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Linear (two-dimensional) and three-dimensional (3D) plating systems (Poly-Medics) composed of the resorbable copolymer of polyglycolic acid (PGA) and poly-l-lactic acid (PLLA) (Lactosorb) were studied in vitro. The plates were applied to osteotomized fresh frozen human cadaveric metacarpal bones that were then tested for torsional rigidity and three-point bending strength and rigidity. The results were compared to those from another study of two low-profile titanium plating systems (Leibinger and Synthes). Analysis of variance revealed that the linear-flat Lactosorb plate and screws had apex dorsal rigidity and force-to-displacement measurements equal to all but two of the titanium plates (3D). The 3D-flat Lactosorb plate had the highest torsional rigidity of the resorbable system, but it was only moderately rigid compared to the titanium plating systems. This in vitro biomechanical study of the copolymer PGA-PLLA plating system indicates that, in clinical applications, it may be better suited for metacarpal fractures rather than proximal phalangeal fractures due to the lower demands of torsional loading compared to apex bending.

The concept of biodegradable bone fixation devices, which provide sufficient rigidity to allow fracture healing and resorption thereafter, has significant appeal in cranio-maxillofacial trauma treatment; however, biodegradable bone fixation devices have not yet become available for clinical use in the craniofacial skeleton. This article reviews the obstacles in developing a resorbable polymer bone fixation system and describes the initial use of such a system in the treatment of cranio-maxillofacial trauma patients. It also discusses the potential role of a resorbable polymer bone fixation system in conjunction with the use of metal fixation in the management of facial fracture.

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.

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.

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.

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.

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.

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.

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.

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.

The purpose of this study was to compare short-term (approximately 12 months postoperatively) and long-term (24 to 81 months postoperatively) records of 36 patients who underwent superior repositioning of the maxilla via LeFort 1 osteotomies. The parameters of measurement were set up to analyze the net response of the soft tissues of the face to superior repositioning of the maxilla. The results of this study show that soft-tissue changes associated with maxillary impaction are minimal and that no significant differences exist between twelve-month records and five-year records.

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.

Computerized video imaging techniques that enable superimposition of cephalometric radiographs and tracings on the image of the soft tissue profile are presented. This superimposition allows visualization of the underlying skeletal and dental hard tissues as they relate to the profile and permits surgical planners to be more cognizant of the limitations that the teeth and occlusion present as the esthetic treatment goals are defined. Step-by-step treatment planning of a patient is used to demonstrate the techniques.

This study was designed to describe short- and long-term soft tissue profile changes that follow surgical advancement of the mandible, to provide a database for prediction of facial changes following surgery. A number of hard and soft tissue landmarks were identified on serial cephalometric tracings of 31 patients. The long-term data (x = 14.0 months postsurgery) showed that changes in soft tissue landmarks overlying the skeletal structures followed their hard tissue counterpart in a 1:1 ratio in the horizontal direction. Horizontal hard to soft tissue landmark changes between mandibular incisor and lower lip, however, were found to be different; the average ratio was 0.43:1.00. Short-term data (x = 2.7 months postsurgery) showed soft tissue changes to be stable when compared to long-term changes.

Non-A non-B (NANB) hepatitis has at least two distinct causative agents. NANB hepatitis can lead to chronic liver disease, cirrhosis, and hepatocellular carcinoma. No definitive policy exists to exclude this disease as a cause of posttransfusion hepatitis. Delta agent is epidemiologically linked to hepatitis B virus (HBV) infection, either as a coinfection or as a superinfection in chronic hepatitis B surface antigen carriers. Recognition of hepatitis due to delta agent will probably increase as testing for this agent becomes more available and its presence becomes more generally well known throughout the medical profession.

This study examines the relationship between facial morphology and nasal respiration. Nasal resistance to expiratory airflow, average volume flow rate, and temporal characteristics of the respiratory cycle were measured for twenty-eight adults. Subjects were categorized as having (1) normal facial proportions with competent lips (n = 10), (2) normal facial proportions with incompetent lips (n = 9), and (3) long vertical face height (n = 9). Results indicate that the three groups do not differ significantly in terms of nasal airflow. Lip incompetence is not synonymous with mouth breathing. Although long-faced subjects as a group had a higher mean value of nasal resistance, the range of variation was so great as to preclude the diagnosis of nasal obstruction from an assessment of facial morphology.

