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31.
Australia has a unique collection of native fauna, which is often threatened by physical harm or the destruction of its habitat and conservation of endangered species is a primary concern. Investigation of the recent deaths of Bettongs in Lincoln National Park, South Australia was undertaken by the Forensic Odontology Unit, Adelaide University to determine the likely perpetrator. Feral domestic cats were deemed to be responsible, as indicated by bitemarks on the radiotransmitter collars. 相似文献
32.
A simple procedure for construction of a splint for the treatment of burns to the oral cavity has been described. The splint prevents scarring and contracture of the oral opening during healing. 相似文献
33.
Amelogenin, a major structural protein in mineralizing enamel, is also expressed in soft tissues: brain and cells of the hematopoietic system 总被引:1,自引:0,他引:1
34.
35.
DNJ Ricketts EAM Kidd N. Innes J. Clarkson DR GRAHAM J MOUNT AM 《Australian dental journal》2007,52(3):252-253
Background : The treatment of deep dental decay has traditionally involved removal of all the soft demineralized dentine before a filling is placed. However, this has been challenged in three groups of studies which involve sealing soft caries into the tooth. The three main groups either remove no caries and seal the decay into the tooth, remove minimal (ultraconservative) caries at the entrance to a cavity and seal the remaining caries in, or remove caries in stages over two visits some months apart to allow the pulp time to lay down reparative dentine (the stepwise excavation technique). Objectives : To test the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp), progression of decay and longevity of restorations irrespective of whether the removal of decay had been minimal (ultraconservative) or complete. Search strategy : The Cochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PubMed and EMBASE databases were searched. The reference lists in relevant papers were checked. Selection criteria : Randomized controlled trials and controlled clinical trials comparing minimal (ultraconservative) caries removal with complete caries removal in unrestored permanent and deciduous teeth. Data collection and analysis : Outcome measures recorded were exposure of the nerve of the tooth (pulp) during caries removal, patient experience of symptoms of pulpal inflammation or necrosis, progression of caries under the filling, time until the filling was lost or replaced. Due to the heterogeneity of the included studies the overall estimate of effect was calculated using a random‐effects model. Main results : Four studies met the inclusion criteria; two stepwise excavation studies and two ultraconservative caries removal studies. Partial caries removal in symptomless, primary or permanent teeth reduces the risk of pulp exposure. We found no detriment to the patient in terms of pulpal symptoms in this procedure and no reported premature loss or deterioration of the restoration. Authors' conclusions : The results of this systematic review reject the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp) irrespective of whether the removal of decay had been minimal (ultraconservative) or complete and accepts the null hypothesis of no difference in the progression of decay and longevity of restorations. However, the number of included studies is small and differ considerably. Partial caries removal is therefore preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure. However, there is insufficient evidence to know whether it is necessary to re‐enter and excavate further but studies that have not re‐entered do not report adverse consequences. Plain language summary : A systematic review of the literature revealed four studies comparing complete and minimal (ultraconservative) caries removal. It was found that partial caries removal in symptomless, primary or permanent teeth reduces the risk of pulp exposure. We found no detriment to the patient in terms of pulpal symptoms in this procedure. Therefore, partial caries removal is preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure. However, there is insufficient evidence to know whether it is necessary to re‐enter and excavate further but studies that have not re‐entered do not report adverse consequences. 相似文献
36.
Evaluation of collagen/hydroxylapatite for augmenting deficient alveolar ridges: a preliminary report 总被引:2,自引:0,他引:2
D R Mehlisch T D Taylor D G Leibold R Hiatt D E Waite P D Waite D M Laskin S T Smith M M Koretz 《Journal of oral and maxillofacial surgery》1987,45(5):408-413
A multicenter study was undertaken to evaluate a new alveolar ridge augmentation material composed of purified fibrillar collagen and particulate hydroxylapatite (PFC/HA). In a study of 77 patients and 99 reconstructed ridges, this material provided superior handling properties over HA alone as evidenced by its ease of surgical placement and manipulation, and the rarity of particle migration or displacement. Moreover, the rapid development of ridge firmness and stability allowed for the loading of dentures within three to six weeks. Prosthodontist evaluations and surveys of patient satisfaction showed great satisfaction with denture fit, comfort, esthetics, speech, and ability to masticate. 相似文献
37.
