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The impact of orthognathic surgery on the pharyngeal airway supported by cone-beam computed tomography (CBCT) technology has been the topic of many recent studies. The minimum cross-sectional area (MCA) has also been evaluated but not with respect to vertical position changes of the MCA with movement of the facial skeleton. Vertical position changes and shape changes of 71 patients after orthognathic treatment of Class II and Class III malocclusions were evaluated with CBCT images and Invivo5 software. The vertical changes were found not to be significant for Class II and Class III patients (5.0mm and 0.2mm respectively, p = 0.31). In addition, the vertical changes of the MCA with individual skeletal movement were also not significant. The shape changes were not consistent relative to individual Angle classification. Vertical changes of the MCA after orthognathic surgery could not be associated with Angle's classification or skeletal movement while shape changes were not predictable. Orthognathic surgical planning is a complex process in which the patient's occlusion, facial balance, and harmony are considered. The purpose of this article is to provide surgical insight into obtaining the best possible results when considering the multifactorial nature of orthognathic surgical treatment planning. Original research on the changes in MCA will be presented.

Orthognathic surgery has seen many developments and advances throughout its evolutionary history. Recent trends have seen a shift away from traditional model surgery and have sought to embrace more contemporary methods of virtual surgical planning (VSP) [1]. Since its inception, orthognathic surgery has successfully and predictably been planned and performed by means of traditional, analytical model surgery. Introduction of the cone-beam CT in 1998 in Europe and then in the USA in 2001 provoked the beginnings of a paradigm shift [2, 3]. The literature has since been replete with studies focused on providing evidence that virtual surgical planning is as effective and predictable as traditional model surgery [4–6].

Orthognathic surgery is one of the most important treatment options available to an orthodontist, especially in cases of significant skeletal malocclusions. In order to accurately measure any changes that may have occurred following orthognathic surgery, data regarding shape changes occurring in the temporomandibular joint is necessary. CBCT imaging can provide more complete three-dimensional information related to these changes than has been possible in the past. The use of three-dimensional CBCT data has allowed for a more complete analysis of changes that have taken place in the TMJ with orthognathic surgery, with changes primarily taking place bilaterally in posterior, superior, and lateral aspects of the condylar heads and posterior regions of the fossae.

Introduction Findings from early cephalometric studies on airway changes after 2-jaw orthognathic surgery have been challenged because the previous anteroposterior interpretation of airway changes can now be evaluated in 3 dimensions. The aims of this study were to use cone-beam computed tomography to quantify the nasopharynx, oropharynx, and total airway volume changes associated with skeletal movements of the maxilla and mandible in a sample of patients undergoing 2-jaw orthognathic surgery for correction of skeletal malocclusion. Methods Skeletal movements and airway volumes of 71 postpubertal patients (31 male, 40 female; mean age, 18.8 years) were measured. They were divided into 2 groups based on ANB angle, overjet, and occlusion (Class II: ANB, >2°; overjet, >1 mm; total, 35 subjects; and Class III: ANB, Results Horizontal movements of D-point were significantly associated with increases in both total airway (403.6 ± 138.6 mm 3 ; P 3 ; P 3 ; P = 0.04) and oropharynx volume (−639.7 ± 195.3 mm 3 ; P 3 ; P 2 ; P 3 ; P = 0.02) and oropharynx (−648.2 ± 270.4 mm 3 ; P = 0.02) volumes. A similar negative association was observed for the most constricted area for the vertical movement of D-point (−15.45 ± 4.91 mm 2 ; P Conclusions Optimal control of airway volume is through management of the mandible in the horizontal direction and the vertical movement of the posterior maxilla for all patients. The surgeon and the orthodontist should optimally plan these movements to control gains or losses in airway volume as a result of orthognathic surgery.

Make your collections memorable and accessible to audiences of all abilities by incorporating the principles of universal design (UD) in your museum exhibits. Universal design provides equitable access to resources, much the way that curb cuts improve access to roads and sidewalks. Museums spend considerable effort protecting specimens from agents of deterioration but this usually means that only one sense - vision - is employed in our exhibits. Providing greater accessibility may seem daunting, expensive, or dangerous for specimens but, by considering a few principles during exhibit development, UD is readily implemented and can make displays more effective than ever for people of all abilities, levels of understanding, and backgrounds. This is because UD goes beyond simple accessibility, it generates innovative solutions through the creative application of seven basic principles: equitable use, flexibility in use, simple and intuitive use, perceptible information, tolerance for error, low physical effort, and effective size and space for approach and use. We will discuss how the principles of UD are fundamental to good exhibit design and can be especially effective in a natural history setting - both in the gallery as well as the classroom - because we can use authentic objects that are largely identical to the display specimens. Such authentic and multisensory products encourage empathy and biophilia, increase specimen and visitor safety, and improve overall quality of service. We will also show how our institution has incorporated students into the process of design, evaluation, and construction of UD exhibits as a way to both include diverse perspectives in the design process and as a way to train science communicators of all kinds.

