The importance of incisor positioning in the esthetic smile: the smile arc.

The smile arc is defined as the relationship of the curvature of the incisal edges of the maxillary incisors and canines to the curvature of the lower lip in the posed smile. The ideal smile arc has the maxillary incisal edge curvature parallel to the curvature of the lower lip. Evaluation of anterior smile esthetics must include both static and dynamic evaluations of profile, frontal, and 45 degrees views to optimize both dental and facial appearance in orthodontic planning and treatment. This article presents the concept of the smile arc and how it relates to orthodontics-from the recognition of its importance, to its impact on orthodontic treatment planning, to how procedures and mechanics are adapted to optimize the appearance of the smile. Three cases are used to illustrate how treatment is directed, emphasizing how facial and smile goal setting go hand in hand.

The emerging soft tissue paradigm in orthodontic diagnosis and treatment planning.

Until now, orthodontic diagnosis and treatment planning has been based on hard tissue relationships and on the Angle paradigm that considers ideal dental occlusion 'nature's intended ideal form'. In this view, the clinician and nature are partners in seeking the ideal. In the modern biological model, variation is accepted as the natural form; ideal occlusion is the exception rather than the rule, and the orthodontist and nature are often adversaries. The orthodontist's task is to achieve the occlusal and facial outcomes that would most benefit that individual patient, whose esthetic concerns are often paramount. Because the soft tissues largely determine the limitations of orthodontic treatment, from the perspectives of function and stability, as well as esthetics, the orthodontist must plan treatment within the patient's limits of soft tissue adaptation and soft tissue contours. This emerging soft tissue paradigm in diagnosis and treatment planning places greater emphasis on clinical examination of soft tissue function and esthetics than has previously been the case, and new information in these areas is required.

How to avoid surgical failures.

Problems and failures in orthodontic-orthognathic surgical treatment are frequently discussed among colleagues, but not often written about. This lack of documentation may be attributed to a natural inclination for us to report our successes and hide our failures. More positively, we believe the lack of written material on complications probably relates more to the overwhelming success rate in these procedures than to an inclination to hide failures. In addition, some complications are clearly a result of the orthodontic care before and/or after the surgical procedure. This article concentrates on exploring the many complications in orthognathic surgery that are more a result of the orthodontic phase of care, and how the orthodontist can react to and manage surgical complications to achieve a successful result. The more the orthodontist understands the nature of surgical problems, the more able he/she is to manage them.

Evaluation of video imaging prediction in combined maxillary and mandibular orthognathic surgery.

The purpose of this study was to evaluate the accuracy of the soft tissue profile "line drawings" predicted by Quick Ceph Image in combined maxillary and mandibular orthognathic surgical procedures. Preoperative (mean = 27.7 days presurgical) and posttreatment (mean = 11.5 months postsurgical) lateral cephalograms of 40 white patients (10 males and 30 females) who had completed treatment that involved orthodontics, one-piece LeFort I osteotomy, and mandibular advancement by bilateral sagittal split osteotomy with or without genioplasty were used in the study. Forty-five lateral hard and soft tissue landmarks were digitized, using the "on-screen" digitizing option, for each cephalogram and for each computer predicted posttreatment tracing. A customized analysis consisting of 24 linear and 4 angular measurements was used to analyze the differences between the actual posttreatment cephalometric landmark measurements and computer predicted landmark measurements. Statistically significant differences between the posttreatment cephalometric soft tissue profiles and the computer predicted soft tissue profiles were analyzed for the total sample, patients grouped according to: magnitude and direction of maxillary movements, adjunctive genioplasty procedure, V-Y closure of the LeFort I incision, and gender and age differences. The results indicated that for some of the soft tissue landmarks, differences were found between the posttreatment and the computer predicted profiles. Differences between the predicted and actual posttreatment soft tissue profiles may be attributed to the inaccuracy of Quick Ceph Image's default soft to hard tissue ratios when predicting the soft tissue response to combined maxillary and mandibular orthognathic surgical procedures.

Combined rapid maxillary expansion and protraction facemask in the treatment of Class III malocclusions in growing children: a prospective long-term study.

A prospective study of 28 growing children (mean age of 8 years 3 months) with Class III malocclusions was consecutively treated using rapid maxillary expansion and maxillary protraction. All patients were treated from a negative overjet to a positive overjet and from a Class III dental malocclusion to a Class I dental relationship. For each patient, a lateral cephalogram was taken before treatment (T1), immediately posttreatment (T2), and after an observation period (T3) averaging 2 years 5 months. Using analysis of variance, the cephalograms were analyzed to determine skeletal and dental changes resulting from treatment. Long-term changes (2 years 5 month observation period) were also evaluated. Results showed that immediately posttreatment, the maxilla moved anteriorly a mean of 1.54 mm and Sella-Nasion-A point increased 0.87 degree. The maxillary teeth moved anteriorly 2.73 mm and proclined 5.23 degrees, while the mandible rotated in a downward and backward direction. Long-term, the anterior position of the maxilla was maintained, but some of the Class III correction was lost because of mandibular growth. Comparison of this study's results to Riolo's longitudinal Class I data showed that, overall, rapid palatal expansion and maxillary protraction produced a small orthopedic effect with a moderate dentoalveolar effect which together contributed to the correction of the Class III malocclusion.

Nonsurgical treatment of open bite in nongrowing patients.

Successful treatment of the adult patient with an open bite dental or skeletal pattern often presents a difficult challenge. While the causes of open bite may be multifactorial in nature, there are specific diagnostic criteria that may allow for an orthodontic treatment modality incorporating extraction therapy with retraction of incisors. Two case presentations illustrate treatment of adult patients with open bites due to proclined incisors. The diagnostic criteria and mechanics for appropriate and successful treatment are discussed. Although the selection of extraction therapy for correction of anterior open bite has a narrow range of application in the overall scheme of open bite treatment, this treatment method has certain areas of application in which success may be anticipated.

