Facial reconstruction on the abnormal skull model of a living patient.

OBJECTIVE: The concept of using a skull as the armature upon which to reconstruct a face has been understood for many years. The objective of this study was to blindly test this technique by using a skull that was reconstructed from the computed tomography (CT) scans of a living 48-year-old man. DESIGN: The patient had a bilateral cleft lip, alveolus, and palate. A model of the complete skull produced by a computer-controlled milling machine that used data from the CT scans was used for the reconstruction. Surgery was then performed, and new dental prostheses were also constructed. After surgery, a second model of the relevant part of the skull was made and the reconstruction modified accordingly. CONCLUSION: Despite having no information about the patient apart from that which could be gleaned from the model skull, the reconstructions demonstrate the approximate appearance of the face before and after surgery. Even without the extra information routinely available in forensic cases, a face broadly similar to that of the living patient could be achieved.

Hard and soft tissue imaging of the temporomandibular joint 30 years after diagnosis of osteoarthrosis and internal derangement.

PURPOSE: This article describes the clinical and imaging findings in the temporomandibular joints (TMJs) of patients 30 years after the initial diagnosis of osteoarthrosis and internal derangement. PATIENTS AND METHODS: Fifty-five TMJs with a history of osteoarthrosis and internal derangement and 37 contralateral TMJs that were asymptomatic 30 years ago were examined in 46 former patients. To visualize degenerative changes of the bony parts of the TMJ, transpharyngeal and transcranial radiographs were made; to visualize disc position, sagittal T1-weighted magnetic resonance (MR) images were made. For comparison, 22 TMJs of an age-matched control group without complaints related to the masticatory system were similarly examined. RESULTS: Thirty years after the initial diagnosis of osteoarthrosis and internal derangement, clinical signs in former patients hardly differed from those of control subjects. radiographic signs were significantly more common and more severe in former patients. A high percentage of osteoarthrosis and internal derangement was seen on MRI in both TMJs with a history of osteoarthrosis and internal derangement and in the contralateral TMJs. It appeared that osteoarthrosis and internal derangement in the contralateral TMJs had developed asymptomatically in most cases. None of the patients had required treatment for the contralateral TMJ; only one fourth of the patients had noticed symptoms. In the control subjects, osteoarthrosis and internal derangement were infrequently seen. A significant correlation was found between disc position and the severity of radiographically detectable degenerative changes of the TMJ. CONCLUSIONS: It was concluded that 30 years after initial diagnosis there were few clinical signs of osteoarthrosis and internal derangement, although radiographic signs were extensive. Bilateral osteoarthrosis and internal derangement, with one symptomatic and one asymptomatic TMJ, is a common phenomenon. Moderate to severe radiographically detectable degenerative changes may be the only sign of an underlying internal derangement.

[Forensic odontological identification of disaster victims. Experience with the disaster of the Martinair DC-10 in Faro, Portugal]. / Forensisch odontologische identificatie van rampslachtoffers. Ervaringen met de ramp met de Martinair DC-10 te Faro, Portugal.

Forensic odontology plays an important, often decisive role in the identification of disaster victims. In the Dutch situation, the forensic odontologist is part of the Disaster Victim Identification (DVI)-team of the Dutch National Police Force. The extensive experience with forensic odontological identification of disaster victims, gained within the Dutch DVI-team is described and illustrated with reference to the identification procedure following the Martinair DC-10 aircraft crash at Faro, Portugal, december 21st, 1992. In the identification of the total of 56 victims, forensic odontology contributed in 55 cases (98.2%) to the identification; in 40 cases there were such clear agreements that identification based on forensic odontology alone would have been sufficient. The success of the forensic odontological identification method appeared to be greatly dependent of the adequate cooperation of dentists that made their treatment data available for comparison.

[Complete rehabilitation of the secondary cleft lip and palate patient]. / Totale rehabilitatie van de patiënt met secundaire schisis.

This article presents the results of total reconstruction of the 'end stage of cleft lip and palate deformity' in fourteen patients. The deformity consisted of varying degrees of 1. midface retrusion and/or mandibular protrusion; 2 malocclusion; 3. nasal deformity; 4. lip deformity; 5. palate or alveolar fistulas and 6. nasal speech. These deformities resulted in aesthetic and functional problems. By a comprehensive approach in one session--total reconstruction--functional and aesthetic improvement was achieved in all patients.

Histologic evaluation of computed tomographic TMJ articular disk visualization.

