Update

Treatment Planning in the 21st Century: What’s New?

Donald A. Curtis, DMD; Alton Lacy, PhD, DDS; Ray Chu, DDS; David Richards, DDS, PhD; Octavia Plesh, DDS, MS; Paul Kasrovi DDS, MS; and Rich Kao, DDS, PhD

Copyright 2002 Journal of the California Dental Association.

About the Authors:

Donald A. Curtis, DMD, is a professor in the Department of Preventive and Restorative Dental Sciences at the University of California at San Francisco School of Dentistry.

Alton Lacy, PhD, DDS, is a clinical professor in the Department of Preventive and Restorative Dental Sciences at UCSF School of Dentistry.

Ray Chu, DDS, is in private practice in Cupertino, Calif.

David Richards, DDS, PhD, is in private practice in San Diego, Calif.

Octavia Plesh, DDS, MS, is a professor in the Department of Preventive and Restorative Dental Sciences at UCSF School of Dentistry.

Paul Kasrovi, DDS, MS, is in private practice in Berkeley, Calif.

Rich Kao, DDS, PhD, is in private practice in Cupertino, Calif.

Many variables affect treatment planning, and it is important for clinicians to consider why they plan certain procedures for patient care. New materials, technologies, and products are constantly being introduced and affect decision making in dentistry. In addition, patients are more informed, have higher esthetic concerns, and want a greater stake in treatment planning decisions than ever before. How dentists treatment plan needs to reflect the many influences on final treatment outcome. The purpose of this paper is to outline how treatment planning has changed in dentistry with the goal of providing the general dentist updated information to develop a cohesive treatment plan.

Treatment planning for dental patients involves consideration of the many variables that affect the final outcome. Variables to consider include the procedure selected, the restorative material used, the influence of one treatment on another, the availability of specialized expertise, the projected longevity of treatment, the functional and psychological satisfaction achievable, the ability of the patient to maintain the results of treatment, the affordability of the services, and the individual clinician’s skill and support. A successful treatment plan balances all of these factors.

Treatment planning has become increasingly complex because the patient often requires multifaceted and sequenced care and because more patients have high esthetic expectations. Often, several specialties need to be coordinated over an extended period to manipulate the hard and soft tissues for optimal results. Additionally, the number of treatment options for a given dental problem has dramatically increased. Successful treatment planning must carefully consider the numerous influences on treatment outcomes, incorporate dental advances, and sensibly attempt to fulfill the wants as well as the needs of the patient.

The purpose of this review is to provide the general practitioner with a synopsis of how treatment planning has changed in the past decade. Scientific advances and the impact of those advances in the areas of biomaterials, prosthodontics, periodontics, and orthodontics will be outlined with the goal of providing updated information so the general dentist can develop a more cohesive treatment plan.

General Considerations

The approach used by clinicians to develop treatment plans changes throughout their careers and is influenced by factors clinicians can control, such as the gathering of clinical information or the choice of specialists available, and those they have less control over, such as insurance payments or the affordability of treatment. Treatment planning for recent graduates is most influenced by the materials and techniques taught in dental school. Dental school training offers a conservative but predictable approach for many clinical procedures and provides a foundation for future professional growth. Initial training is modified by clinical experience, continuing education, study clubs, new product development, and treatment successes and failures.

Treatment planning has traditionally been specialty-based using different classification systems that make a comprehensive plan difficult to integrate. For example, classification in periodontics focuses on degree of disease (gingivitis versus periodontitis) while prosthodontics is related to anatomic classification (Kennedy Class I versus Class II) and orthodontics to tooth and arch relationship (Angle Class I vs. Class II). Because specialties focus on specific aspects of treatment and classify patient data differently, an integrated treatment plan that provides a measure of complexity is lacking. Some classification systems have been developed that classify clinical findings according to complexity, allowing better integration of specialty data, but these classification systems have not been widely accepted.^1,2

Treatment planning and acceptance of a plan are influenced to a large degree by the cost of treatment and corresponding insurance coverage. The proposed treatment must be affordable to the patient and remunerative to the provider. In many situations, the sequencing of treatment is staged to maximize insurance coverage. While staged or quadrant dentistry has become the norm for treating patients who want to maximize insurance benefits, it does not always reflect the ideal approach or proper treatment sequence. For example, a patient with extensive dental needs and limited insurance benefits may desire to have the more visible anterior crowns completed first although the posterior crowns may have a higher functional priority. Treating the anterior teeth first may be a mistake, especially if the patient does not follow through with the posterior crowns. The Dentists Insurance Company has stated that malpractice suits have occurred in clinical situations equivalent to the above example.³ A rational treatment plan cannot be subverted to meet unrealistic patient demands or to maximize insurance benefits.

