Effects of two gutta-percha formulations and one zinc oxide-eugenol and Canada balsam mixture on human blood monocytes and lymphocytes

Abstract In this study we performed an in vitro assay of the effects of two gutta-percha formulations and one zinc oxide-eugenol and Canada balsam-based endodontic material on the behavior of a mixed cell population of human monocytes and lymphocytes. Cells were cultured either in direct contact with or near experimental samples of Ultrafil, standard gutta-percha cones or Endoseal and the inhibitory effects of these materials upon cell attachment and spreading on test surfaces were analyzed. Ultrafil and the standard gutta-percha cones showed little or no adverse effects, whereas the inhibitory effects of Endoseal appeared to be severe. There were statistically significant differences between the results obtained from both Ultrafil and gutta-percha cones and those obtained from Endoseal. Differences between all tested materials and their respective controls were also statistically significant.     

Bacteriologic status of the root canal after sonic, ultrasonic and hand instrumentation

Abstract The purpose of this study was to assess the bacteriologic status of the root canal after sonic, ultrasonic and hand instrumentation. Root canal infection was induced in 50 single-rooted teeth in young dogs by removing the pulp and filling the canals with dental plaque. After 7 clays the root canals were instrumented under aseptic conditions with conventional hand instruments, a sonic vibratory device or an ultrasonic device. Sterile saline or 2.5% sodium hypochlorite was used as irrigating solution. Following instrumentation a sterile paper point was sealed into the root canals. After 7 d the root canals were reopened under aseptic conditions and the paper points were incubated for the demonstration of bacteria, using pre-reduced thioglycolate culture medium and anaerobic chambers. The results obtained with the different instrumentation techniques and irrigating solutions were compared by means of the Chi-square test. The results indicated that the sonic and ultrasonic devices were not more effective in the elimination of bacteria from the root canal than conventional hand instrumentation. Irrigation with sodium hypochlorite appeared to be more effective than saline in producing bacteria-free root canals; however, this difference was not statistically significant. Thus, it appeared that more than one appointment and the supporting action of an antibacterial medicament between appointments would be necessary to achieve bacteria-free root canals in infected teeth in a predictable manner.     

Distribution of11 C–labelled morphine and pethidine after spinal administration to Rhesus monkey

The kinetics of 11C-labelled morphine and pethidine were studied by positron emission tomography (PET) at different levels of the spinal canal (C4, T4, T5, T6, L1 and L6). Studies were performed in the Rhesus monkey after intrathecal and extradural administration of the drugs at the lumbar level (L3-L4 or L4-L5, seven experiments). Radioactivity 100-300 times higher than with even distribution in the body was measured initially near the site of injection for both morphine and pethidine, irrespective of the route of administration. After injection of pethidine, high activity was observed at the L6 and L1 levels, whilst the radioactive uptake was lower at T6 (10-20% of those at lumbar level). Morphine-derived 11C-radioactivity showed more constant levels along the spinal canal, except at C4 where radioactivity was low. In CSF taken from the cervical level the peaks of radioactivity of the two drugs appeared 80-170 min after injection. The importance of different distribution routes was quantified in a pharmacokinetic compartment model, using the above results. The systemic distribution was extensive, irrespective of drug or route of administration. From the site of injection the systemic distribution was at least 60 times larger than the rostral distribution within the spinal canal.     

Circular enlargement of the optic canal caused by paranasal sinus mucocele

A case of mucocele in the optic canal that caused visual impairment and headache is presented. On the radiograms, the optic canal was concentrically enlarged. There was no such case previously reported.     

Stenosis of the lumbar vertebral canal and sciatica

Summary Stenosis of the vertebral canal is a form of compressive stenosis in contrast to transport stenosis of vessels or other channels. The concept, definition and pathomorphological properties are discussed. As it is a form of compressive stenosis, the diagnosis is based on measurements of diameters rather than of cross-sectional surfaces. The biomechanical action of compressive stenosis is compression of the fixed living content at two opposite sites or at all sites.The special properties of sciatica in stenosis are described and presented in tabular form. Some properties of neurogenic intermittent claudication (I. Cl.) in the presence of stenosis are discussed. There is a predominance of sciatica at rest and of motor weakness during walking. The mechanism of neurogenic I. Cl. is obscure.Stenosis of the lumbar vertebral canal is one of the conditional determinants of I. Cl. The data presented in this paper demonstrate, however, that stenosis is not an absolute determinant of I. Cl. and that its production depends on the combination with other determinants. The theory is advanced that other determinants may be related to changes in the caudal nerve roots due to either constitutional properties or to subclinical changes induced by ageing and chronic wear and tear, and compression and traction in the area of stenosis during various bodily activities. Suppression of sciatica during I. Cl. is a phenomenon which is particularly difficult to explain.Dedicated to Professor K. J. Zülch on the occasion of his 70th birthday.     

