GUEST EDITORIAL Emerging paradigms in orthodontics—An essay

GUEST EDITORIAL

Emerging paradigms in orthodontics--An essay Joseph G. Ghafari, DMD* Philadephia, Pa.

Near the end of the first century of organized orthodontics, several concepts are emerging, some of which may become state of the art, while others need validation or further development. They encompass a range of areas, including the timing of early treatment, force application, modalities and outcome of treatment, research, education, and the delivery of orthodontic care.

1. TIMING OF EARLY TREATMENT Treatment in late childhood in one rather than two phases, but individual variations may require an earlier intervention. Controversy about the timing of early treatment exists at two levels of decision: 1. Treat early (in the deciduous or mixed dentition) in the belief that early intervention brings natural forces to normal function.~-4 Many questioned the advantage to be gained from early treatment and advocate treatment in the permanent dentition. 4,5 The essence of this controversy is best summarized by these statements of Edward H. Angle, that appeared in the 7th edition of his book in 19071: ...the proper time to begin treatment is as near the beginning of the variation from the normal in the process of development of the dental apparatus as possible. This may date from the eruption and locking of the first permanent molars into distal occlusion [...] or into mesial occlusion [...], or it may in rare instances have an even earlier beginning- in the mal-locking of the deciduous teeth. It has always been argued by the writers of the "old school" that this is a most unpromising age for treatment [...] favoring the period of life between the ages of twelve and seventeen years .... 2. At another level, controversy exists about the timing of early treatment itself, namely how early? In the deciduous dentition, the early, mid, or late mixed dentition? Some authors, like Angle, suggest starting therapy as early as the developing malocclusion is identified, even in the deciduous dentition. 2 Others considered intercepting a malocclusion at various stages of the mixed dentition. 68 The limitations of early treatment increase with malocclusions associated with skeletal discrepancies, particularly mesioclusions. Unfortunately, longitudinal studies establish*Professor of Orthodontics, University of Pennsylvania. Am J Orthod Dentofac Orthop 1997; 111:000-00. Reprint requests to: Dr. Joseph Ghafari, Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, 4001 Spruce St., Philadelphia, PA 19104-6003. Copyright © 1997 by the American Association of Orthodontists. 0889-5406/97/$5.00 + 0 8/1/80284

ing the value of early intervention are not yet available. Knowledge of long-term effects is needed to justify orthodontic therapy throughout childhood and possibly into early to midadolescence. The issue extends beyond severity of malocclusion to the timing of treatment, which requires, particularly in the presence of skeletal dysplasias, evaluation of dental and skeletal ages. 9 Preliminary findings of a randomized prospective clinical trial on the early treatment of Class II, Division 1 malocclusion indicate that treatment in late childhood may be as effective as that in midchildhood. ~°Thus treatment in late childhood may be more practical and cost-effective, because it reduces the total length of time a child has to be seen by an orthodontist. Actually, the results of our research 1°and that by other investigators 1114tend to concur about the value of early treatment in late childhood as the first phase of a one-stage treatment. This conclusion pertains to the correction of the distoclusion but also to space management within the dental arch. 1°, 15,16 The optimal timing of treatment in the late mixed dentition would correspond to the time just before the loss of the deciduous second molars. Nance 6 expressed similar views earlier in this century. These concepts imply that in the treatment of Class II, Division 1 malocclusion, the imperatives of dental development may dictate a timing of treatment independent of the requirements of craniofacial growth. Demirjian et a1.I7reported that dental development is not closely related to skeletal maturity or peak height velocity. They concluded that the mechanisms controlling dental development are independent of somatic and/or sexual maturity. Presumably, the correction of a skeletal dysplasia underlying a distoclusion is best achieved during active periods of growth. 9 This assumption suggests that the relationship between dental and skeletal developments must be determined in the individual patient. Extreme individual variations, such as a premature dental development relative to a normal or delayed skeletal maturation, would by necessity require early treatment to be a two-phase treatment, the first stage implemented in the mixed dentition, and the last in the permanent dentition, probably after a period of retention. Conditions that affect occlusal development or dental health would also require treatment in early or midchildhood. They include: susceptibility to trauma of the maxillary incisors because of a severe overjet, TM a functional posterior crossbite, Is,19 and developmental problems that endanger the integrity of the dental arch, le'2° such as the premature loss of deciduous teeth, particularly second molars, or the ectopic

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eruption of permanent teeth. The impact of early treatment on psychosocial development, including self-perception and self-worth, does not generally appear to warrant early intervention]3,14However, such a relationship must be monitored in the individual child. The correction of mild to moderate anterior crossbites must also be instituted in early childhood, unless the crossbite is part of a mesioclusion associated with a severe skeletal dysplasia. In this instance, the long-term benefits of early treatment are unknown and require judicious study. Finally, several craniofacial anomalies are subject to treatment regimens that include early intervention. In summary, the benefit of early treatment, particularly in avoiding extraction of permanent teeth, is no longer in question. The advantage of early treatment and its timing in indiVidual patients may be questionable. Hence early treatment, and further studies of its effectiveness, should be focused on individual variation (see section 7- Research).

