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Effects of smoking on resorption of the residual alveolar ridges in complete denture wearers  

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Full Text Available Introduction Based on literature data it is obvious that there is a connection between smoking and periodontal diseases. Alveolar bone loss increases with smoking. Tobacco smoking affects the proportion of subgingival bacterial flora by influencing oxidoreduction potential of dental plaque and thus making conditions for development of anaerobic bacteria. According to some researchers, smoking affects the mineral component of bone tissue. Orthopantomograms show higher level of alveolar bone loss in smokers than in nonsmokers with the same level of oral hygiene. The aim of this study was to establish if smoking affects alveolar bone loss in complete denture wearers. Material and methods Our clinical investigation included 60 patients of both sexes (30 smokers and 30 nonsmokers all complete dentures wearers. All patients met study criteria: jaw relation and smokers who smoke over 20 cigarettes per day. All subjects were interviewed, and after that orthopantomograms were made. They were used to calculate the degree of alveolar bone loss. Results The examined subjects were approximately of the same age. Mean age of smokers was 59.9 and nonsmokers 61.8. It was established that differences regarding resorption in men were not significant. The degree of resorption in women smokers and women nonsmokers was different, but differences were not significant. Discussion It has been proven that the number of cigarettes smoked per day is very important. It is considered that the risk of oral epithelial dysplasia increases when smoking more than 20 cigarettes per day. Considering our results regarding resorption of edentulous alveolar ridge in smokers and nonsmokers, we concluded that there were no significant differences. There are opinions in literature that smoking is not an etiological factor in resorption, but there are some opinions that smoking is connected with the degree of resorption in periodontium. The analyses of resorptive changes in edentulous smokers were done only around implants and it was estimated that smoking has more influence than other clinical risk factors. Conclusion On the bases of our research we may conclude that smoking does not directly affect the degree of resorption of edentulous alveolar ridge with complete denture wearers.

Markovi? Dubravka

2003-01-01

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Alveolar ridge resorption after tooth extraction: A consequence of a fundamental principle of bone physiology  

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Full Text Available It is well established that tooth extraction is followed by a reduction of the buccolingual as well as the apicocoronal dimension of the alveolar ridge. Different measures have been taken to avoid this bone modelling process, such as immediate implant placement and bone grafting, but in most cases with disappointing results. One fundamental principle of bone physiology is the adaptation of bone mass and bone structure to the levels and frequencies of strain. In the present article, it is shown that the reduction of the alveolar ridge dimensions after tooth extraction is a natural consequence of this physiological principle.

Stig Hansson

2012-08-01

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Degree of the residual alveolar ridge resorption registrated by ortopantomograms among immediate and classic complete denture users  

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Full Text Available Degree of residual ridge loss is influenced by sistemic phactors, but during the first phase after extraction local phactors are dominant. Patohistological changes of alveolar processus of jaws show the possibility of negative influence of complete dentures on support tissue. In this study, on the chosen sample, the degree of alveolar ridge loss was measured in the group of immediate complete denture users (30 patients and classical complete denture users ( 30 patients.Height of residual alveolar ridge was measured on ortopantomograms. Localization of referent points proportion was used because of neutralization of shadow distorsion (five in maxilla and five in mandibula. The first ortopantomogram was made at the time of delivering dentures, and the second one six months later. The final measurement of alveolar ridge height is bigger in the group with classical dentures. The reduction degree of residual alveolar ridge is bigger in the group of immediate complete denture users in the first six months.