The public perception is that dental insurance should pay for the treatment of dental diseases; however, the reality is that most insurance plans provide inadequate benefits for effective treatment of dental diseases, whether the treatment is innovative or even considered the standard of care like implants. The increase in the number of insurance plans and third-party payers clearly influences (and will continue to influence) the treatment planning process, irrespective of all other factors outlined in this article.

Treatment planning has been influenced by a changing patient/clinician relationship as well as by media messages that promote and highlight cosmetic dental care. The interaction between the clinician and patient in developing a treatment plan has changed because the patient is often more knowledgeable about treatment options and often wants some degree of ownership in treatment decisions. Although the historically autocratic outline of treatment options from the clinician is still acceptable in certain situations, most patients want a collegial discussion to develop a treatment plan.

The public is told in subtle and not so subtle media messages that an attractive smile is not solely the product of genetic good fortune, but rather can be developed through creative dental treatment. Television and advertisements in popular health and beauty magazines promoting the use of tooth whitening agents has heightened public awareness of the cosmetic benefits of dental care. These media messages make it clear to consumers that contemporary dental treatment goes beyond the management of dental disease. Images of models with beautiful, well-aligned white teeth adorn the covers of the popular magazines that decorate the supermarket checkout areas. Dental practices that include esthetic procedures in addition to traditional therapies for managing dental diseases draw from an expanding menu of treatment options. Dental "wants" now compete with dental "needs" for the dentist’s time and effort. The upshot of this trend is greater patient involvement, interest, and knowledge of treatment possibilities, which requires the dentist to carefully counsel patients on a prudent treatment plan.

Biomaterials and Treatment Planning

In the past decade, dentists have witnessed a virtual explosion of new materials and improved dentin bonding; and they have gained a better understanding of materials biocompatability. The public’s desire for tooth-colored restorations, coupled with continuing fears, justified or not, about adverse effects of dental amalgam restorations, has led to the development of durable composite resins and effective techniques for direct placement of these materials in posterior teeth. Contemporary composites are strong, durable, and no longer seen as inferior restorations for posterior teeth in selected situations. The potential of modern composite materials to strengthen teeth that have been weakened by previous amalgam restorations makes them both visually and functionally attractive treatment options.

A more conservative treatment planning approach is possible with improved bonding methods and fluoride-releasing materials. The cariostatic potential of fluoride-releasing cements has been validated through clinical experience and laboratory research.^4-7 Improvements in the physical properties of glass-ionomer and resin-ionomer materials permit conservative, minimally invasive restoration of caries and functionally acquired defects in the teeth. The adhesive properties of these materials allow retention of ionomer restorations with very little or no tooth preparation.^8,9 This conservative approach is provided to prevent a positive advancement compared to the relatively aggressive tooth preparation that was required to mechanically retain most restorative materials two decades ago.

The operative concept of "extension for prevention" has given way to treatment plans oriented to "prevent the extension" by eliminating the need for many invasive restorative procedures. For example, the effectiveness of occlusal sealants in preventing caries is well-documented in the dental literature.^10-12 This ultraconservative therapy is provided in advance of the appearance of disease as a preventive measure.

A better understanding of the biocompatability of dental materials has dramatically improved the strength of dentin bonding procedures. For example, it is well-documented that acid contact with dentin does not result in pulpal death as was universally thought 20 years ago.^13,14 This discovery coupled with research into the ultrastructure of dentin has led to successful techniques for bonding resin materials to dentin as well as enamel. This has had a powerful impact on the development of esthetic dentistry and expansion of the menu of treatment modalities available to the patient.

Recognition that eugenol inhibits polymerization of dental resins has led to a sharp decline in the use of eugenol-containing medicaments and restorative materials.^15,16 Dental science has shown that the health of the dental pulp depends more upon disinfection and isolation than upon medication.^17-19 A better understanding of pulp biology and an awareness materials biocompatibility have resulted in more-predictable procedures when developing a treatment plan.