2. ORTHODONTIC FORCES Light intermittent forces may be optimal for tooth movement. Light continuous forces seem to be the state of the art of orthodontic mechanotherapy. Interrupted orthodontic forces have also been shown to produce tooth movement similar to that generated by continuous forces with less damage to the structures of the periodontal ligament,zl In a series of experiments, King and his associates 21-24tested the relationship between force magnitude, duration, and frequency. Several conclusions emerged that supported previous research findings by other investigators, or suggested new qualifications for orthodontic forces. Light short-term or cyclic force applications can alter tooth position in a way comparable to light continuous forces. Significant amounts of bone turnover and remodeling events consistent with the direction of loading, and associated with tooth movement, continue for an indeterminate period after appliance decay, or appliance removal. 24 These findings are consistent with the findings of Rubin and Lanyon25that minimal exposures 'to forces at physiological levels (four consecutive loading cycles per day totaling 8 seconds) could stimulate bone modeling (inhibitingresorption) significant enough to prevent disuse osteoporosis in immobilized avian wings. In a series of experiments, z5-3°they removed the epiphyseal ends of the ulna in turkeys and roosters, thus freeing the remaining diaphysis from any regular functional strains. The vascular and nervous elements entering the bony shaft were left intact. Stainless steel pins were then inserted into each end of the bone, protruding through the skin, and permitting the application, at different magnitudes and frequency, of mechanical loads to the ulna. In the absence of any applied stress, gradual loss of bone mass occurred, 2vwhile the daily application of four loading cycles maintainedbone mass. In contrast, continuous loads had no effect on the ulnar modeling and caused resorption. However, when such loads were applied intermittently for only a few minutes daily, bone mass increased substantiallyY The degree and nature of bone remodeling was directly related to the magnitude of applied bone

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strain, demonstrating the existence of a threshold of force magnitude necessary for enhanced osteogenesis on both periosteal and endosteal surfaces. 26Similar interactions between force applications and bone remodeling response are at play in orthodontic tooth movement. To explain these biologic responses, Skerry et al.28proposed that the large proteoglycan molecules are a likely stress-sensitive element in bone matrix. This group observed a strain-mediated change in the direction of the proteoglycan molecules, which needed almost 48 hours to regain their original threedimensional tree-like configuration. Thus a strain memory is described as strain is maintained in bone matrix long after removal of the externally applied stress. Seemingly, bone cells most affected by matrix strain are the osteocytes, which, in turn, through cell-cell communication mediated by gap junction protein (connexin 43), can activate bone surface cells. 29,3° Different ranges of optimal orthodontic forces have been described (20 to 26 gm/cm2 according to Schwartz; 31 83 gin/ cm2 according to Miura32). Even the lighter forces may cause large strains in the periodontal ligament, perhaps inducing an injury rather than an "adaptive" response. Research by Rubin, Lanyon, and their associates regarding force magnitude would suggest that smaller strains (<100 B~ ) than currently used may be appropriate for tooth movement, if induced at the right frequency (Hz). Recently, Tuncay et al? 3 suggested that ultrasound waves, applied for relatively short periods of time, mimic the inflammatory conditions in the gingival tissues necessary for orthodontic tooth movement. The impact of the research by King and his associates, and the support and probable explanations provided by the work of Rubin, Lanyon, and their associates, challenge the present dogma that advocates the use of light continuous forces for tooth movement. Instead, light intermittent or interrupted forces would be needed for physiologic movement. The method of application of these forces would be altered from current appliances. However, although examples abound to illustrate the effect of short-term light forces on tooth position, judicious clinical research is needed to test this hypothesis. All the reported evidence was gathered from animal research. As stated by Davidovitch,34several questions must be answered: (1) Are occlusal forces detrimental to short-term orthodontic forces? (Because in the experiments of King and his associates, these forces were eliminated by the extraction of teeth opposite the investigated teeth). (2) Is there evidence of strain memory in the alveolar bone or, particularly, in the periodontal ligament? If these questions, along with clinical research, support the concept of short-term application of light forces, orthodontic treatment as we know it today will be significantly modified. Presumably, a single, short period of low-amplitude strain stimulus rather than the continuous, large signal would effect tooth movement. The intermittent application of orthodontic forces may not be practical to both patient and orthodontist; however, technologic developments with families of "smart" wires and other attachments should accommodate the requirements of intermittent pressure if it emerges as the optimal method of treatment. An outgrowth of this theorem would be

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the avoidance of some complications of orthodontic treatment (such as root resorption, loss of anchorage) with light intermittent forces that would favor direct surface resorption and minimize hyalinization and its side effects.