Jane E. Risdall Alun J. Carter Emrys Kirkman Sarah A. Watts Christopher Taylor David K. Menon 《Neuromolecular medicine》2014,16(3):606-619
Blast injuries are an increasing problem in military conflicts and terrorist incidents. Blast-induced traumatic brain injury has risen to prominence and represents a specific form of primary brain injury, with sufficiently different physical attributes (and possibly biological consequences) to be classified separately. There is increasing interest in the role of blast in initiating inflammatory responses, which may be linked to the pathological processes seen clinically. Terminally anaesthetised rats were exposed to a blast wave directed at the cranium, using a bench-top blast wave generator. Control animals were not exposed to blast. Animals were killed after 8 h, and the brains examined for evidence of an inflammatory response. Compared to controls, erythropoietin, endothelial integrins, ICAM and sVCAM, and the pro-inflammatory cytokine, monocyte chemoattractant protein-1 (MCP-1) were significantly elevated. Other pro-inflammatory cytokines, including MIP-1α, were also detectable, but levels did not permit accurate quantification. Six inflammatory genes examined by qRT-PCR exhibited a biologically significant increase in activity in the blast-exposed animals. These included genes supporting chemokines responsible for monocyte recruitment, including MCP-1, and chemokines influencing T cell movement. Brain injury is usually accompanied by pathological neuro-inflammation. This study shows that blast brain injury is no exception, and the data provide important mechanistic clues regarding the drivers of such inflammation. Whilst this effect alone is unlikely to be responsible for the totality of consequences of blast brain injury, it suggests a mechanism that may be priming the cerebral inflammatory response and rendering cerebral tissue more susceptible to the deleterious effects of systemic inflammatory reactions. 相似文献
38.
39.
H. A. Fink M. A. Kuskowski J. A. Cauley B. C. Taylor J. T. Schousboe P. M. Cawthon K. E. Ensrud For the Osteoporotic Fractures in Men Study Group 《Osteoporosis international》2014,25(12):2833-2839
Summary
Prior studies suggest an association between stressful life events and fractures that may be mediated by BMD. In the current study, risk of accelerated hip BMD loss was higher in older men with any type of stressful life event and increased with the number of types of stressful life events.Introduction
Prior studies suggest that stressful life events may increase adverse health outcomes, including falls and possibly fractures. The current study builds on these findings and examines whether stressful life events are associated with increased bone loss.Methods
Four thousand three hundred eighty-eight men aged ≥65 years in the Osteoporotic Fractures in Men study completed total hip bone mineral density (BMD) measures at baseline and visit 2, approximately 4.6 years later, and self-reported stressful life events data mid-way between baseline and visit 2, and at visit 2. We used linear regression to model the association of stressful life events with concurrent annualized total hip BMD loss, and log binomial regression or Poisson regression to model risk of concurrent accelerated BMD loss (>1 SD more than mean annualized change).Results
Men (75.3 %) reported ≥1 type of stressful life event, including 43.3 % with ≥2 types of stressful life events. Mean annualized BMD loss was ?0.36 % (SD 0.88), and 13.9 % of men were categorized with accelerated BMD loss (about 5.7 % or more total loss). Rate of annualized BMD loss increased with the number of types of stressful life events after adjustment for age (p?0.001), but not after multivariable adjustment (p?=?0.07). Multivariable-adjusted risk of accelerated BMD loss increased with the number of types of stressful life events (RR, 1.10 [95 % confidence interval (CI), 1.04–1.16]) per increase of one type of stressful life event). Fracture risk was not significantly different between stressful life event-accelerated bone loss subgroups (p?=?0.08).Conclusions
In these older men, stressful life events were associated with a small, dose-related increase in risk of concurrent accelerated hip bone loss. Low frequency of fractures limited assessment of whether rapid bone loss mediates any association of stressful life events with incident fractures. Future studies are needed to confirm these findings and to investigate the mechanism that may underlie this association. 相似文献40.