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51.
52.
Among the potential risks of nasotracheal intubation are nasal bleeding, sinusitis, bacteremia, accidental turbinectomy, and some other structural damages. Retropharyngeal dissection is reported as a very rare complication of nasotracheal intubation, mostly encountered in elective surgery patients. A case with traumatic subcondylar fracture of the mandible is presented here, which is suspected to be the cause of the nasopharyngeal dissection that was observed during attempted nasotracheal intubation.  相似文献   
53.
Background: The present randomized, double‐masked, placebo‐controlled, parallel‐arm study examines the impact of adjunctive subantimicrobial‐dose doxycycline (SDD) on the local inflammatory response through cytokine and chemokine levels in gingival crevicular fluid (GCF) samples from patients with chronic periodontitis. Methods: Forty‐six patients with chronic periodontitis received scaling and root planing with or without adjunctive SDD. GCF samples were collected and clinical parameters including probing depth, clinical attachment level, gingival index, and plaque index were recorded every 3 months for 12 months. GCF tumor necrosis factor‐α, interleukin (IL)‐6, IL‐4, IL‐10, IL‐13, IL‐17, macrophage inhibitory protein 1α, macrophage inhibitory protein 1β, monocyte chemoattractant protein 1, and regulated on activated normal T‐cell expressed and secreted protein levels were determined by xMAP multiplex immunoassay. Results: Significant improvements were observed in all clinical parameters in both groups over 12 months (P <0.0125), whereas the SDD group showed significantly better reduction in gingival index, probing depth, and gain in clinical attachment compared to the placebo group (P <0.05). Decrease in IL‐6 in the SDD group was significantly higher compared to the placebo group at 6 and 9 months in deep pockets (P <0.05), whereas tumor necrosis factor‐α was significantly reduced in moderately deep pockets (P <0.05). SDD resulted in a stable IL‐4 and IL‐10 response while reducing the monocyte chemoattractant protein 1 levels at 3 months (P <0.05). Conclusions: These results show that SDD, as an adjunct to non‐surgical periodontal therapy, stabilizes the inflammatory response by promoting the suppression of proinflammatory cytokines and increasing the anti‐inflammatory cytokines. The chemokine activity would account for the regulation of the inflammatory response to SDD therapy.  相似文献   
54.
The Hoffmann (H) reflex is elicited by electrical stimulation of a mixed nerve and is used to measure the excitability of the spindle-motoneuron synapse. Recent investigations have indicated a positive correlation between increases in bite force and H-reflex facilitation. However, these investigations did not examine the H-reflex in detail or the possible role of periodontal mechanoreceptors (PMRs) in this facilitation. The current investigation was performed to determine whether PMRs play a role in H-reflex facilitation during tooth clench (TC). The H-reflex was elicited in the soleus muscle of human subjects while bite level was maintained at rest (0 N), 40 N, 80 N and maximal TC. The front teeth that contributed to the (40 N and 80 N) bite force were then locally anaesthetised (LA), and the protocol was repeated. The current data suggest that the effect of TC on the H-reflex amplitude in the human limb muscles is variable from one subject to the next. Statistical analysis has shown that the H-reflex was significantly smaller during the rest condition than during the 80 N bite (p<0.05) in both non-LA and LA conditions. Since LA did not alter the response, our results do not support that the PMRs play a major role in the facilitation of distal muscle activity.  相似文献   
55.
Objective: The aim of this study was to investigate the possibility of evaluating the relationship between dental maturation and skeletal maturation without taking a hand–wrist radiogram outside of panoramic radiogram. Materials and methods: Panoramic and hand–wrist radiographs of 717 patients (383 girls and 334 boys), with ages ranging from 10 to 15 years, were evaluated. Dental maturity stages of the mandibular canine, first premolar, second premolar and second molar teeth were determined by Demirjian’s and Nolla’s methods. The skeletal maturation was determined by Fishman method and bone age was determined through the Greulich and Pyle method. Results: All teeth showed positive and statistically significant correlations, the highest correlation was between the mandibular second premolar calcification stages and hand–wrist maturation stages. According to both dental age determination methods, mandibular second premolar was prominent in determining to the pubertal growth stages. Conclusions: There was a positive relationship between dental calcification stages and skeletal maturation stages, in the study population. Dental calcification stages of the second mandibular premolar showed the highest positive correlation with the skeletal maturation stages.  相似文献   
56.
Journal of Orofacial Orthopedics / Fortschritte der Kieferorthopädie - Es wurden 72 Fernröntgenprofilaufnahmen von unbehandelten Probanden im Alter von 18 bis 35 Jahren mit anatomisch...  相似文献   
57.
Zusammenfassung Beobachtungen an einigen kieferorthopädischen Fällen lassen erkennen, daß es bei den Milchzähnen neben dem als Halbretention bekannten scheinbaren Tiefersteigen (infolge Verwachsens zwischen Zement und Knochen) auch Retentionen anderer Art gibt. Es handelt sich dabei 1. um verzögerten Durchbruch einzelner Zähne oder Zahngruppen, 2. um echtes Impaktiertbleiben. Ursachen und histologische Besonderheiten werden besprochen.
Summary Observations of some cases in jaw-orthopedics reveal that the deciduous teeth also show other kinds of retentions besides the known half retention — as a result of fusion between cement and bone. First of all it concerns delayed eruption of single deciduous teeth or groups of them, secondly it concerns the fact that they remain actually impacted. Causes and particulars of histology are discussed.