3. CAMOUFLAGE AND ADJUNCTIVE SURGERY Limited compensation short of the ideal surgical treatment, and of a Class I occlusion, may be the appropriate camouflage as the severity of skeletal discrepancy increases. Treatment of malocclusions underlined by skeletal discrepancy ranges from dentoalveolar compensation or camouflage to adjunctive orthognathic surgery. The basic idea of camouflage involves extraction of teeth to correct molar and incisor relationships of a Class II or Class III malocclusion, despite the underlying jaw discrepancy. Orthodontic camouflage implies a favorable, at least nondetrimental effect on facial esthetics. 35 A long-prevailing tenet among orthodontists is that achieving a Class I occlusion is a measure of success, although in many instances this goal is reached at the expense of facial esthetics. In the last decade, the pendulum has swung toward adjunctive orthognathic surgery as the only, albeit ideal, alternative to camouflage, if facial esthetics were to be improved or not worsened by excessive compensatory tipping of teeth. An emerging concept may be termed limited compensation (for proper camouflage). In essence, it is treatment toward, but not necessarily achieving Class I occlusion, commensurate with favorable facial appearance, if the patient does not opt for the ideal surgical treatment or, as is increasingly the situation, insurance coverage for the surgery is denied. This concept implies that, in a Class II malocclusion for example, an excessive overjet is only partially reduced to avoid "flattening" the profile by inordinate dentoalveolar compensation. If teeth are extracted to maximize compensation and should the patient decide to undergo surgery later in life, decompensating the compensatory inclinations of the teeth becomes a task that is both more demanding and prone to more therapeutic side effects such as root resorption. Therefore limited camouflage or limited dentoalveolar compensation involves, perhaps as much as any therapeutic approach, the recognition of individual treatment objectives and limitations. The challenge for the clinician is to reach an educated decision to balance individual diagnosis and expectations with the anticipated outcome and side effects of treatment, including a serious consideration of the benefits and risks (compromised esthetics, root resorption, bone fenestration, gingival recession, lengthy treatment) of alternative approaches (see section 9).

4. THE THREE-DIMENSIONAL FACE AND OCCLUSION Beyond Angle's classification, achieving a multidimensional balance. Cephalometrics is a needed tool in orthodontics, but historically has been restricted to the sagittal view of the face, perhaps reflecting the clinician's emphasis on the sagittal deviations of the dentition according to Edward Angle's classification? 6 Yet information from the frontal view is particularly important to integrate in the formulation of a proper di-

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agnosis for the individual patient, because "man meets his fellow men in frontal confrontation. ''36 The increased awareness of the multidimensional nature of face and occlusion has led to a cycle of nonextraction treatment and to further consideration of arch expansion, at times requiring orthopedic means, including surgically assisted palatal expansion in nongrowing patients. As with most therapeutic cycles, the pendulum tends to swing too far in one direction, but two basic principles are offered as the rationale for arch expansion: space creation and esthetic consideration. The latter pertains to the relationship between a narrow maxillary arch and the smile. A space between the maxillary lateral teeth and the corner of the lips during smile appears as a black or dark space, or "corridor," and may detract from facial attractivenes; the way a flat profile does. A narrow maxillary arch may result from orthodontic therapy, particularly when maxillary teeth (often premolars) are extracted. On the other hand, widening of the maxillary arch through orthodontic and/or orthopedic means, as may be indicated, may enhance the esthetics of a smile. The argument about extraction of teeth for orthodontic alignment is clearly related to the issue of arch expansion and is reminiscent of older debates throughout the history of orthodontics. Edward Angle's statements about the issue in 1907, discussed in the context of facial esthetics, reflect the lasting controversy37: ...the best balance, the best harmony, the best proportions of the mouth in its relations to the other [facial] features require that there shall be the full complement of teeth, and that each tooth shall be made to occupy its normal position-normal occlusion .... [the] unfortunate and inartistic results [of extraction] may be seen in every community. It is gratifying, however, that this fallacious teaching and pernicious practice are rapidly passing .... At issue is balancing in the individual patient, the esthetic requirements with the requirements of function, stability, and periodontal health. Extraction of permanent teeth may be required to achieve this balance. The goals and limitations of dentoalveolar compensation or camouflage, discussed for the sagittal and vertical planes, apply in the frontal dimension as well.