Twenty years ago, all-porcelain crowns were rarely used due to difficulties in achieving a precision fit, their capacity to abrade opposing teeth, and the high frequency of fracture. Porcelain-fused-to-metal crowns predominated because of their improved durability and reasonable esthetics. Unfortunately, the potential of the PFM crown to mimic the appearance of natural teeth is limited by the presence of opaque porcelains that hide the metal and reflect light differently than natural teeth. The durable bond of composite resin to etched porcelain coupled with new high-strength, lower-fusing porcelains has opened new doors of opportunity for fabrication and placement of thinner, stronger, more natural looking all-porcelain crowns and veneers that are less abrasive to opposing dentition. Conservative removal of only the enamel or superficial dentin permits maximum conservation of healthy tooth structure and preservation of the health of the dental pulp.

Prosthodontics and Treatment Planning

Treatment planning in prosthodontics has changed dramatically in the past decade because of the acceptance of dental implants as a viable long-term option to replace missing teeth. Although various types of dental implants have been used for centuries, it is only in the past couple of decades that predictable results have been achieved in both partially and completely edentulous patients. With the increase in the predictability of implants come treatment planning questions as to when to use conventional prosthodontic procedures and when to consider implant prosthodontics. The purpose of this review is to outline how the implant option has influenced clinical decision making in prosthodontics.

Prosthodontic treatment planning has changed because it is no longer appropriate to consider high-risk procedures when a more predictable alternative such as an implant is available. Higher risk endodontic or periodontal procedures to save teeth for prosthodontic abutments are of questionable value because of the predictable alternative of dental implants. For example, procedures such as root amputations or hemisections, which have a five-year failure rate of between 30 percent and 50 percent, are less frequently considered now that implants are available.^20-22 Treatment that includes long-span fixed partial dentures or multiple splinted teeth should be carefully compared to the implant alternative. Additionally, endodontic procedures such as an apicoectomy or retrofills should be considered carefully not only because of the limited benefit, but also because of the possibility of compromising a potential implant site. Periodontal procedures such as crown lengthening should also be considered in that a reduced bone volume may compromise both the hard and soft tissue for a future implant site.

A commonly encountered clinical situation that requires a prosthodontic treatment planning decision is when a patient presents with a broken down molar that will require extensive therapy to restore. Restoration of the tooth may require a root canal, crown lengthening, a build-up restoration, and placement of a crown. The alternative would be to extract the tooth and place a single-tooth implant. The question becomes a comparison of the cost, time, and efficacy of restoring the tooth or placing an implant.

When comparing the relative merits of restoring a broken down tooth versus extracting the tooth and placing an implant, both the surgical and restorative success rates over various periods need to be compared. Unfortunately, current literature evaluating the success rates of root canal therapy on molars is lacking. Older literature has shown a five-year success rate of root canal therapy to be between 90 percent and 92 percent for vital teeth and slightly less for nonvital teeth.^23,24 This can be compared with the five-year osseointegration success rate with an implant, which ranges from 93 percent to 98 percent.^25,26 The complication rate of a crown on a tooth is lower than a crown on an implant; ²⁷ however, in many situations a single-tooth implant will be the treatment of choice.

A second clinical situation that requires a prosthodontic treatment planning decision is when a patient is missing a tooth and the restorative dentist needs to consider a FPD or single-tooth implant. A FPD to replace a missing tooth has several advantages, including high patient acceptance, relatively favorable insurance coverage, a comparatively short treatment time, and experienced laboratory support. In addition, the dentist has had previous formal training in FPD procedures.

Fixed partial dentures have been shown to be a very satisfactory solution to replace a missing tooth. A recent review of fixed partial denture survival by Scurria and colleagues showed an 87 percent 10-year survival rate and a 69 percent 15-year survival rate.²⁸ The abutment tooth survival rate at 10 years was estimated to be 96 percent, but drops off rapidly after that.²⁸ The primary cause of failure was a loose retainer, and the second most common cause was recurrent caries. Bragger and colleagues compared the frequency of biologic and technical complications in 85 patients with FPDs on natural teeth over a five-year period and found biologic complications to be caries (2.8 percent), endodontic problems (4.9 percent), and periodontal problems (4.1 percent).²⁹ The most common technical complication was porcelain fracture, which occurred in 6.1 percent of patients.²⁹ Important factors to consider before treatment planning for a fixed partial denture would be the condition of the proximal teeth, the potential for the loosening of abutments, and the patient’s ability to avoid caries or periodontal problems through adequate oral hygiene. A patient at high risk for complications with a fixed partial denture should be considered for a single-tooth implant.