Markovi? Dubravka

2002-01-01

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Effect of smoking on alveolar bone resorption  

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Full Text Available Introduction: Periodontal disease is one of the most common diseases in adults. Although the cause of periodontal disease is bacterial infection from the dental plaque, the level of destruction of periodontal tissues depends on risk factors, and smoking is one of the most important ones. Aim: The aim of the present study was to determine the level of alveolar bone resorption in smokers. Materials and Methods: Radiographic examination of all present teeth was conducted in 30 smokers (12 men and 18 women and 30 non-smokers (13 men and 17 women, control group, 20-60 years of age. Data on smoking habits, smoking period and the number of cigarettes a day were obtained using a questionnaire. The level of alveolar bone resorption was determined on retroalveolar X-rays, by measuring the distance from the amelo-cemental junction to the bone level on mesial and distal sides of each present tooth. Results: In smokers, significantly higher (p=0.00002 values of alveolar bone resorption (3.16 ± 2.07 mm were found compared to the control group (1.72 ± 1.02 mm. In people who had been smoking for more than 15 years, significantly greater bone resorption was observed compared to those smoking for 15 years or less (p=0.00028. The interceptive relationship showed that smokers were at 2.98x greater risk (95% CI 1.04- 8.52 for the mean value of alveolar bone resorption of > 2 mm compared to non-smokers. Conclusion: The present results have shown that smoking increases alveolar bone resorption and that the period of smoking affects the level of resorption.

Ra?unica Jelena

2008-01-01

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Effect of smoking on alveolar bone resorption  

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Introduction: Periodontal disease is one of the most common diseases in adults. Although the cause of periodontal disease is bacterial infection from the dental plaque, the level of destruction of periodontal tissues depends on risk factors, and smoking is one of the most important ones. Aim: The aim of the present study was to determine the level of alveolar bone resorption in smokers. Materials and Methods: Radiographic examination of all present teeth was conducted in 30 smokers (12 men an...

Ra?unica Jelena; Iveti? Vesna; Naumovi? Nada; ?uri? Milanko

2008-01-01

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A roentgenographic study of alveolar bone resorption using measurable grid  

International Nuclear Information System (INIS)

The author had performed the measurement of the various teeth regions on 200 cases of Full-mouth roentgenogram taken with the measurable Grid to detect the degree of alveolar bone resorption, aged from 20 to 60 years of Koreas, and to verify the effective result of measurable Grid as a new device which enables the observers to determine the correct length of images on the periapical standard film. The results were obtained as follows. 1. It was found that the degrees of alveolar bone resorption were different in the various teeth regions. 2. As a whole, alveolar bone resorption of anterior teeth regions was more severe than that of posterior teeth regions. 3. Alveolar bone resorption of mandibular region was more severe than that of maxillary region. 4. In sex difference, alveolar bone resorption of male is more severe than that of female, and it was increased with aging. 5. Measurable grid can be used as an adjunct of evaluation of alveolar bone resorption and of calculating the tooth length.

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An automatic early stage alveolar-bone-resorption evaluation method on digital dental panoramic radiographs  

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Periodontal disease is a kind of typical dental diseases, which affects many adults. The presence of alveolar bone resorption, which can be observed from dental panoramic radiographs, is one of the most important signs of the progression of periodontal disease. Automatically evaluating alveolar-bone resorption is of important clinic meaning in dental radiology. The purpose of this study was to propose a novel system for automated alveolar-bone-resorption evaluation from digital dental panoramic radiographs for the first time. The proposed system enables visualization and quantitative evaluation of alveolar bone resorption degree surrounding the teeth. It has the following procedures: (1) pre-processing for a test image; (2) detection of tooth root apices with Gabor filter and curve fitting for the root apex line; (3) detection of features related with alveolar bone by using image phase congruency map and template matching and curving fitting for the alveolar line; (4) detection of occlusion line with selected Gabor filter; (5) finally, evaluation of the quantitative alveolar-bone-resorption degree in the area surrounding teeth by simply computing the average ratio of the height of the alveolar bone and the height of the teeth. The proposed scheme was applied to 30 patient cases of digital panoramic radiographs, with alveolar bone resorption of different stages. Our initial trial on these test cases indicates that the quantitative evaluation results are correlated with the alveolar-boneresorption degree, although the performance still needs further improvement. Therefore it has potential clinical practicability.