5. USE OF PHARMACEUTICAL SUBSTANCES TO EFFECT ROOT RESORPTION, TOOTH MOVEMENT AND ANCHORAGE Local application may be problematic, but investigation is proceeding. Root resorption. Root resorption is a common occurrence during orthodontic treatment that varies from microscopic to serious macroscopic levels. Root shortening is unpredictable, and the level of loss of tooth substance may not be anticipated with certainty on the basis of any of the reported etiologic factors acting separately or in combinations. Furthermore, the root resorption process varies not only among persons, but also within the same person at different times, 38 as well as between different teeth in the same person. 39 Among several solutions advanced to decrease the risk of occurrence of root resorption was the possibility of arresting

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root resorption by injecting substances that may inhibit the resorptive process near the involved roots. 39The basis for this suggestion is that a considerable number of cytokines and growth factors have been examined that modulate the activity of both the osteoblast and osteoclast. 4° Inhibition of osteoclastic activity and up-regulation of osteogenesis may act together to shift the equilibrium between osteoclastic and osteoblastic activities away from resorption. A similar mechanism may apply in the external root resorption model. Although such a mechanism has not been explored, the systemic administration of 0.5 gm Thyroid (Proloid, Parke Davis) was reported in three patients by Loberg and Engstr6m.4~ The maxillary incisors in all patients were subjected to intrusion and lingual root torque. In a commentary on this report, Christiansen42suggested that thyroxine administration, instead of lowering the frequency of root resorption, may have increased the rate of alveolar bone resorption, thus indirectly decreasing root resorption. This report should not be an invitation to start using thyroxine, albeit in minute amounts, to reduce root resorption. Thyroxine reduces bone mass, and the substance used in the reported patients is a bovine product whose effectiveness may be questionable. Yet the basic premise of using substances that alter the biologic response to tooth movement seems to be a trend for at least future investigation. Recently, Davidovitch43 suggested that the consumption of alcohol may be related to root resorption during orthodontic treatment in adults by inhibiting the hydroxylation of vitamin D in the liver. The contribution of systemic conditions, acting in concert with local factors, would need careful exploration. Anchorage and tooth movement. In a series of experiments, the topical administration of a potent blocker of bone resorption, biphosphonate (risedronate), caused a significant and dose-dependent reduction of tooth movement, and inhibited relapse of tooth movement in rats. 44These experiments suggest that the topical, not only systemic, application of risedronate may be helpful in anchoring and retaining teeth during orthodontic treatment. Tetracycline may have a similar potential while presenting less side effects, since it may be used in its nonantimicrobial form (analogue).45 Other substances have been investigated that may affect the rate of tooth movement, including prostaglandin46'47and vitamin D. 48,49 The routine use of topical substances as an aid in tooth movement, retention, and avoidance of root resorption undoubtedly requires more research and definition. A basic problem for the application of such concepts in human beings is dispensing these substances locally with minimal discomfort to the patient. Although application in human beings may not be imminent, the concept is gaining momentum for investigation.

6. T E C H N O L O G I C A L AND T H E R A P E U T I C ADVANCES "Smart" wires, glass ionomer, computerization, implants, distraction osteogenesis. Technologic advances always have the potential to generate shifts in paradigms. Several can be listed that affected the

American Journal of Orthodontics and Dentofacial Orthopedics May 1997 development of orthodontics to this day: the advent of the edgewise bracket, bonding, glass ionomer cements, cephalometric radiography, video imaging, the use of computers to help in treatment planning and practice management, programmed (prescription) brackets, nickel titanium or other alloy wires, and rigid fixation in orthognathic surgery. Although most developments for several decades have been variations on preexisting technology, it is equally true that major changes in orthodontic therapy have been dictated by industries behind such developments. At present, the advances that may potentially affect a new direction in orthodontic treatment relate tO implants and bone lengthening. The use of implants to assist as anchorage units during tooth movement is still at developmental or experimental stages) ° Onplants, small surface-retained implants, may emerge as the method of choice in orthodontics,51 although their use will probably be limited to select conditions. Bone lengthening through distraction osteogenesis, now in use in the treatment of craniofacial anomalies, 52,53may emerge as an orthopedic adjunct to orthodontic treatment of malocclusions. The device used to lengthen bones is an extraoral configuration. Successful mandibular lengthening with intraoral devices was reported recently in primates, 54and applications in human subjects will undoubtedly follow, possibly leading to the resolution of mandibular retrognathism through this osteogenic approach. This premise, however, will require extensive research, including the exploration of advantages and disadvantages of correcting the skeletal problem through surgery versus osteogenesis. Although both procedures affect bone structure, the surrounding soft tissue envelope may be the critical limiting factor in success and stability of treatment.

