens with age. Figure 5. The intercommissure line is used as a guideline to determine proper esthetics for a youthful smile.
ically are noticeably longer than the lateral incisors adjacent to them. This gives the central incisors a distinct rectangular shape, with a width-to-height ratio in the range of 75 to 80 percent. The younger dentition also shows well-defined incisal embrasures, particularly in the maxillary anterior teeth. Incisal contact points for these teeth quite often are located at the junction of the incisal and middle thirds. As the teeth
wear down over time, not only does their width-to-height ratio change (approaching or exceeding 100 percent), but also the edges of the teeth often wear into the incisal contacts and thus wipe out incisal embrasure definition.19 Position. Changes in tooth position associated with the aging process are not easily identified. The absence of longterm tracking studies, studies using only small sample sizes
and investigators’ inability to factor out variables all have resulted in inconclusive findings. At least one recent long-term study has shown that teeth tend to drift toward the middle of the face over time, and that crowding of the dentition worsens with age.20 The position and amount of reveal of the maxillary anterior teeth also play a role in the perception of age. A useful parameter uses the amount of tooth reveal below the intercom-
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
1169
COVER STORY thickness over time, the dentin color begins to dominate tooth shades, and the teeth become progressively darker. TECHNIQUES FOR RESTORING YOUTHFUL APPEARANCE
Figure 6. Thirty-year-old patient showing more than 80 percent of maxillary teeth under intercommissure line.
Figure 7. Altered image of patient in Figure 6, with maxillary anterior teeth repositioned apically, showing how reduction in tooth reveal and inadequate amount of maxillary teeth below the intercommissure line appear to age the patient.
missure line, an imaginary line connecting the corners of the lips in a full smile position (Figure 5).21 Youthful smiles generally reveal 75 to 100 percent of the maxillary teeth below the intercommissure line. As the amount of reveal dips below 40 percent and approaches or becomes zero, the face becomes markedly aged (Figures 6 and 7). Color. As teeth age, physiologic and environmental condi1170
tions play havoc with tooth color. Although there is no evidence in the dental literature that tooth color alone plays any role in dental health, darker teeth generally are associated with older age.22 As the dental pulp shrinks, darker secondary dentin is left behind. At the same time, pigments and ions are absorbed into the teeth as a result of normal day-to-day oral habits. Combined with an ever-decreasing enamel
Simply put, any restorative, orthodontic, periodontic or surgical form of dental treatment that in some fashion counteracts or mitigates any of the esthetic attributes of an aged dentition has the potential to reverse the appearance of aging. Tooth bleaching, for example, can have dramatic youth-enhancing effects on select patients whose only problem with their otherwise healthy dentitions is that their teeth are stained, dark or yellow. The restoration of appropriate and youthful tooth length and proportion also is a treatment modality with tremendous potential. Most commonly accomplished through the judicious use of porcelain or resin composite veneers (but sometimes through the use of full-coverage bonded ceramic crowns), the restoration of tooth length lost to the predations of time or parafunctional habits can seem to turn back the clock when performed as part of a carefully thought-out treatment plan. Because the anterior teeth also are involved in the occlusal schemes for any given dentition, careful consideration of the exact length and position of the anterior teeth in the esthetic zone becomes critical.23,24 Mounting study casts on an articulator before defining a cosmetic treatment plan will give the clinician an opportunity to analyze the occlusal patterns of any patient and will
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
COVER STORY provide valuable clues as to the limits of providing a cosmetic as well as functional result. The so-called “mock-up” of a planned cosmetic treatment also has been shown to be quite useful (Figure 8). Not only can the mock-up be used to communicate potential results to the patient, but also it allows the clinician to visualize the desired results and solve potential problems before providing treatment to the patient. While the models traditionally are constructed in wax, a new technique involves fabricating the mock-up in hybrid resin composite that has been cured on a stone model.25 A simple technique calls for coating the stone model with multiple coats of any dentin adhesive and light-curing it after allowing the solvents in the adhesive to evaporate. This technique provides an adequate foundation that promotes adherence of composite resin directly to the stone model. Mock-ups made in this fashion are substantially more durable than traditional waxups and allow for fabrication of stints, registrations and guides such as the incisal putty matrix. The incisal putty matrix is the clinician’s primary registration in determining and verifying the exact position of the incisal edges of the anterior teeth during the preparation and provisionalization phase of cosmetic restorative treatment.26
Figure 8. Both the composite mock-up and incisal putty matrix are useful tools in cosmetic dentistry.
coupled with the evidence that people are living longer, are beginning to paint a compelling picture of an aging population with an increasing number of natural teeth. What will be the dental care needs of this aging
Each practitioner also must ask whether dental treatment for the purpose of restoring the appearance of youth shoud be performed.