The traditional disadvantages of treatment planning with dental implants are of decreasing significance. For example, implants can be completed in a one-stage procedure more predictably, thereby avoiding a second surgery. Additionally, improvements in the implant surface result in faster osseointegration and decreased treatment time. Limited bone availability is less of a factor now that there are better grafting materials and techniques for site preparation that can include orthodontic extrusion, distraction osteogenesis, or onlay grafting.

Periodontal Assessment and Treatment Planning

The goal of this brief outline is to focus on areas of periodontal treatment planning that have changed in the last decade. Risk assessment, tissue preservation, and tissue reconstruction will be reviewed with the goal of integrating these concepts to develop a coherent periodontal treatment plan.

Local and Systemic Risk Assessment

The goals of periodontics have been to halt attachment loss due to disease, regenerate attachment when possible, and provide stable elements for the restorative dentist by assessing the risk of failure in restoratively critical teeth. With the increasing use of implants to replace missing teeth, reliance on the periodontist to provide stable abutments and retainers has decreased. Missing teeth are now more appropriately replaced with implants rather than fixed partial dentures, and implants are also used to support removable partial dentures, making the restorative dentist less reliant on the periodontal prognosis of questionable teeth.³⁰

The periodontally compromised tooth can now generally be considered in isolation, no longer serving the crucial role of supporting its missing neighbors. Now it is not prudent to maintain endodontically and periodontally compromised teeth when they can be replaced with implants, and the timing of extraction must be considered differently if implants are to be considered. In addition, esthetics play a greater role in decisions regarding compromised teeth. Both of these issues will be explored in a later section on tissue preservation.

Furcation involvement remains the most important single tooth risk factor in predicting the outcome of treatments. ³¹ During the past decade, the concept of tissue regeneration has been put into everyday practice and its promises and limitation explored.³² While guided tissue regeneration has been successful for some furcation involvements, others have not responded well to this therapy.³³ Initially, it was used in nearly every possible situation, but an appreciation of the limitations of this technique has forced clinicians to be more selective.

The 1996 World Workshop in Periodontics listed three bacteria as risk factors for periodontal disease.³⁴ Despite this finding, treatment planning has not changed. Few practitioners are willing to culture the oral flora and identify targeted organisms when developing their treatment plan. This is unfortunate since certain periodontal diseases have unique manifestations due to their microflora. Therapy based on targeting specific bacteria may be more successful and potentially result in less surgery. These changes, albeit small, have set the stage for consideration of virulence in the bacterial population, and the sequence of the genomes of these organisms will likely result in further changes in treatment planning.

If furcation involvement is the most important single tooth factor in periodontal risk assessment, then smoking has become the most important overall risk factor. ^35,36 Recent information about the effects of smoking on periodontal health has come to light; and, with its effect on implant survival and guided tissue and bone regeneration success, this behavior becomes paramount in predicting the outcome of disease in periodontal patients.^36,37

Another important factor that has surfaced in the past decade is the certainty that genetic makeup is critical in determining periodontal disease patterns in the population. An important piece of evidence is the identification of genetic markers for the host response that can now be categorized as risk factors.³⁸ While the single marketed product (PST) still remains controversial,³⁹ there is little doubt that this test and others like it will form critical aspects of treatment planning and prognostication in the future.

Another change in treatment considerations in periodontal therapy that has occurred in the past decade is greater inclusion of systemic diseases in considering the outcome of disease in individuals with these conditions.⁴⁰ Diabetes has been known to cause a greater expression of the periodontal disease process for more than the past 10 years; however, greater understanding of this disease and how periodontitis is influenced by it allows for some modification in treatment planning for diabetic patients. It has also been confirmed that periodontal disease may affect the expression of diabetes;⁴¹ and, with this concept in mind, the effect of periodontal disease on other systemic illnesses has been explored in the past decade.⁴² Heart disease, pregnancy, and respiratory disease have been implicated as having an effect on periodontitis. These associations have not affected periodontal treatment planning per se, but may contribute to more patients being treated for periodontal disease than before.

Other systemic conditions that are now being considered as periodontal risk indicators are osteoporosis and estrogen deficiency, and these do tend to alter the way periodontal disease is treated.⁴³

Tissue Preservation

Tissue preservation has become a unifying concept in periodontal treatment planning. Previously, an assessment may have focused on whether a tooth would be a reliable or unreliable prosthetic abutment. With dental implants now a treatment option, the clinician must decide whether retaining a periodontally questionable tooth will result in more alveolar bone loss. This may limit or eliminate the future use of a dental implant. The concept of strategic extraction to preserve adequate tissue for dental implants is a key determinant for treatment planning. This approach is highly influenced by clinicians’ ability to preserve and regenerate soft and hard tissue in preparation for dental implants.