7. RESEARCH More clinical research;focus on individual variation; integrating biology in understanding and monitoring clinical advances. Trends in craniofacial research are changing primarily in favor of more clinical research than before. Kinsey and Kremenak55 reported a sixfold increase in clinical reports at the meetings of the American and International Associations for Dental Research (AADR, IADR) between 1966 and 1992, from 4% to 24%, respectively. Cell and molecular biology, genetics and inheritance, growth and development, structure, and physiology make up the rest of research areas. The significance of clinical research in orthodontics is further emphasized by the funding National Institutes of Health (NIH) provided for clinical trials to investigate the efficacy and efficiency of alternative approaches in the treatment of malocclusions. Three prospective studies of the early treatment of Class II, Division 1 malocclusions, two trials (one prospective, one retrospective) on treatment with or without extraction of teeth, and one study on measures of treatment outcome were the first cohort of clinical trials to use rigorous designs?6 The prospective investigations involved random assignment of patients to treatment groups to eliminate selection bias. Furthermore, the debate has shifted from evaluating the shortcomings of retrospective and prospective studies

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to the potential contribution of each. In 1994 and 1995, three symposia at the IADR and AADR meetings were an adequate forum for this debate. A major byproduct of all these efforts and activities is that the debate generated a focus on proper scientific research method (design and conduct), irrespective of the individual contribution of the various projects. This focus enhances scientific discourse and its impact on orthodontic education, if properly channeled through orthodontic programs and organized orthodontics, is immeasurable. The shortcomings of retrospective and prospective investigations have increased the awareness for standardizing orthodontic records to organize a registry or data bank that would be the basis for investigating major clinical questions?7 The standard of peer review has necessarily been raised by the debate, and a new culture of increasingly more sophisticated investigative procedures is infiltrating education through communication of rigorous methods and designs of investigation. Moreover, the nature of the debate has shifted from summary discussions of variability in studies accounting for average responses to the concept of discovering and characterizing individual differences. 58 As clinical research increasingly adapts to rigorous methodologic and statistical precepts, treatment results are mostly evaluated with morphometrics, namely, measurements through cephalometric roentgenography, the vernier caliper, and lately the digitizer.59 The findings represent descriptive two-dimensional analyses, and some understanding of facial growth and its modification by orthodontic and orthognathic treatment, through cross-reference with findings from experimental studies. Although the method of evaluating growth and treatment has improved, more sophisticated tools that explore the craniofacial complex need to be developed to revisit and address standing issues, particularly the behavior and response of soft tissues to changing environmental conditions. In the meantime, universal standards must be adopted for existing technology, starting with the adoption of a global standard film-to-object distance in cephalometry, or at least the correction for radiographic enlargement, particularly when data from different sources are compared. Advances in molecular biology and its impact on knowledge of cellular physiology will undoubtedly help understand growth processes and therapeutic responses. The underlying mechanisms of tooth movement and root resorption are rooted in biology, and understanding these mechanisms, which can only emerge from sound basic biologic research, will ultimately affect the choice of mechanotherapy. This realization is enhanced by the increasing emphasis on more medically oriented education.59,6°Interestingly, a burgeoning trend is the integration of basic biologic research and clinical research, clearly illustrated by the attempt to gauge therapeutic progress through biologic means. This premise is well documented in the analysis of crevicular fluids to detect biologic factors, such as two potent bone resorbing mediators, interleukin (IL) 1~61,62 and prostaglandin E 62, to evaluate the progress of tooth movement in the individual patient; or in the analysis of hormones, such as the androgen hormone dehydroepiandrosterone sulfate

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(DHEAS), 1°to assist in timing treatment or understand the contribution of growth to specific treatment modalities, j°