Zhang, Min; Katsumata, Akitoshi; Muramatsu, Chisako; Hara, Takeshi; Suzuki, Hiroki; Fujita, Hiroshi

2014-03-01

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Bis-enoxacin blocks rat alveolar bone resorption from experimental periodontitis.  

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Periodontal diseases are multifactorial, caused by polymicrobial subgingival pathogens, including Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia. Chronic periodontal infection results in inflammation, destruction of connective tissues, periodontal ligament, and alveolar bone resorption, and ultimately tooth loss. Enoxacin and a bisphosphonate derivative of enoxacin (bis-enoxacin) inhibit osteoclast formation and bone resorption and also contain antibiotic properties. Our study proposes that enoxacin and/or bis-enoxacin may be useful in reducing alveolar bone resorption and possibly bacterial colonization. Rats were infected with 10(9) cells of polymicrobial inoculum consisting of P. gingivalis, T. denticola, and T. forsythia, as an oral lavage every other week for twelve weeks. Daily subcutaneous injections of enoxacin (5 mg/kg/day), bis-enoxacin (5, 25 mg/kg/day), alendronate (1, 10 mg/kg/day), or doxycycline (5 mg/day) were administered after 6 weeks of polymicrobial infection. Periodontal disease parameters, including bacterial colonization/infection, immune response, inflammation, alveolar bone resorption, and systemic spread, were assessed post-euthanasia. All three periodontal pathogens colonized the rat oral cavity during polymicrobial infection. Polymicrobial infection induced an increase in total alveolar bone resorption, intrabony defects, and gingival inflammation. Treatment with bis-enoxacin significantly decreased alveolar bone resorption more effectively than either alendronate or doxycycline. Histologic examination revealed that treatment with bis-enoxacin and enoxacin reduced gingival inflammation and decreased apical migration of junctional epithelium. These data support the hypothesis that bis-enoxacin and enoxacin may be useful for the treatment of periodontal disease. PMID:24638087

Rivera, Mercedes F; Chukkapalli, Sasanka S; Velsko, Irina M; Lee, Ju-Youn; Bhattacharyya, Indraneel; Dolce, Calogero; Toro, Edgardo J; Holliday, L Shannon; Kesavalu, Lakshmyya

2014-01-01

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Management of Compromised Vertical Alveolar Ridge using Distraction Osteogenesis  

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Full Text Available Deficient alveolar ridge is an often encountered problem which causes problem in providing prosthesis to patients. Acquired alveolar deficiencies are the result of tooth loss and associated periodontal disease, trauma or other pathology. This case report describes vertical mandibular alveolar ridge distraction achieved using Liebenger endosseous alveolar distractor device in a patient who had vertical ridge defect due to localized aggressive periodontitis leading to tooth loss. Total 5.6mm vertical distraction in mandibular alveolar ridge was achieved at 0.8mm per day in eight days. The advantage of this technique is that there is no need for bone harvesting hence it is not associated with donor site morbidity. Moreover gain of both soft tissue along with hard tissue is achieved.

Wg Cdr Parul Sharma

2011-12-01

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Quantification and visualization of alveolar bone resorption from 3D dental CT images  

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Purpose A computer aided diagnosis (CAD) system for quantifying and visualizing alveolar bone resorption caused by periodontitis was developed based on three-dimensional (3D) image processing of dental CT images. Methods The proposed system enables visualization and quantification of resorption of alveolar bone surrounding and between the roots of teeth. It has the following functions: (1) vertical measurement of the depth of resorption surrounding the tooth in 3D images, avoiding physical obstruction; (2) quantification of the amount of resorption in the furcation area; and (3) visualization of quantification results by pseudo-color maps, graphs, and motion pictures. The resorption measurement accuracy in the area surrounding teeth was evaluated by comparing with dentist's recognition on five real patient CT images, giving average absolute difference of 0.87 mm. An artificial image with mathematical truth was also used for measurement evaluation. Results The average absolute difference was 0.36 and 0.10 mm for surrounding and furcation areas, respectively. The system provides an intuitive presentation of the measurement results. Conclusion Computer aided diagnosis of 3D dental CT scans is feasible and the technique is a promising new tool for the quantitative evaluation of periodontal bone loss. (orig.)

