Kiefergelenkbeschwerden bei juvenilen Patienten mit rheumatischen Erkrankungen

Fragestellung

Ziel der Untersuchung war es, die Häufigkeit von klinischen Kiefergelenkbeschwerden bei Kindern mit rheumatischen Erkrankungen zu erfassen und Zusammenhänge zwischen dem Stadium der rheumatischen Erkrankung und dem klinischen Bild einer Kiefergelenksymptomatik zu evaluieren.

Material und Methodik

Im Rahmen einer prospektiven Untersuchung wurden die Kiefergelenke von 48 Kindern mit einer rheumatischen Erkrankung klinisch untersucht. Folgende Parameter wurden evaluiert: Knacken, Reibegeräusche, Druckdolenzen, Dauer der rheumatischen Erkrankung sowie die Anzahl der betroffenen peripheren Gelenke. Das Stadium der rheumatischen Erkrankung wurde mit Hilfe der Steinbrocker-Klassifikation erfasst.

Ergebnisse

Insgesamt wiesen 26 Patienten (54,17%) eines oder mehrere der o. g. Kiefergelenksymptome auf. Der Chi-Quadrat-Test ergibt keine signifikanten Zusammenhänge zwischen dem Grad der Steinbrocker-Klassifikation und dem Auftreten pathologischer Befunde am Kiefergelenk. Eine erhöhte Anzahl der von der rheumatischen Erkrankung betroffenen Gelenke führt nicht zu einem signifikanten Anstieg von pathologischen Kiefergelenkbefunden. Es zeigt sich jedoch ein signifikanter Zusammenhang zwischen der Erkrankungsdauer und dem Auftreten pathologischer Kiefergelenkerscheinungen. Knack- und Reibegeräusche kommen mit zunehmender Erkrankungsdauer signifikant häufiger vor (p=0,011).

Schlussfolgerung

Kinder mit rheumatischen Erkrankungen neigen häufiger zu Kiefergelenkerkrankungen als Kinder ohne rheumatische Erkrankungen. Mit Fortdauer der rheumatischen Erkrankung steigt die Inzidenz pathologischer Kiefergelenksbefunde.     

Evaluation of pluronic polyols as carriers for grafting materials: study in rat calvaria defects

BACKGROUND: Pluronic polyols are a family of non-ionic surfactants currently used as drug carriers for antibiotic, anti-inflammatory, and anti-neoplastic agents. Therapeutic administration of non-ionic surface-active agents is known to facilitate early collagen synthesis and microcirculation, thus promoting wound healing. The purpose of this study was to determine the in vivo effects of pluronic polyols combined with either an allograft or an alloplast on the healing of critical-sized calvarial defects. METHODS: One hundred fifty (150) adult (95 to 105 days old) male Sprague-Dawley rats weighing between 375 and 425 g were randomly and evenly assigned to each of 15 separate treatment groups and anesthetized, and 8 mm calvarial critical-sized defects were created. Pluronic F-68 (F-68) or pluronic F-127 (F-127) was administered either topically or systemically and in conjuction with demineralized bone powder (DBP), tricalcium phosphate (TCP), or non-grafted controls. Pluronic polyols are easily mixed with either DBP or TCP to improve handling ease. Calvaria were harvested at 12 weeks postsurgery and evaluated histomorphometrically, by contact radiography with subsequent densitometric analysis, through energy spectrometry utilizing a scanning electron microscope, and by fluorescent microscopy. RESULTS: There was a significant difference in the percentage of bone fill among the control, TCP, and DBP only groups, P <0.05. The only significant difference within any of these groups was between the TCP control and TCP plus systemic F-127, P<0.05. CONCLUSIONS: Although there were isolated differences, the overall trend was that the pluronic polyol and the mode of administration did not result in a significant change in bone wound healing as measured by the percentage of bone fill. Pluronic polyols may be considered as carriers for osseous graft materials.     