8, EDUCATION Stated goals to educate scholarly clinicians are contradicted by the decline of the full-time academician and other consequences of economic pressure and institutional politics. The specialty of orthodontics seemingly requires a different approach to treatment, education, and research than the rest of dentistry,63but the debate about orthodontic education mirrors the general debate about dental education. At the end of the twentieth century, both dental6° and orthodontic63education are estimated to be at Crossroads. Because minimal requirements are defined by the Council on Dental Education and enforced by accreditation reviews, the basic argument is whether the definition of "minimal competency" is, in practice, commensurate with education rather than technical training. In this context, research has become a "requirement" for graduation from almost all orthodontic programs in the United States. 63If properly dispensed, this requirement would favor a trend toward scholarly education, because it assumes and should provide an in-depth venture into an array of scientific topics. The debate has inevitablyencompassed the definition of educational "models," specifically the "dental" or "orthodontic" model versus the "medical" model. The latter usually reflects learning through the interaction of residents with attending staff and other residents in a hospital setting. In this environment, the scholarly acumen does not necessarily prevail over the clinical competence; yet there is a basic assumption that biology is not disengaged from clinical activity, even in the pure surgical model, which tends to be more closely associated with the mechanically oriented dental model. From a therapeutic point of view, the analogy is more appropriate between orthodontics and orthopedics. 63 Little attention, however, is paid to tissue biomechanics. In reality, the definition of education, in contrast with training, transcends the differentiation between models. The difference is in the quality and depth of study, which should indeed involve treatment of a variety of malocclusions, but not at the expense of comprehensive understanding and study of the individual characteristics and needs of a patient, as well as the underlying principles of biology and mechanics that facilitate therapy. Many clinicians, including academicians, view basic research as marginal, even irrelevant, to the education of orthodontists, thus unwillingly but effectively divorcing clinical action from biologic responseY This problem may be related to dentists in general, starting with training in dental schools. The implication of comparing the educational models is that the curriculum of specialty orthodontics must keep pace with advances in biomedical science because specialty education, rather than training, is the objective. Therefore the emerging paradigm in education is the stated need to integrate models for one goal: educate scholarly clinicians, proficient in diagnosis and treatment, yet understanding and appreciative of the scientific method of clinical investigation, as well as the underlying biology of growth, tooth movement,

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and related sciences. 63To achieve this goal, a trend to longer postdoctoral training in orthodontics has begun, with almost a third requiring 3 years of study, given the skills and scope of knowledge necessary for education and clinical competence, particularly when a Masters degree is sought in conjunction with orthodontic certification. The challenges that run counter to this goal are the increasing difficulty to secure funding for research, high tuition, and a decline in candidates for full-time academics, or failure to retain them, in the face of an ever-increasing demand for orthodontic education by high ranking dental graduates. The major factors responsible for the loss or decline in number of competent full-time academicians include debt from prior education; pressure to overproduce by combining the requirements of (funded) research, peer reviewed publication, clinical and didactic teaching, and intramural practice; politics, whose scope includes indictments of entrenched self-protective leadership and expedient institutional acceptance or protectionism.63 These challenges help to shift emphasis from education to training. Moreover, when dental schools draw resources contributed by orthodontic departments away from these divisions, they favor the growth of competing institutions that offer reduced tuition and/or stipends, including hospital training programs. These institutions stand to attract the brightest crop of students and, if a research environment is facilitated, most productive teachers.

9. ORTHODONTIC SERVICES/OUTCOME MEASURE Pressures to compromise treatment results versus ideal standards of care. Three panels must be considered that relate to emerging trends in orthodontic healthcare: the variable delivery systems, the doctor-patient relationship, and the implications of outcome measures on individual treatment and public health in general. Orthodontic care. The state of orthodontic services was best summed up in this statement at a conference that evaluated contemporary trends in orthodontics~9: Clinicalpractice has become inundated in a world of[... ] managed care organizations, insurance reporting, peer review, malpractice insurance, Occupational Safety and Health Act (OSHA) regulations, guidelines for Disease Control (CDC), competition from non-specialists in orthodontics, risk management and changes in the patient-doctor relationship. This listing may seem overwhelming and yet reflects the orbit of contemporary heaIthcare in general. Government regulators and insurance companies all over the world determine more and more and even dictate what, where and when, as well as how medical and also dental and orthodontic treatment can and should be provided. Another trend in the delivery of orthodontic care is the increasing number of group practices relative to solo practices. This trend is primarily the result of large financial debts young graduates face that steer them into association with established practitioners. Group practice includes several benefits: interaction with more experienced clinicians, guidance