The accuracy of video imaging in orthognathic surgery.

Video imaging is an important emerging technology in planning orthognathic surgery and educating patients about the esthetic effects of treatment. The presurgical cephalograms of 56 patients, 41 with mandibular advancement alone and 15 with mandibular advancement plus genioplasty, were digitized, and the computer-generated soft tissue "line drawing" predictions were compared with the actual posttreatment cephalograms. Video images of the patients' presurgical lateral view were obtained, and two experienced clinicians compared the computer generated video image predictions with the actual posttreatment profile. Video images judged very good or excellent were considered acceptable for treatment planning; 60% to 83% met this criterion, depending on the profile area viewed. The percentage of acceptable images in the lower lip, labiomental fold, and chin area decreased with the addition of a genioplasty. The predicted and actual posttreatment soft tissue line drawings were quite similar for all areas except for the lower lip region, where statistically significant differences were noted, with the predicted lower lip more retrusive and thinner than the actual contours. For the lower lip and chin, a 2 mm or more discrepancy was observed in 20% of the patients. In all cases, the actual image was judged more esthetic than the predicted image, allaying fears of unrealistically optimistic computer generated predictions.

The quantification of soft tissue cervicomental changes after mandibular advancement surgery.

Surgical mandibular advancement results in many soft tissue changes. The purpose of this study was to quantify the changes seen in the cervicomental angle and the lip-chin-throat angles in response to mandibular advancement, as well as hyoid bone positional changes. As a result of statistical analysis of hyoid bone and soft tissue linear and angular changes, prediction models are presented as to the soft tissue response to mandibular advancement in the cervicomental region.

The esthetic impact of orthodontics: planning treatment to meet patients' needs.

Successful orthodontic therapy in the growing patient involves the coordination of mechanotherapy, growth modification techniques, knowledge of hard and soft tissue growth patterns and patient motivational techniques. These cases represent differing types of Class II malocclusions in which the causes and treatment solutions were quite varied. The differing esthetic needs used treatment plans designed after a careful, problem-oriented assessment of the patient's needs. In each case, the success involved appropriate timing, differential diagnosis, excellent patient cooperation and the design of treatment plans to satisfy occlusal and esthetic goals. Teamwork between general practitioners and orthodontists is critical in meeting patients' needs.

Video imaging--a computer facilitated approach to communication and planning in orthognathic surgery.

A case report is presented in order to illustrate the benefits of computerized video imaging in orthognathic surgery. It is suggested that superimposition of the cephalogram on the video image is helpful in treatment planning and in communication with the patient. Computerized video imaging techniques help clinicians and patients discuss the aesthetic impact of orthognathic surgery. The superimposition of the cephalogram and profile image, coupled with algorithmic predictions, allow the clinician to plan the surgery to closely match the desired result. This paper presents the planning and counselling of a patient using contemporary computerized video imaging techniques.

Orthognathic surgery and aesthetics: planning treatment to achieve functional and aesthetic goals.

Computerized video imaging is a valuable adjunct for communication with patients and planning orthognathic surgical treatment. The incorporation of adjunctive soft tissue procedures to enhance the final aesthetic result of orthognathic surgery is a valuable addition to the orthodontic and orthognathic treatment plan. This paper presents the use of video imaging techniques in the planning and execution of comprehensive functional and aesthetically orientated orthodontic and surgical treatment.

Diagnosis and treatment planning of hypodivergent skeletal pattern with clockwise occlusal plane rotation.

Diagnostic treatment planning of Class III malocclusion is complicated due to the interaction of development, timing, dental pattern, and skeletal relationships. Historically, the treatment of adult Class III malocclusions has tended to be seen primarily as cases of mandibular prognathism. As diagnostic acumen and surgical skills improve and merge, orthodontic and surgical treatment plans for Class III malocclusions have become more common. Class III malocclusions now tend to be described in terms of mandibular prognathism, horizontal maxillary hypoplasia, maxillary vertical hypoplasia, and mandibular dentoalveolar retrusion. The purpose of this paper is to present a combined surgical-orthodontic treatment approach involving clockwise rotation of the occlusal plane for treatment of hypodivergent Class III skeletal pattern and dental malocclusion.

Videoimaging: the pros and cons.

I have tried to make some thoughtful points based on a fair amount of experience in the use of videoimaging, both in research and clinical application. The technical development of computerized videoimaging has progressed greatly in the past several years, in response to the profession's interest in it. While many orthodontists have become interested in this technology because of its potential in communication and marketing, I feel its greatest potential lies in the area of diagnosis and treatment planning. The use of integrated and facial images has allowed me to visualize the face (primarily in profile, although the frontal view can be useful when evaluated and manipulated properly) and recognize particular aspects and patterns of treatment options I had not recognized before (Figures 4-6). Obviously, a great deal of research must be done in the future before we can completely integrate this technology into our treatment of patients. These studies are just beginning. I feel confident that computerized videoimaging will help expand our vision as we strive to deliver the best care possible; nevertheless, we must evaluate this technology rationally and define its strengths and weaknesses just as clearly as we have for our cephalometric tools.

Incorporation of facial plastic surgery in the planning and treatment of orthognathic surgical cases.

Until recently, orthognathic surgery and cosmetic soft tissue surgery have been separate clinical endeavors. This article presents examples of soft tissue surgical procedures carried out with orthognathic surgery to enhance the overall result. Video imaging techniques have been integrated into the planning process to more clearly define functional and esthetic goals. The technical achievement of combined orthognathic and esthetic procedures, as well as the timing of treatment between the orthodontist, oral surgeon, and plastic surgeon, is discussed.