Résumé Des observations de quelques cas d'orthopédie dentofaciale révèlent que les dents temporaires montrent d'autres types de rétention à côté de la semi-rétention réenfoncement connu de la dent (dû à la synostose entre le cément et l'os). Il s'agit de retard d'éruption de


Mit 14 Abbildungen

Herrn Professor Dr. R. Bolle zum 65. Geburtstag  相似文献   
58.
Buchbesprechung     
Ohne Zusammenfassung  相似文献   
59.
summary The aim of this study was to determine the bone density in the designated implant sites using computerized tomography (CT), the fastening torque values of dental implants, and the implant stability values using resonance frequency analysis. Further aim was to evaluate a possible correlation between bone density, fastening torque and implant stability. Eighty‐five patients were treated with 158 Brånemark System implants. CT machine was used for preoperative evaluation of the jawbone for each patient, and bone densities were recorded in Hounsfield units (HU). The fastening torque values of all implants were recorded with the OsseoCare equipment. Implant stability measurements were performed with the Osstell machine. The average bone density and fastening torque values were 751·4 ± 256 HU and 39·7 ± 7 Ncm for 158 implants. The average primary implant stability was 73·2 ± 6 ISQ for seventy implants. Strong correlations were observed between the bone density, fastening torque and implant stability values of Brånemark System TiUnite MKIII implants at implant placement (P < 0·001). These results strengthen the hypothesis that it may be possible to predict and quantify initial implant stability and bone quality from pre‐surgical CT diagnosis.  相似文献   
60.
The periosteum has been referred to as a protective barrier in the regeneration of bone defects. The objective of this study was to determine the contribution of periosteum as a natural barrier to bone formation in guided bone regeneration. Mucoperiosteal flaps were elevated bilaterally on the buccal aspect of the mandibular angle in 5 cynomolgus monkeys. Bleeding was induced by perforating the cortical bone. A hemispherical titanium mesh was fixed over the areas thus creating a void 5 mm in height between the mesh and the bone surface. One one side the mesh was covered with an ePTFE membrane (test side). The contralateral side did not receive further treatment (control side). After 4 month healing, histomorphometric analyses were used to determine the percentage of new bone in the void underneath the mesh, and the ratio between mineralized tissue and marrow spaces in new and old bone. The mean percentage of new bone tissue was 77.2 +/- 7.5% for the test sides and 68.6 +/- 8.4% for the control sides (P = 0.018, t-test). This new bone contained 80.0 +/- 3.6% mineralized tissue in the test group and 82.5 +/- 5.0% in the control group (P > 0.05, t-test). In both groups the newly formed bone exhibited significantly less mineralized tissue than the old bone (P < 0.05, t-test). It is concluded from this study that new bone formation was enhanced by the additional use of an ePTFE membrane under a periosteum-lined mucoperiosteal flap when space maintenance was excluded as a critical factor.  相似文献   
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