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in patient handling, and business organization. Commercial undertones, however, are tangible. Not only is cost-effectiveness promoted, but the focus on increasing the volume of patients carries the pressure of compromising treatment results and/or lengthening treatment duration. Doctor-patient relationship. One of the outgrowths of the commercial model is the shift in the doctor-patient relationship, from the paternalistic "guild" model, to the interactive format of a partnership,64albeit that this relationship becomes increasingly impersonal with a larger volume of patients. Informed consent and risk management to avoid malpractice claims are already an integral part of healthcare in general and enforce a sense of responsibility for optimal treatment planning and patient care also in orthodontics. At least two consequences of this shift are noted: Compromised results are presented as alternative approaches in contrast to the ideal option, and general dentists who provide orthodontic treatment and are conscious of potential malpractice litigation, tend to delegate such treatment to orthodontists associated with their practice on a part-time basis. Outcome measures. Initial data from measures of treatment outcome indicate that orthodontists expect more consumer inconvenience and greater esthetic benefits than the consumers themselvesY In fact, it may be argued that from the point of view of patients, limited treatment yields acceptable results faster, while orthodontists would rate these results as inadequate. If these observations are borne through more definitive research, the question would arise whether "compromised" treatment results, short of the "ideal" neutroclusion with appropriate inclinations of teeth, should represent an acceptable goal. In view of the decrease in thirdparty payment for orthognathic surgery, the financial pressures also direct toward acceptance of compromised treatment by established orthodontists, notwithstanding the fact that this option should be recognized as only less than ideal during specialty education. In this instance, nonorthodontists may venture again in rendering orthodontic treatment, reversing the apparent present trend of delegating the treatment to specialists. The previous panels point to a potential conflict in the development of orthodontic care. The standard of care has been improved in the last 30 years, owing to an explosion of informationthrough research, surgical advancement, and product development.63 Yet the quality of care varies (and is not carefully monitored), because of financial and commercial pressures, compounded with outcome measures that may promote expediency at the expense of optimal occlusion, an increasingly impersonal relationship between health provider and patient, and possibly the failure of clinicians to constantly update their method with current concepts and new materials. The emerging trend in this contradictory environment is the realization that the solution to the conflicting realities is not a uniform program for cook book treatment, but universal standards of care, ethics, and education that are beyond any reproach, and that can only be elevated by the level of commitment to these values in daily endeavors.63 Countries and geographic entities are institutionalizing such standards and

