Biomedical subjects
Publications and source records attributed to S Johannessen.
Cemento-ossifying fibromas are slow growing, benign lesions. Recurrence is considered rare. A mandibular periapical radiolucent lesion in a 30-year-old female was diagnosed histologically as a cemento-ossifying fibroma and excised. A recurrence was found 2 years and 6 months postoperatively. CT demonstrated that the recurrent lesion was larger than indicated by conventional radiography.
PURPOSE: To describe CT appearances in patients with unilateral cleft lip and palate (CLP) 20 years after bone graft surgery. MATERIAL AND METHODS: Eighteen consecutive patients with unilateral CLP were examined. All patients had been treated with primary closure, both in infancy and early childhood, supplemented with bone grafting at the age of around 10 years. The CT examination of the upper jaw included a dental CT program. The CT appearances of the cleft side were compared with those of the untreated non-cleft side. RESULTS: Abnormal CT appearances included skew nasal aperture (n=17), nasal septal deviation (n=17), low floor of nasal aperture (n=15) at or towards the cleft side, and deviation of anterior nasal spine towards the non-cleft side (n=18). The posterior part of the bone cleft was visible in all patients, and the dental arch was V-shaped in 8. CONCLUSION: Although adherence to the present treatment protocol is considered to give satisfactory functional and cosmetic results, certain abnormalities persist. A knowledge of these is a prerequisite for a complete and final evaluation of the surgical and orthodontic regimen.
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OBJECTIVE: The purpose of this study was to present a newly developed ortho cubic super-high resolution computerized radiographic technique (Ortho-CT) and its application to the temporomandibular joint. METHOD AND PATIENTS: A prototype was assembled on a Scanora (Soredex Findent Co) with the use of a 4-inch image intensifier instead of film. Data were collected from a single 360 degrees scan and a cylinder 32 mm in height and 38 mm in diameter. Images were reconstructed with a software program on a personal computer. Imaging data consisted of 240 (height) x 280 (diameter) cubic voxels, each with a dimension of 0.136 mm. With this small voxel size, the image resolution was high and was the same in any direction. Three patients with temporomandibular joint disease (trauma, pain and dysfunction, fibroosseous ankylosis) were evaluated with Ortho-CT, and the images were compared to routine radiographic films. CONCLUSION: Preliminary clinical experience with Ortho-CT demonstrates subjectively superior image quality compared to panoramic and conventional tomographic images. The images were similar to conventional computed tomography, but this new radiographic technique is less expensive, takes less space, and gives a lesser patient dose.
The clinical, radiological, histopathological and immunohistochemical (cytokeratin) features of two cases of glandular odontogenic cyst (GOC) are presented and discussed in a review of 45 cases of GOC hitherto reported. Of cases with available information, 34 occurred in the mandible and 6 in the maxilla; the male:female ratio was 19:28, and the mean age was 46.7 years in males and 50.0 years in females. Six cysts recurred once after 2-8 years (mean 2 years 8 months) and 2 (5.3%) recurred twice after 2 and 5 years and after 3 and 5 years, respectively, giving a rate of recurrence of 21%. The identification of osteodentin in one of the present cases and the co-expression of cytokeratins (CK) 13, 19 and 8 strongly support the concept of odontogenic differentiation in the GOC. Careful surgical removal of the lesion succeeded by a 5-year follow-up period is recommended.
Ectodermal dysplasias (EDs) are a group of developmental disorders (more than 100) mainly affecting ectodermal tissues and organs. The X-linked hypohidrotic ED (HED) is the most common form of EDs, involving defects in teeth, sweat glands, and hair. In a few reports, HED has been associated with reduced salivary function. In the present case report, a dramatically reduced salivary fluid and acidic proline rich protein production was identified in a 38-year-old man with HED. Computed tomography was performed, revealing that one submandibular gland and both parotid glands were hypoplastic, whereas the right submandibular gland seemed to be absent. These findings are in line with a general developmental disturbance also involving the salivary glands. As salivary tests are inexpensive and easy to perform, it is suggested to routinely evaluate salivary secretion in persons with HED, to prevent a possible negative impact on oral health.
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The introduction of standardised data-collection forms and computer-aided diagnosis has been found to be associated with improved diagnosis and management of patients with acute abdominal pain. The mechanism by which such benefits accrue has been the subject of some controversy. Detailed analysis of 5193 patients from one hospital shows that the major benefit from such diagnostic aids was the accurate early diagnosis of non-specific abdominal pain by senior house officers in the accident and emergency department; this in turn led to fewer admissions and fewer operations with negative findings. Clinical data about patients with acute abdominal pain should be recorded on structured information sheets by junior doctors and early positive diagnosis should be encouraged before decisions affecting the patient's management are made. Improved computer support may confer further benefits.
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The precision of tooth-length assessments based on repeated panoramic radiographs made with a Siemens OP 5 was investigated in three groups of twenty patients. Two exposures of the same patient were made under three different radiographic conditions. Of the tooth lengths, nonmeasurability was found in 14% to 17%. The variability (standard deviation) of the measurements assessed from repeated radiographs ranged from 0.65 to 0.85 mm, or 2.4% to 3.1% of the mean radiographic tooth length in the different patient groups. The measurement error ranged from 0.43 to 0.56 mm, indicating that the main source of error inherent in the method was recognition of the reference points. Small differences were found between the tooth groups and between the right and left sides.
The performance of a new enzyme multiplied immunoassay technique (EMIT) was compared with other current methods, namely gas-liquid chromatography and thin-layer chromatography, for the determination of phenytoin and phenobarbital in serum. Forty-three serum samples were sent as unknowns to the participating laboratories for determination. The precision of repeated determinations was very similar for EMIT and chromatography. There was good agreement among gas chromatography, thin-layer chromatography, and EMIT results. Interlaboratory variability was lower for EMIT determinations of both antiepileptic drugs. The rapid analysis of small samples, made possible by the EMIT system, could have beneficial effects on the treatment of epilepsies.
19 pooled plasma specimens were sent as unknowns to 13 participating research laboratories. The interlaboratory variability between the results was very high. Only 4 out of 13 laboratories had 6--12% of their results within the 95% confidence limit for each sample. The precision of repeated determinations was fairly good. 6 out of 10 participating laboratories had a coefficient of variation of less then 5%. The reproducibility and the agreement between the different procedures for quantitative analysis of dipropylacetate is similar to that reported for other major antiepileptic drugs.
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Transpharyngeal examination of the mandibular condyle was compared with transcranial and transmaxillary examinations in 22 patients with mandibular pain/dysfunction. All projections were supplementary and a combination of at least two methods seemed preferable. When a single examination was used, underestimation of abnormalities was evident. In demonstrating condylar destruction, the transpharyngeal examination seemed to be superior to the more commonly used transcranial, but inferior to the transmaxillary examination.