Do you know what a kiwi looks like - all the way down to the orientation of the nostrils? While small details won’t make or break the aesthetics of an exhibit, they can have important impacts on visitor learning and future behavior. Museums are a traditional bastion of authenticity. From the objects we exhibit to the information we share, audiences know that museums are a trustworthy source of real objects and vetted facts. We strive to ensure accurate label copy, but the traditional constraints of preservation and exhibition of natural history specimens can still convey confusing or implicitly inaccurate information. Problems like sub-standard taxidermy, faded mounts, heedless application of plants, and inaccurate social groupings abound in museums. Visitors are usually not equipped to evaluate such details, yet such details often become a baseline from which visitor’s expectations of nature are derived. Therefore, accurate representations of species are an important way to convey both explicit institutional messages and implicit information about nature. We will discuss the fundamental details that differentiate award-winning taxidermy from substandard representations of the species. We will show how to employ a few, fundamental principles to overcome the constraints of preservation to make mounts, dioramas, and artificial reproductions as exciting, beautiful, and accurate as possible.

Introduction: Maxillary surgery on a bone segment enables movement in the sagittal and vertical planes. When performed on multiple segments, it further provides movement in the transverse plane. Typical sites for interdental osteotomies are between laterals and canines, premolars and canines, or between incisors. Additionally, osteotomies can be bilateral, unilateral or asymmetric. The ability to control intercanine width, buccolingual angulation of incisors, and correct Bolton discrepancy are some of the advantages of maxillary segmentation between laterals and canines. Objective: This article describes important features to be considered in making a clinical decision to segment the maxilla between laterals and canines when treating a dentoskeletal deformity. It further discusses the history of this surgical approach, the indications for its clinical use, the technique used to implement it, as well as its advantages, disadvantages, complications and stability. It is therefore hoped that this paper will contribute to disseminate information on this topic, which will inform the decision-making process of those professionals who wish to make use of this procedure in their clinical practice. Conclusions: Segmental maxillary osteotomy between laterals and canines is a versatile technique with several indications. Furthermore, it offers a host of advantages compared with single-piece osteotomy, or between canines and premolars. Introdução: a cirurgia de maxila em um segmento ósseo possibilita sua movimentação nos planos sagital e vertical. Quando realizada em múltiplos segmentos, contempla também o plano transversal. A localização das osteotomias interdentárias pode ser: entre incisivos laterais e caninos, entre pré-molares e caninos, ou entre os incisivos centrais - podendo ser bilateral, unilateral ou assimétrica. A possibilidade de controle da distância intercaninos, da angulação vestibulolingual dos incisivos e da correção da discrepância de Bolton é uma das vantagens da segmentação da maxila entre incisivos laterais e caninos. Objetivo: o presente artigo descreve aspectos importantes, no tratamento das deformidades dentoesqueletais, a serem considerados na decisão clínica de segmentar-se a maxila entre os incisivos laterais e os caninos. Serão discutidas, também, a história dessa abordagem cirúrgica, as indicações para seu emprego clínico, a técnica para sua utilização, bem como suas vantagens, desvantagens, complicações e estabilidade. Desse modo, espera-se contribuir para o aumento das informações disponíveis sobre o assunto, subsidiando a decisão dos profissionais que queiram considerar o uso dessa técnica em suas atividades clínicas. Conclusão: a osteotomia segmentar de maxila entre os incisivos laterais e os caninos corresponde a uma técnica versátil com diversos tipos de indicações, e apresenta uma série de vantagens, quando comparada com as osteotomias em um segmento ou entre caninos e pré-molares.