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organizing in corresponding Boards (European, Australian). The idea of a global World Board of Orthodontics66is now a realistic project already under intense debate. However, the open question in this paradigm is the definition of an individual standard, in that the concept of an individual norm for each patient must be explored. Furthermore, ideal standards can be applied to people with financial means, while compromised when financial resources are not available. This development, in turn, will affect the patterns of education, depending on whether and what percentage of patients seeking treatment in orthodontic departments opt for compromised therapy. Compromised results, if not regarded as only a secondary option, may become institutionalized and accepted. The danger lies in adopting such results at the expense of recognized optimal standards of care that are fitted to the functional and esthetic needs of the individual patient, particularly by orthodontists who ignore these standards or compromise them after Board certification. REFERENCES 1. Angle EH. Treatment--preliminary considerations. In: Angle EH, editor. Malocclusion of the teeth. 7th ed. Philadelphia: SS White Dental Manufacturing Co., 1907:309-13. 2. De Baets J, Joho JP, Schatz JP. The Geneva Plate-Headgear appliance: early treatment of severe Class II open-bite cases. 62nd Congress. Eur Orthod Soc 1986:87. 3. Grosfeld 0, Migdalska-Chojecka M. Interception of malocclusion in the deciduous dentition: long-term results. Am J Orthod 1978;73:73-8. 4. Hahn GW. A panel on treatment in deciduous dentition. Am J Orthod 1955;41:25561. 5. Barich FT. Treatment in the mixed dentition period. Am J Orthod 1952;38:625-33. 6. Nance HN. The limitations of orthodontic treatment. Am J Orthod Oral Surg 1947; 33:177-223,253-301. 7. Freeman JD. Preventive and interceptive orthodontics: a clinical review and the resuits of a clinical study, f Prey Dent 1977;4:7-23. 8. Ackerman JL, Prnffit WR. Preventive and interceptive orthodontics: a strong theory proves weak in practice. Angle Orthod 1980;50:75-87. 9. Bj6rk A. Timing of interceptive orthodontic measures based on stages of maturation. Trans Eur Orthod Soc 1992:61-74. 10. Ghafari J, Shofer FS, Laster LL, Markowitz DL, Shofer FS, Silverton S, et al. Monitoring growth during orthodontic treatment. Semin Orthod 1995;1:165-75. I I. Gianelly AA. One-phase versus two-phase treatment. Am J Orthod Dentofac Orthop 1995;108:556-9. 12. Livieratos FA. Class II treatment: a comparison of one- and two-stage non-extraction alternatives. In: McNamara JA Jr, editor. Orthodontic treatment: outcome and effectiveness. CraniofaciaI Growth Series. Ann Arbor: Center for Growth and Development, University of Michigan, 1995:163-93. 13. Keeling SD, King GJ, Wheeler TT, McGorray S. Timing of Class II treatment: rationale, methods, and early results of an ongoing randomized clinical trial. In: McNamara JA Jr, editor. Orthodontic treatment: outcome and effectiveness. Craniofacial Growth Series. Ann Arbor: Center for Growth and Development, University of Michigan, 1995:81-1 I2. 14. Tulloch JFC, Phillips C, Proffit WR. Early versus late treatment of Class II malocclusion: preliminary results from the UNC clinical trial. In: McNamara JA Jr, editor. Orthodontic treatment: outcome aud effectiveness. Craniofacial Growth Series. Ann Arbor: Center for Growth and Development, University o f Michigan, 1995: i 13-38. 15. Gianelly AA. Crowding: timing of treatment. Angle Orthod i994;64:415-8. I6. Gianelly AA. Leeway space and the resolution of crowding in the mixed dentition. Semin Orthod 1995; 1: 188-94(special issue). 17. Demirjian A, Buschang PH, Tanguay R, Patterson DK. Interrelationships among measures of somatic, skeletal, dental, and sexual maturity. Am J Orthod 1985;88:433-8. 18. Myers DR, Barenie JT, Bell RA, Williamson E. Condylar position in children with functional posterior crossbites: before and after crossbite correction. Pediatr Dent 1980;2:190-4. 19. Hesse KL, Artun J, Joondeph DR, Kennedy DB. Condylar position and occlusion associated with functional posterior crossbite. J Dent Res 1996;75:123(Abstr. 842). 20. Ghafari J. Early treatment of dental arch problems, I: space maintenance, space gaining. Quintessence Int 1986;17:423-32. 21. Gibson JM, King GJ, Keeling SD. Long-term orthodontic tooth movement response to short-term force in the rat. Angle Orthod 1992;62:211-5. 22. King GJ, Keeling SD. Orthodontic bone remodeling in relation to appliance decay. Angle Orthod 1995;65:129-40.

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61. Tzannetous S, Efstratiadis S, Herrera-Abreu M, Nicolay O, Grbic J, Lamster IB. GCF levels of IL-I~ and ~G during orthodontic treatment. J Dent Res I996;75:144(Abstr. 1011). 62. Grieve WG, Johnson GK, Moore RN, Reinhardt RA, DuBois LM. Prostaglandin E (PGE) and interleukin-1 beta (IL-lbeta) levels in gingival crevicular fluid during human orthodontic tooth movement. Am J Orthod Dentofae Orthop 1994;105:36974. 63. Moorrees CFA, Ghafari J. At crossroads. In: Ghafari JG, Moorrees CFA, editors. Orthodontics at crossroads. Boston: The Harvard Society for the Advancement of Orthodontics, 1993:249-52. 64. Ackerman JL. Ethics and risk management in orthodontics. In: Ghafari JG, Moorrees CFA, editors. Orthodontics at crossroads. Boston: The Harvard Society for the Advancement of Orthodontics, 1993:49-60. 65. Miehaels C, Bennett M, Weyant R, O'Brien K, Vig KWL. Comparing orthodontist and consumer expectations of orthodontic treatment. J Dent Res 1994;73:443(Abst. 2731). 66. Dale JG. The American Board of Orthodontics. In: Ghafari JG, Moorrees CFA, editors. Orthodontics at crossroads. Boston: The Harvard Society for the Advancement of Orthodontics, 1993:25-34.

AAO MEETING CALENDAR 1998 - Dallas, Texas, May 16 to 20, Dallas Convention Center 1999 - San Diego, Calif., May 15 to 19, San Diego Convention Center 2000 - Chicago, II1., April 29 to May 3, McCormick Place Convention Center

(5th IOC and 2nd Meeting of WFO) 2001 2002 2003 2004

-Toronto, Ontario, Canada, May 5 to 9, Toronto Convention Center - Baltimore, Md., April 20 to 24, Baltimore Convention Center - Hawaiian Islands, May 2 to 9, Hawaii Convention Center - Orlando, Fla., May 1 to 5, Orlando Convention Center