The Lumbar Spinal Canal in Hypophosphataemic Vitamin D-resistant Rickets

Abstract: Lumbar spine radiographs of 77 adult patients with hypophosphataernic vitamin D-resistant rickets have been examined and measured in their anteroposterior and transverse dimensions. Comparison of these measurements with those of a group of normal individuals showed the HPR patient group to have narrower spinal canals in both diameters. No differences were found between males and females in either group. The lumbar spinal canal stenosis in adult HPR patients may make them more susceptible to spinal cord compromise from space occupying lesions within the canal, causing back pain and lower limb weakness for which surgical intervention may be indicated.     

Anomalous atlantoaxial portions of vertebral and posterior inferior cerebellar arteries

Summary In a review of the vertebral angiograms of 300 patients free from disease at the craniovertebral junction, we found atlantoaxial arterial anomalies in 2,3%. These were: 2 cases in which the vertebral artery ran in the spinal canal below C1, 3 cases of duplication of the vertebral artery above and below C1, and 2 cases of origin of the posterior inferior cerebellar artery at C2. Although these arteries ran in the spinal canal between C1 and C2, they never encroached upon the posterior third of the canal. From the survey of another 21 patients having bony abnormalities at the craniovertebral junction, the first type of arterial anomaly described above was seen in 4 patients and associated with failure of segmentation of the embryonic sclerotome such as occipitalization of the atlas or Klippel-Feil syndrome. It is possible to relate the development of these anomalous vessels to malarrangement of the embryonic segmental arteries. Our results indicate that one must be cautious with lateral C1/2 puncture or surgical exposure of the region.     

Transsphenoidal meningocele with hypothalamic insufficiency

Summary A 16-year-old girl with transsphenoidal meningocele and signs of hypothalamic insufficiency is presented. Hormonal disturbances have been reported in only three similar cases in the literature. The radiological criteria for the diagnosis are discussed with emphasis on the differential diagnosis of a persistent craniopharyngeal canal. Based on the present case and studies of the pertinent literature we propose that all patients exhibiting signs of dysraphism of the base of the skull should be thoroughly investigated for hormonal disturbances. Children with cleft palate should be examined for possible concomitant dysraphism of the skull.     

The midline suboccipital subtonsillar approach to the hypoglossal canal: surgical anatomy and clinical application

Summary Primary lesions of the hypoglossal canal, such as hypoglossal schwannomas, are rare. No consensus exists with regard to the surgical approach of choice for treatment of these lesions. Usually, lateral transcondylar approaches have been used. The authors describe the surgical anatomy of the midline subtonsillar approach to the hypoglossal canal. This approach includes a midline suboccipital craniotomy, dorsal opening of the foramen magnum and elevation of ipsilateral cerebellar tonsil to expose the hypoglossal nerve and its canal. The midline subtonsillar approach permits a straight primary intradural view to the hypoglossal canal. There is no necessity of condylar resections. The surgical anatomy of the subtonsillar approach is described and illustrated by an example of a case.     

Innovative wavelengths in endodontic treatment

BACKGROUND AND OBJECTIVES: The sanitation of the root canal system and the adjacent dentin has always been a key requirement for successful endodontics. In recent years, various laser systems have provided a major contribution to this aim, namely the Nd:YAG-, the 810 nm Diode-, the Er:YAG-, and the Er,Cr:YSGG laser. Numerous studies could prove their efficiency within the endodontic procedure. Recently, two new wavelengths have been introduced to the field of oral laser applications: The KTP laser emitting at 532 nm and the 980 nm diode laser. The present in vitro investigation was performed to evaluate the effects of these laser systems focusing on their antibacterial effect in deep layers of dentin and their impact on the root canal dentin. STUDY DESIGN/MATERIALS AND METHODS: Two-hundred slices of root dentin with a thickness of 1 mm were obtained by longitudinal cuts of freshly extracted human premolars. The samples were steam sterilized and subsequently inoculated with a suspension of either Escherichia coli or Enterococcus faecalis. After the incubation, the samples were randomly assigned to the two different laser systems tested. Each laser group consisted of two different operational settings and a control. The dentinal samples underwent "indirect" laser irradiation through the dentin from the bacteria-free side and were then subjected to a classical quantitative microbiologic evaluation. To assess the temperature increase during the irradiation procedure, additional measurements were carried out using a thermocouple. To assess the impacts on the root canal walls, 20 additional samples underwent laser irradiation at two different settings and were subjected to scanning electron microscopy. RESULTS: Microbiology indicated that both laser systems were capable of significant reductions in both test strains. At an effective output power of 1 W, E. coli was reduced by at least 3 log steps in most of the samples by the tested wavelengths, with the best results for the KTP laser showing complete eradication of E. coli in 75% of the samples. E. faecalis, a stubborn invader of the root canal, showed minor changes in bacterial count at 1 W. Using the higher setting of 1.5 W, significant reductions of E. coli were again observed with both laser systems, where the lasers were capable of complete eradication of E. faecalis to a significant extent. There was no significant relation between the temperature increase and the bactericidal effect. CONCLUSIONS: The present study demonstrates that both wavelengths investigated could be suitable for the disinfection of even the deeper layers of dentin and equal the results achieved by established wavelengths in state-of-the-art endodontics.