Purpose: The purpose of this study was to evaluate the effectiveness of a resorbable plating system (Lactosorb; Walter Lorenz Surgical, Inc, Jacksonville, FL) as a fixation method in the treatment of craniosynostosis. Patients and Methods: Ten children with 15 affected sutures underwent craniotomies ranging from release of 1 suture to total calvarial reconstruction. The 1.5 Lactosorb plating system was used as the method of fixation in all cases. Patients were evaluated clinically and with computed tomography scans before discharge postoperatively, and at the 3-, 6-, and 9-month intervals. Results: In all 10 cases there was no evidence of neosynostosis, malposed osseous segments, or restriction of growth or calvarial expansion. In addition, none of the complications seen with more traditional techniques were evident in these patients. Conclusion: Resorbable plating systems provide a viable alternative to the more traditional fixation techniques that have been used to treat craniosynostosis and craniofacial dysostosis. © 2001 American Association of Oral and Maxillofacial Surgeons

Objective. The purpose of this study was to record the generation of heat in selected titanium implants while exposing them to a superpulsed CO2 laser mode. These results can be compared with previous studies in which continuous and pulsed CO2 laser modes were used. Study Design. Titanium implants with cover screws were used in this study. The length of exposure time ranged from 2 to 15 seconds, and the wattage ranged from 3 to 15 W. A thermocoupler with a module recorder was used to record temperature changes at the implant-cover screw interface with the implant in a 37°C water bath. Temperature changes were documented during the exposure phase, as well as after termination of the exposure. Statistical analysis consisted of analysis of variance (P < .05) for statistically significant differences among the exposure time–wattage pairs. Results. Temperature increases were directly related to wattage and exposure time. All temperatures returned to baseline within 1 minute. Conclusion. Superpulsed CO2 lasers generate significantly less heat with the 15-second, 15-W trial as compared with continuous and pulsed laser modes. Peak temperature increases with similar exposure and wattage times are comparable to those of the pulsed-laser mode. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;88:544-8)

Purpose: This article discusses the development and use of a computerized database to evaluate facial fracture patients. Examples of epidemiologic and treatment outcome analyses that can be performed are also discussed. Materials and Methods: FileMaker Pro 2.1 and 3.0 (Claris Corporation, Santa Clara, CA) for the Macintosh (Apple Computer, Inc, Cupertino, CA) was used for the development of the database. The database contained information on the facial fracture patients treated at The University of Oklahoma Health Sciences Center by the Oral and Maxillofacial Surgery service between January 1, 1994 and December 31, 1996. Eight evaluation forms were used: general information, and mandibular, maxillary, zygomatic, nasal, naso-orbital-ethmoid, orbital, and frontal sinus fractures. Indications for therapy and postoperative complications from the AAOMS Parameters of Care, Section on Trauma Surgery, were also included. Results: This database allowed collection of a vast amount of data on 265 patients. Some of the analyses done on patients with mandibular fractures are described. Conclusion: This computerized database provides a quick and systematic method of obtaining and retrieving information on facial fracture patients. Numerous epidemiologic and treatment outcome analyses can be performed. Overall complication rates based on the AAOMS Parameters of Care are higher than previously published rates because of the longer list of complications being evaluated.

Sinus lift bone grafting has expanded the use of dental implants in reconstructions of the atrophic maxilla. Potential problems include sinus membrane tear, which can lead to graft infection and early failure. Attempts at managing sinus membrane perforations are often limited by difficulty of access, as well as by the friability of the soft tissue lining the sinus. Various techniques have been proposed for managing such membrane tears. The use of fibrin adhesive, however, may present a potential solution in such situations. This article reports our experience with the use of fibrin adhesive in sinus lift procedures, as well as on its autologous preparation.

Purpose: Little research has been done to determine the amount of bone harvested from implant site preparations using an inline bone collector. This study looked at the amount of bone that can be harvested from common dental implant osteotomies. Patients and Methods: A total of 24 implants were placed in 9 patients over a 3-month period. Implant size ranged from 3.75 × 13 mm to 4.75 × 13 mm. Nine implants were placed in the maxilla, and 15 implants were placed in the mandible. Seven patients were female, and 2 patients were male. The patient age ranged from 27 to 72 years. Four patients had implants placed within 5 years after tooth extraction, and 5 patients had implants placed 5 years after tooth extraction: an analysis of variance was used to determine if there were statistical differences between maxilla versus mandible, male versus female, and edentulism less than or greater than 5 years. Results: The average bone volume from the 24 osteotomies was 0.195 ± 0.099 mL. The average osteotomy site measured 4.02 × 12.90 mm. There were no statistical differences noted among maxilla and mandible, gender, or time of edentulism. Conclusions: When using an inline bone collector to harvest implant osteotomy sites, an average of 0.195 mL of bone can be obtained from a site approximately 4.0 × 13 mm. This bone can often be combined with a xenograft or alloplastic material to provide extra bulk to fill peri-implant defects. When multiple implant sites are prepared, often sufficient bone can be obtained with the bone collector alone. © 2001 American Association of Oral and Maxillofacial Surgeons