Effect of caries disclosing agents on bond strengths of total-etch and self-etching primer dentin bonding systems to resin composite

This study examined the effect of caries disclosing dyes on composite to dentin shear bond strengths of a total etch, one-bottle and two self-etching, non-rinsing primer dental adhesives. Two caries disclosing dyes were evaluated, Seek and Snoop, with three dentin adhesives, Prime & Bond NT, Prompt L-Pop and Clearfil SE Bond. Extracted human molars stored in 0.2% sodium azide were sectioned longitudinally to expose dentin and embedded in acrylic, leaving the dentin exposed. Each dentin adhesive had three test groups (n=12); a control and one with each of the caries disclosing dyes. The control group had the dentin conditioned and the adhesive applied following the manufacturer's instructions. The caries disclosing dye groups had the dentin first treated for 10 seconds with the disclosing dye, rinsed, then the dentin adhesives were applied as in the controls. A column of Tetric Ceram was bonded after dentin adhesive placement to each specimen and light cured. Specimens were stored in room temperature water for 24 hours, thermocycled for 1,000 cycles between 5 degrees C and 55 degrees C and tested in shear until failure. Mean +/- SD shear bond values (SBV) were determined in MPa. A one-way ANOVA and Student Neuman Keuls multiple comparison test within each DBS were performed at a significance level ofp<0.05 to analyze the caries disclosing dyes input on SBV versus the controls. Surface analysis to determine the nature of the type of dentin/composite fracture/ separation was also performed. For the fracture analysis data, a Chi-Square test was performed at a significance level of p<0.05. The results of this study indicate that using the two tested caries disclosing dyes, with a total etch, one bottle and two self-etching, non-rinsing primer dental adhesives did not negatively affect the dentin-to-composite shear bond strengths of the three tested dentin bonding systems (p>0.05).     

Bone scintigraphy as an adjunct for the diagnosis of oral diseases

Bone scintigraphy is a very sensitive method for the detection of osteoblastic activity of the skeleton. The technique consists of imaging the uptake of bone-seeking radiopharmaceuticals, particularly technetium-99m labeled diphosphonates, in the mineral component of bone, which consists of hydroxyapatite crystals and calcium phosphate, as well as in the organic matrix such as collagen fibers. Plain radiographs, computed tomography, and magnetic resonance imaging are classified as structural imaging modalities, whereas bone scintigraphy is a functional method. In many cases, radionuclide imaging techniques are the only means by which early physiologic changes that are a direct result of biochemical alteration may be assessed, before significant bone mineral changes can be detected by other means. Since many oral diseases may cause metabolic changes in the oromaxillofacial complex, it would be of great value to use bone scintigraphy to evaluate more completely some conditions involving the bones in the region to formulate more appropriate treatment plans. Based upon the current literature, the authors discuss the possible applications of bone scintigraphy as a diagnostic and treatment planning adjunct for oral diseases. Bone scintigraphy has proven particularly useful in the study of malignant lesions and in the evaluation of vascularized bone grafts used for maxillofacial reconstructions.     

A case of bitten Bettongs

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.     

Steady-state and pulsed current multi-ion simulations for a thallium electrodeposition process

A numerical simulation and optimization tool for pulsed current electroplating processes is applied to the industrial preparation of high quality Tl-203 deposits. Reliable predictions on current efficiency and deposit quality are enabled by the construction of an adequate reaction mechanism for Tl deposition from highly basic solutions (pH >12.5) in the presence of the EDTA complexing agent. In order to account for multi-ion mass transfer effects near the electrode, the diluted electrochemical ionic system model is to be solved without simplifications, in combination with electron transfer and homogeneous complex forming reactions as defined by the proposed reaction mechanism. Physical and chemical parameters for this model are achieved by comparing and tuning simulated steady-state polarization and efficiency curves at a rotating disc electrode (RDE) with experimental data.     