CONCLUSION
The dental profession has done a remarkable job during the last 50 years in eradicating dental caries and educating the public in the importance of good oral hygiene. Great strides have been made toward reducing the number of teeth lost to periodontal disease. These facts,
population? If the dental profession is actively sought out by the public for the purpose of restoring a youthful appearance, will the profession be prepared? Many questions remain
unanswered or unexplored. Current techniques in cosmetic dentistry have shown great efficacy and reliability when properly used by trained clinicians. Clinicians providing this type of treatment not only must be proficient in current cosmetic techniques and materials but also must have a firm grasp of occlusal principles and a sound foundation of knowledge of basic dentistry. These considerations notwithstanding, each practitioner also must ask whether dental treatment for the purpose of restoring the appearance of youth should be performed. Who will benefit from this treatment? Who will pay for it? Will certain select members of our society be able to avail themselves of this new expanded role for dentistry while other members in need are blocked from receiving such care (by cost, by access or by both)? And what may happen if the profession holds the power to reverse the signs of the aging process when it comes to the oral environment but then chooses not to use it? At least for the moment, the
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.
1171
COVER STORY
Dr. Morley is an associate clinical professor, School of Dental Medicine, State University of New York, University at Buffalo. He also maintains a private
population that dentistry serves continues to benefit from the scientific and technological advances that have made dentistry such a remarkable profession. ■
1. Brown LJ, Swango PA. Trends in caries experience in U.S. cisco, Calif. 94123. employed adults from Address reprint 1971-74 to 1985: crossrequests to Dr. sectional comparisons. Morley. Adv Dent Res 1993;7(1):52-60. 2. Johnson BD, Mulligan K, Kiyak HA, Marder M. Aging or disease? Periodontal changes and treatment considerations in the older dental patient. Gerodontology 1989;8(4):109-18. 3. White BA, Caplon DJ, Weintraub JA. A quarter century of changes in oral health in the United States. J Dent Educ 1995;59(1):19-57. 4. Marcus SE, Drury TR, Brown LJ, Zion GR. Tooth retention and tooth loss in the permanent dentition of adults: United States, 1988-1991. J Dent Res 1996;75(special issue):684-95. practice at 1648
Union St., San Fran-
1172
5. Cunningham R. Perspectives: solution gap looms for financing baby boomers’ future long-term care needs. Med Health 1998 Mar 23;52(12)(suppl):1-4. 6. Vatter RH. Boomers enter the golden fifties. Stat Bull Metrop Insur Co. 1998;79(1):2-9. 7. Friend T, DeBarros A. Science finds no limit on life span. USA Today. March 17, 1999;Special report:5D-7D. 8. Ettinger RL. Restoring the aging dentition: repair or replacement? Int Dent J 1990; 40:275-82. 9. Iacopino AM, Wathen WF. Geriatric prosthodontics: an overview. Part 1: pretreatment considerations. Quintessence Int 1993;24:259-66. 10. Dolan TA, Mulligan R, Berkey D, Saunders MJ. Enhancing the oral health of older adults: recommendations for action. Spec Care Dentist 1996;16(6):229-36. 11. MacEntee MI. Clinical epidemiologic concerns and the geriatric prosthodontic patient. J Prosthet Dent 1994;72:487-91. 12. Fastlicht S. Tooth mutilations and dentistry in pre-Columbian Mexico. Chicago: Quintessence; 1976. 13. Buonocore MA. A simple method of increasing the adhesion of acrylic materials to enamel surfaces (abstract). J Dent Res 1955;34:749. 14. Golub-Evans J. Unity and variety: essential ingredients of a smile design. Curr Opin Cosmet Dent 1994;2:1-5. 15. Dzierzak J. Restoring the aging dentition. Curr Opin Cosmet Dent 1994;2:24-32. 16. Koury ME, Epker BN. The aged face, the facial manifestations of aging. Int J Adult Orthodon Orthognath Surg 1991;6:81-95.
17. Frush JP, Fisher RD. The age factor in dentogenics. J Prosthet Dent 1957;7:5-13. 18. Donachie MA, Walls WG. Assessment of tooth wear in an aging population. J Dent 1994;23:157-64. 19. Morley J. Smile design—specific considerations. J Calif Dent Assoc 1997;25(9):633-7. 20. Richardson ME. A preliminary report on lower arch crowding in the mature adult. Eur J Orthod 1995;17:251-7. 21. Goodkind RJ, Schwabacher WB. Use of a fiber-optic colorimeter for in vivo color measurements of 2,830 anterior teeth. J Prosthet Dent 1987;58:535-42. 22. Morley J. Advanced smile design. Presented at: Postgraduate Advanced Restorative Esthetics Program, Baylor College of Dentistry, Department of Continuing Education, February 12, 1999; Dallas. 23. Spear F. The maxillary central incisal edge: a key to esthetic and functional treatment planning. Aurum Cer Den Lab News 1998;2(4):1-5. 24. Kokich V. Esthetics and anterior tooth position: an orthodontic perspective. Part II: vertical position. J Esthet Dent 1993;5(4):174-8. 25. Morley J. How to make a composite mock-up. Presented at: Accreditation Preparation Program, Baylor College of Dentistry, Postgraduate Department of Continuing Education, September 9, 1997; Dallas. 26. Eubank J. Techniques for making predictable anterior restorations. Presented at: Advanced Esthetics Continuum, Louisiana Academy of Continuing Dental Education, Louisiana State University School of Dentistry, January 7, 1996; New Orleans.
JADA, Vol. 130, August 1999 Copyright ©1998-2001 American Dental Association. All rights reserved.