Tooth removal must be carefully planned to preserve as much of the soft and hard tissues as possible not only to create the best esthetic result, but also to ensure the most functional and long-lasting results. It is now uncommon to remove an anterior tooth without considering preserving the ridge regardless of whether the missing tooth will be restored by a fixed partial denture or an implant.

A number of recent technologies and practices come into play in the implementation of these therapies. Guided bone regeneration, the use of membranes, and plasma-derived growth factors are the most common strategies employed. As these and other products of the biotechnology revolution continue to be introduced, clinicians’ ability to preserve and reconstruct the periodontium and alveolus will improve.

Tissue Reconstruction

Esthetics and function also drive the reconstruction side of periodontal treatment planning. The two focal points of reconstruction are the root surface and the alveolar process. In the past decade, the regenerative capabilities of the periodontium have been researched and are being used in practice. Biomimetics, genomics, and bioengineering have made some changes in the way we approach the treatment planning of periodontitis.

In many cases, the root surface ligamentous attachment can now be predictably rebuilt after being lost due to periodontal disease or trauma. However, this therapy may possibly have been exhausted in the last decade. Although there continue to be indications for its use,⁴⁴ as its limitations have been exposed, it is no longer as widely employed as it was in the 1990s. Many of the products that were developed for use with this treatment, however, have ended up being used in the practice of guided bone regeneration and root coverage.

Root coverage techniques have become remarkably predictable, and their use has therefore become more widespread. There is still some controversy regarding the minimal amount of gingiva necessary to prevent recession; but, given the opportunity to rebuild lost tissue, most dentists and patients will choose these techniques.⁴⁵

The need for a complete alveolar process unites esthetics and function again. When maxillary anterior teeth are lost, it is imperative that tissue preservation techniques are used to retain as much of the normal architecture as possible, and when this preservation fails or is neglected (see article this issue), reconstructive techniques must be used.

Surgeons in the treatment planning process now occupy a new role; they must assess the ability of the remaining ridge to accept a dental implant or implants and provide or reconstruct a ridge that will accept implantation. All types of bone grafting strategies are now being used, which will prompt future advances in bioengineering and biological response modifiers. Autogenous and allogenic onlay grafts and a variety of sinus floor alterations along with membranes and growth factors are currently being used, and these strategies will soon become universal.

The biotechnology industry has always been an integral part of the dental marketplace. However, with the explosion of information, there is a lot more to consider in any one treatment approach. There will continue to be a myriad of diagnostic tests. The opportunity for companies to sell products designed to regenerate bone and attachment has greatly increased. Some of these offerings seem nearly magical in nature, and others are akin to snake oil. It is a constant struggle for the clinician to separate the wheat from the chaff when it comes to these products and services.

In conclusion, some of the vital things that have not changed in periodontics are identification of specific periodontal pathogens, effective management of furcation involvements, and proper diagnosis of disease activity or attachment loss. These factors profoundly affect the clinician’s ability to accurately assess the prognosis of individual teeth. What has changed is an improved understanding about smoking, genetic predisposition, estrogen deficiency, osteoporosis, and diabetes, and the relationship of these systemic conditions to periodontal health. Esthetics and ridge preservation must also be considered more than ever before. But the most important change in periodontal treatment planning is the strategy that the patient’s needs can best be served by the judicious removal of periodontally compromised teeth and replacement with dental implants.

Orthodontics and Treatment Planning

The past two decades have brought significant changes to the practice of orthodontics. Treatment is no longer reserved only for the juvenile and adolescent age groups. The advent of more esthetic and socially acceptable brackets, advancements in wire technology resulting in longer appointment intervals, and better insurance coverage for orthodontic services have significantly broadened the age spectrum as well as the scope of orthodontic treatment. On one end of this spectrum, orthodontic treatment is beginning at a much younger age than ever before; on the other end, adults and even the elderly are seeking orthodontic treatment as a critical part of the solution to their overall oral rehabilitation.