The reliability of computed tomography (CT) for visualization of the temporomandibular joint (TMJ) articular disk has often been the subject of discussion. The success or failure of CT may be determined by different factors. This study was designed to evaluate the effect of these factors, such as type of equipment used, patient motion and artifacts on articular disk visualization, and also to assess the validity of the articular disk image in comparison with histological pictures. Ten TMJ autopsy specimens were collected after the teeth were placed in intercuspal position. The TMJ was deep frozen, dissected and kept frozen during subsequent CT scanning and histological processing. To study the influence of the specifications of the CT equipment on the visualization of the TMJ articular disk, two different CT units were used. The CT images were evaluated for interpretability and interpretation of articular disk position. The validity of the CT appearance of articular disk position and form was assessed by superposition of CT and histological pictures. The interpretability of the articular disk visualization in the CT images was very low. However, for CT images judged to be interpretable, there was a good degree of matching between the diagnosed articular disk position and form and the findings in the corresponding histological pictures. No significant differences between the two different CT units were noted. It is concluded that CT is inappropriate for TMJ articular disk visualization. Nevertheless, if the disk is visible on the CT image, its appearance represents the true position and form within the joint.

Computed tomography in differential diagnosis of temporomandibular joint disorders.

Computed tomography (CT) has great potential for imaging intra- and extracapsular hard-tissue abnormality of the temporomandibular joint (TMJ). CT is not the best method of imaging disk position and form. For differential diagnosis of TMJ disorders, CT is especially successful in bony lesions. The study includes 16 examples of TMJ hard-tissue abnormality. In the differential diagnosis of all cases, CT played a decisive role.

[Radiology of the temporomandibular joint. Diagnostic imaging of the temporomandibular joint]. / Röntgenologie van het kaakgewricht. Diagnostische beeldvorming van het kaakgewricht.

Diagnostic imaging plays an important role in the diagnosis of disorders of the masticatory system. The most frequent disorders are osteoarthrosis and internal derangements. The clinical diagnosis of these disorders may be confirmed by diagnostic imaging. In addition, diagnostic imaging contributes to the staging of the degenerative changes. Techniques for examination of the temporomandibular joint, including conventional (panoramic, transpharyngeal, transcranial) as well as more sophisticated techniques (tomography, fluoroscopy, arthrography, computed tomography, scintigraphy and magnetic resonance imaging) are briefly described. The interpretation of the radiological image of the joint in health and when affected by osteoarthrosis and internal derangement is presented.

Classification of temporomandibular joint osteoarthrosis and internal derangement. 1. Diagnostic significance of clinical and radiographic symptoms and signs.

In the clinical setting, diagnosis primarily depends on the history and present status of the patient, and on the examiner's expertise in physical examination and interpretation of conventional radiographs. In order to evaluate the diagnostic significance of clinical and radiographic variables, the authors used magnetic resonance imaging as the 'golden standard' for articular disk position. A total of 90 temporomandibular joints (TMJs) were available for the study. Group I (representing 'normal' disk position) comprised eight joints (8.9%); group II (representing reducing disk), 34 joints (37.8%); and group III (non-reducing disk), 48 joints (53.3%). Nine anamnestic, 15 clinical, and three radiographic variables obeyed pre-defined univariate selection criteria. Relatively high sensitivities were found for clicking-related variables in MR-group II, and for variables related to movement restriction in MR-group III. None of the symptoms or signs appeared to be pathognomonic for either one of the diagnostic groups. Principal component analysis revealed 13 factors that could be grouped into three major categories, representing impairment of joint mechanics, joint pain and tenderness, and radiographically detectable degenerative changes, respectively. Discriminant analyses showed that symptom combinations, which included clinical variables related to joint mechanics, appeared to provide the most useful diagnostic information. It is concluded that reducing and permanent disk displacement can be distinguished in many cases using clinical and radiographic variables. However, there is considerable variability within these groups. To establish a specific clinical diagnosis, a more detailed classification of osteoarthrosis and internal derangement is desirable.

Temporomandibular joint computed tomography: development of a direct sagittal technique.

Radiology plays an important role in the diagnosis of temporomandibular disorders. Different techniques are used with computed tomography offering simultaneous imaging of bone and soft tissues. It is therefore suited for visualization of the articular disk and may be used in patients with suspected internal derangements and other disorders of the temporomandibular joint. Previous research suggests advantages to direct sagittal scanning, which requires special positioning of the patient and a sophisticated scanning technique. This study describes the development of a new technique of direct sagittal computed tomographic imaging of the temporomandibular joint using a specially designed patient table and internal light visor positioning. No structures other than the patient's head are involved in the imaging process, and misleading artifacts from the arm or the shoulder are eliminated. The use of the scanogram allows precise correction of the condylar axis and selection of exact slice level.

Temporomandibular joint direct sagittal computed tomography: evaluation of image-processing modalities.

Computed tomography (CT) is a useful method for examination of the temporomandibular joint because it allows visualization of the articular disk. In computed tomography many factors play an important role in image reconstruction and image processing. The use of image-processing modalities (such as window variation and level detection) has far-reaching consequences on the display and interpretation of the direct sagittal CT image of the temporomandibular joint (TMJ). In this study, the most important image reconstruction and processing factors were studied for use in the diagnosis of internal derangements and other disorders of the TMJ. Optimal values for the setting of the CT system for the different techniques are discussed.