Infection-mediated early-onset periodontal disease in P/E-selectin-deficient mice

BACKGROUND: Retrospective and correlation studies suggest that early-onset periodontal disease may be due to a deficiency in phagocyte function, a pathogenic oral biofilm, and/or dysregulated gingival cytokine expression. Increased susceptibility to periodontal disease is therefore thought to result from multiple risk factors. METHODS: We tested this hypothesis prospectively using P/E-selectin adhesion molecule deficient mice that mimic the human syndrome leukocyte adhesion deficiency II. RESULTS: Our studies demonstrate that, in comparison to wild type animals, P/E-/- mice exhibit: spontaneous, early onset alveolar bone loss which is significant by 6 weeks of age; a 10-fold elevation in bacterial colonization of their oral cavities; and elevated gingival tissue levels of the bone resorptive cytokine IL-1alpha. Alveolar bone loss is completely prevented by prophylactic antibiotic therapy. CONCLUSIONS: These experiments provide the first prospective evidence for the multiple risk factor hypothesis of periodontal disease, and validate the first animal model for early onset periodontitis in which both the microbiota and host response can be systematically manipulated. P/E-/- animals should be useful in testing the virulence of putative periodontal pathogens, in determining the role of host resistance factors in periodontitis, in exploring the proposed relationship(s) between infection mediated alveolar bone loss and systemic health disorders, and exploring their genetic relationships.     

In vitro assessment of the antimicrobial action and the mechanical ability of chlorhexidine gel as an endodontic irrigant

The objective of this study was to assess the chlorhexidine gluconate gel as an endodontic irrigant. First the ability of chlorhexidine gel to disinfect root canals contaminated in vitro with Enterococcus faecalis was investigated. A scanning electron microscope was also used to evaluate its cleansing ability compared with endodontic irrigants commonly used, such as sodium hypochlorite and chlorhexidine gluconate liquid. The results indicated that the chlorhexidine gel produced a cleaner root canal surface and had an antimicrobial ability comparable with that obtained with the other solutions tested. It was concluded that chlorhexidine gluconate in gel form has potential for use as an endodontic irrigant.     

Composite autogenous bone and demineralized bone matrices used to repair defects in the parietal bone of rabbits

We compared the amount of new bone produced by endochondral and intramembranous autogenous bone grafts in the presence of demineralized bone matrices (DBMs) prepared from intramembranous bone (DBM(IM)) or endochondral bone (DBM(EC)). Thirty-five bone defects were created in the parietal bone of 20 New Zealand White rabbits. In the experimental groups, 5 defects were grafted with endochondral bone, 5 with endochondral bone mixed with DBM(IM)) (EC-DBM(IM)), 5 with intramembranous bone mixed with DBM(IM)(IM-DBM(IM)) and 6 with endochondral bone mixed with DBM(EC)(EC-DBM(EC)). In the control groups, 10 defects were left alone (passive control) and 4 were grafted with rabbit skin collagen (active control). They were all killed on day 14 and the defects were prepared for histological study. Serial sections were cut across the whole defect. Quantitative analyses were made on 202 sections of the experimental groups by image analysis. A total of 414%, 708%, and 85% more new bone was formed in defects grafted with composite EC-DBM(IM), IM-DBM(IM)and EC-DBM(EC), respectively, than those grafted with endochondral bone alone (P<0.001). No bone was formed in either passive or active controls. In conclusion, demineralized bone matrices, particularly those derived from intramembranous bone, have extremely high osteoinductive properties and greatly improve the integration of autogenous bone grafts in the skull.     

Developments in shrinkage control of adhesive restoratives

PURPOSE: This article reviews material properties and application techniques important in minimizing effects of polymerization shrinkage during the curing reaction of resin composite restorative materials used in adhesive dentistry. MATERIALS AND METHODS: Relevant scientific publications were critically reviewed. RESULTS: Since it was recognized that shrinkage, which takes place during the curing reaction of resin composite restorative materials, may cause severe problems in adhesive dentistry, considerable effort has been put into reducing the negative effects. The most important problem is the debonding of the restoration-tooth interface, resulting in increased microleakage and, ultimately, in secondary caries. Despite all efforts, there is still no material or general application method that guarantees a leak-proof and durable restoration. CLINICAL SIGNIFICANCE: It is of the utmost importance that dental practitioners know how to deal with the problems related to resin composite shrinkage, so that they can choose the material and procedure most likely to produce a leak-proof and durable restoration, maximizing the potential for clinical success.