There is now greater emphasis on proper timing for early orthodontic intervention. Most orthodontic referrals used to be made when all the primary teeth had exfoliated. Children were generally seen for their first orthodontic examination around age 12 or 13. Consequently, there was little opportunity for any growth modification, habit elimination, or arch development; and crowding in most cases was resolved by extraction of teeth. Many warning signs of developing malocclusions appear in the early mixed dentition. This recognition has resulted in much earlier screenings. Ideally, children should be screened for orthodontic treatment no later than age 7, when the six-year molars and most of the upper and lower incisors have erupted. This allows the orthodontist to assess the anteroposterior, transverse, vertical, and functional relationships of the jaws. In addition, arch length discrepancies and habit patterns can be evaluated. Referral for an orthodontic screening at age 7 does not always result in immediate treatment but allows the orthodontist to determine how and when the child’s particular problem should be treated for maximum improvement with the least amount of time and expense. Although growth-related and skeletal problems must be addressed early for maximum benefit, many orthodontic problems can wait for treatment until appearance of the late mixed dentition or permanent dentition.

There has been a major paradigm shift in orthodontic diagnosis and treatment planning. The goal of the orthodontist is no longer just to fit the teeth within the dental arches at all cost. Contemporary orthodontists now strive to attain facial esthetics, dental esthetics, periodontal health, optimum functional occlusion, temporomandibular joint health, and long-term stability. Proper tooth positioning is now more than ever before dictated by what the face and the periodontium allow. Therefore "extraction" and "non-extraction" are no longer considered treatment goals but are merely treatment plans intended to place the teeth in a periodontally stable position within a well-balanced face.

Furthermore, what was considered a beautiful face in the 1960s differs significantly from what is considered beautiful today. A simple comparison of today’s fashion magazines with those of 40 years ago clearly indicates that facial esthetic criteria have been redefined in response to ethnic and cultural diversity. Many of the commonly used cephalometric norms that were obtained based on North American Caucasian subjects render themselves useless in planning treatment for today’s diverse and heterogeneous patient population. There is also raised awareness of the importance of soft tissue response to orthodontic treatment and orthognathic surgery. Many of the more contemporary cephalometric analyses have been designed based on soft-tissue objectives and how skeletal and/or dental movements affect the soft tissue.

Advances in digital imaging and radiography have significantly facilitated diagnosis and treatment planning. Many orthodontic software programs have been developed to aid orthodontists in simulating various treatment possibilities, allowing them to better educate their patients about expected results and provide proper informed consent. These simulations, referred to as visualized treatment objectives, which were quite tedious to do before computerization, test the feasibility of various treatment plans and the effect of the proposed treatments on appearance. This can be particularly powerful when surgical and nonsurgical options are being compared.

With more adults seeking orthodontic treatment than ever before, orthodontists find themselves instrumental members of a multidisciplinary team. Adult treatment can pose several challenges. Many adults seeking orthodontic treatment present with several dental problems including abraded or worn teeth; peg-shaped or atypical teeth; old, failing restorations; multiple edentulous spaces; tipped teeth; congenitally missing permanent teeth and over-retained deciduous teeth; recession and periodontal breakdown; and temporomandibular disorder. Coordination and proper sequencing of treatment with other specialists is essential for a successful treatment result. Implants have not only become a viable restorative option to replace missing teeth, but have also opened up many orthodontic possibilities. Implants have proven to be an excellent means of providing anchorage in the edentulous spaces to make tooth movement possible elsewhere within the arch.

Despite inconsistent and questionable literature on the correlation between occlusion and TMD, condylar stability prior to initiation of orthodontic treatment is considered an important prerequisite for proper diagnosis and treatment planning. For the dentist to avoid surprises, TMD must be controlled prior to starting orthodontic treatment. A mutually protective occlusion with centric occlusion and centric relation as coincident as possible has become an ideal goal.

Although insurance coverage for orthognathic surgery continues to pose a challenge, more adults are considering surgery to correct skeletal malocclusions. The use of rigid fixation in lieu of intermaxillary wire fixation has significantly improved postoperative comfort and long-term stability. Furthermore, recent refinements in distraction osteogenesis have made possible the correction of extremely severe skeletal malocclusions that would have failed in response to conventional surgical orthodontics.

The addition of transparent aligners to the orthodontist’s armamentarium has opened up many possibilities for adult treatment. For adults who have always wanted straight teeth but have been resistant to braces, this has been a dream come true. These transparent aligners have been effective in correcting mild to moderate crowding and spacing problems in permanent dentition. Aligners are also being used in combination with braces to correct more-difficult cases while minimizing time in fixed appliances. Proper case selection is critical for a successful result. Although this new technology still has several limitations, it is showing great promise and is being explored further.

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To request a printed copy of this article, please contact/Donald A. Curtis, DMD, UCSF School of Dentistry, 707 Parnassus Ave., San Francisco, CA 94143-0758.