With the advancements of computer knowledge today, treatment planning and counseling are becoming more efficient by means of video imaging. Using a video image of a patient, esthetic and functional decisions can be made by the surgeon, orthodontist, and patient in a consensus manner. Distortion characteristics of video hardware, software, and the video camera are established, and adoption of imaging techniques is employed to maximize accuracy of the imaging process. Patients' attitudes toward video imaging concerning expectations, value of visual prediction, and degree of realism are also discussed. This study is intended to establish some of the basic goals of video imaging with general information in regard to hardware and software requirements.

The purpose of this study was to determine whether anterior and inferior displacement of the maxilla seen with rapid palatal expansion when done with a banded rapid palatal expansion appliance is significantly different from an occlusally bonded rapid palatal expansion appliance. It was hypothesized that the bonded appliance would limit unwanted displacement of the maxilla by producing vertical forces on both arches in a manner similar to a functional appliance. The study was conducted using the bonded appliance on 20 adolescents and comparing the results with those of a banded appliance population--namely, 60 cases from Wertz's study. Lateral cephalometric radiographs were taken before treatment and again after the expansion appliances were removed. The results of this study suggest that the downward and anterior displacement of the maxilla often associated with the banded rapid palatal expansion appliance may be negated or minimized with the more versatile bonded appliance.

22 septorhinoplasties were performed in conjunction with orthognathic surgery, and followed for at least 12 months. No significant difference could be established between 15 cases done with a LeFort I and 7 cases done with isolated sagittal split osteotomies. Rigid bicortical fixation of the mandible was required to change the endotracheal tube from nose to mouth. Plating of the maxilla is recommended to achieve a stable bony support for the nose. Patient satisfaction and perception were surveyed. Clinical results are presented with pre- and post-operative photographs, along with mean data for the total group.

Cefoperazone, a third-generation cephalosporin derivative, has been reported to have excellent antibacterial activity against a wide range of gram-positive and gram-negative pathogens, including Pseudomonas aeruginosa. We treated 54 patients with a variety of clinical infections with cefoperazone and determined the susceptibilities of their 90 bacterial isolates. An additional 25 aerobic isolates obtained from patients treated with cefamandole in a comparison study were also tested for susceptibility to cefoperazone. Thus a total of 115 isolates were studied in vitro. One hundred nine (95%) of 115 bacterial isolates, including gram-positive and gram-negative aerobes and anaerobes, were susceptible to less than or equal to 32 microgram/ml. Only four isolates (three Escherichia coli and one Serratia marcescens) were highly resistant (minimal inhibitory concentration greater than or equal to 128 microgram/ml). We were able to assess clinical outcome of cefoperazone therapy in 53 patients; favorable responses (cure of improvement) were found in 48 (91%). P. aeruginosa was a major pathogen in three patients treated with cefoperazone; all three showed a favorable response. Side effects of cefoperazone therapy were noted in seven (13%) patients, and laboratory abnormalities were observed in 11 (20%) patients; all of these were mild and readily reversible. Cefoperazone thus appears to be safe, well tolerated, and suitable for use in a variety of human infections.

65 aphakic patients (89 eyes) wore extended wear contact lenses for an average period of 22.8 months. 74% of the patients developed one or more readily detectable ocular changes during the course of the study. These complications, their frequency, cause and management are described and discussed. In spite of the large number of complications, 82% of the patients were still wearing lenses at the termination of the study period. None of the complications were serious enough to produce ocular tissue damage that resulted in any permanent loss of vision. Careful patient management and frequent follow-up visits were the key to achieving successful wearing results.

As is evident from the foregoing discussion, hepatitis A and hepatitis B are not static, passé disease. Knowledge concerning these illnesses continues to expand at a fantastic rate--all of it of extreme practical clinical significance. Most interesting is the elucidation of the etiology of the acquired immune deficiency syndrome (AIDS) and the increase this knowledge is hoped to produce on the utilization of hepatitis B vaccine. Also extremely important is the development of recombinant DNA vaccine, which will permit total circumvention of the question of AIDS and safety of the hepatitis B vaccine.