Hereditary angioedema (HAE) is characterized by sudden attacks of nonpitting edema typically involving the extremities, genitalia, trunk, gastrointestinal tract, face, or larynx. Although attacks often occur withut a trigger, trauma, including surgical procedures, re responsible for 54% of attacks. Dental procedures n particular are high risk for airway obstruction in his disease. Postprocedure swelling may be immeiate or latent for up to 30 hours. Many patients with HAE are denied routine dental care because of the potential for laryngeal swelling after these procedures. Nevertheless, the dental literature provides examples of well-planned tooth extractions in patients with HAE who were given prophylactic treatment with an appropriate medication before the procedure. We report successful prophylaxis using C1 inhibitor (INH) in a 16-year-old female patient with HAE undergoing orthognathic surgery. To our knowledge, this is the first reported case of maxillofacial surgery in a patient with HAE who was given prophylactic treatment with C1 INH.

With the national decline in orthognathic surgery procedures being performed, the specialty must entertain methods of increasing access to this critical service. This report explores the reasons for the decline and the strategies we have used to enhance access in our community.

A modified open condylotomy was used to treat 44 patients who presented with painful temporomandibular joints, and in whom the clinical and arthrographic findings were indicative of disc displacement. A total of 64 joints (20 bilateral) were operated on. Postoperatively, the patients showed an overall improvement in their functional symptoms. Ninety-one percent of patients had improvement in clicking and popping, and 96% reported decrease in locking. Complaints related to pain and headache were improved 85% and 95%, respectively. The modified technique, as well as the anatomic basis for its use, are discussed.

Dental practitioners from time to time must treat patients with epilepsy or similar seizure disorders. This article describes the various classification for epilepsy, explains how such disorders are evaluated and diagnosed, discusses management methods, and addresses related issues for special populations, such as pregnant women and elderly. In addition, the article offers information about what special steps dentists should take in treating such epileptic patients and others vulnerable to seizures and in preparing offices and staff for the possibility that a patient will have a seizure in the office. In general, a patient with severe, poorly controlled epilepsy should be treated in a hospital. Otherwise, a well-controlled patient should easily be treated in the office.

Purpose: This study describes the personal and practice characteristics of oral and maxillofacial surgeons, with an emphasis on gender differences. Potential explanations for differences found are offered. Materials and Methods: A 39-item questionnaire was designed to address areas of suspected differences between male and female oral and maxillofacial surgeons. It included items regarding training, certification, practice type and location, time spent working, practice composition, and personal characteristics. Identical questionnaires were sent to all of the 130 female oral and maxillofacial surgeons (OMSs) registered with AAOMS, as well as to 264 randomly sampled male OMSs. Results: Of the 192 responses received, 109 were from male surgeons, and 83 were from females, 56.8% versus 43.2% of the total. For men, the response rate was 41.3%, whereas the rate was 68.3% for the women; overall, 48.7% of the 394 oral surgeons responded. Profiles of the “average” male and female OMS showed similarities with regard to race, training, and reasons for choosing an OMS career. Age, marital status, number of children, physical characteristics, and use of time outside of work indicated some significant personal differences, as did practice characteristics, including income, number of years in practice, hours spent working, and number of patients seen. Clear gender-based trends were found regarding opinions of physical and mechanical disadvantages, with women more strongly denying such problems. A variety of both positive and negative viewpoints were elicited by the free comment section. Conclusions: Although male and female OMSs are similar with regard to most variables investigated, some significant differences do exist.

Purpose: This study involves the use of magnetic resonance imaging (MRI) to document acute soft tissue injuries involving the temporomandibular joint (TMJ) after condylar fractures. Materials and Methods: Patients with condylar fractures whose clinical and radiographic examinations, as well as the mechanism of their injury, suggested specific damage to the temporomandibular soft tissues underwent MRI scanning. Thirteen patients who met selected criteria were included in this study. Results: Ten patients demonstrated disc avulsion, usually in the anterior or medial direction. Two patients had disruption of the lateral capsule, and one patient showed no MRI evidence of acute injury. Joint effusions were frequently demonstrated. Conclusions: MRI of condylar fractures in those patients with displacement, or in whom the mechanism of injury would predispose them to posttraumatic internal derangement, may assist the clinician in determining whether primary or delayed treatment is indicated. Furthermore, MRI may be a useful resource for enhancing the level of understanding regarding soft tissue changes that occur in the TMJ after acute condylar trauma.