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In-Vivo Effect of Andrographolide on Alveolar Bone Resorption Induced by Porphyromonas gingivalis and Its Relation with Antioxidant Enzymes  

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Alveolar bone resorption is one of the most important facts in denture construction. Porphyromonas gingivalis (Pg) causes alveolar bone resorption, and morphologic measurements are the most frequent methods to identify bone resorption in periodontal studies. This study has aimed at evaluating the effect of Andrographolide (AND) on alveolar bone resorption in rats induced by Pg. 24 healthy male Sprague Dawley rats were divided into four groups as follows: normal control group and three experimental groups challenged orally with Pg ATCC 33277 five times a week supplemented with 20?mg/kg and 10?mg/kg of AND for twelve weeks. Alveolar bones of the left and right sides of the mandible were assessed by a morphometric method. The bone level, that is, the distance from the alveolar bone crest to cementumenamel junction (CEJ), was measured using 6.1?:?1 zoom stereomicroscope and software. AND reduced the effect of Pg on alveolar bone resorption and decreased the serum levels of Hexanoyl-Lysine (HEL); furthermore the reduced glutathione/oxidised glutathione (GSH/GSSG) ratio in AND treated groups (10 and 20?mg/kg) significantly increased when compared with the Pg group (P < 0.05). We can conclude that AND suppresses alveolar bone resorption caused by Pg in rats. PMID:24151590

Al Batran, Rami; Al-Bayaty, Fouad H.; Al-Obaidi, Mazen M. Jamil

2013-01-01

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Macrophage depletion abates Porphyromonas gingivalis-induced alveolar bone resorption in mice.  

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The role of the macrophage in the immunopathology of periodontitis has not been well defined. In this study, we show that intraoral inoculation of mice with Porphyromonas gingivalis resulted in infection, alveolar bone resorption, and a significant increase in F4/80(+) macrophages in gingival and submandibular lymph node tissues. Macrophage depletion using clodronate-liposomes resulted in a significant reduction in F4/80(+) macrophage infiltration of gingival and submandibular lymph node tissues and significantly (p CD206(+)), were the dominant macrophage phenotype of the gingival infiltrate in response to P. gingivalis infection. P. gingivalis induced a significant (p < 0.01) increase in NO production and a small increase in urea concentration, as well as a significant increase in the secretion of IL-1?, IL-6, IL-10, IL-12 (p70), eotaxin, G-CSF, GM-CSF, macrophage chemoattractant protein-1, macrophage inflammatory protein-? and -?, and TNF-? in isolated murine macrophages. In conclusion, P. gingivalis infection induced infiltration of functional/inflammatory M1 macrophages into gingival tissue and alveolar bone resorption. Macrophage depletion reduced P. gingivalis infection and alveolar bone resorption by modulating the host immune response. PMID:25070844

Lam, Roselind S; O'Brien-Simpson, Neil M; Lenzo, Jason C; Holden, James A; Brammar, Gail C; Walsh, Katrina A; McNaughtan, Judith E; Rowler, Dennis K; Van Rooijen, Nico; Reynolds, Eric C

2014-09-01

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Effects of smoking on edentulous alveolar ridge mucosa  

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Full Text Available Introduction Tobacco use is an important risk factor for advanced histopathological findings on edentulous alveolar ridge mucosa. The aim of this study was to examine the effects of smoking on histopathological findings on edentulous alveolar ridge mucosa. Material and methods The experimental group consisted of 48 patients (29 smokers and 19 nonsmokers. The mean age of smokers was 42.6 and of nonsmokers 48.7 years. The anamnesis included the following data: age, sex, diseases and toxic habits-cigarette smoking. Biopsy samples were taken from the edentulous alveolar ridge mucosa without gross signs of symptoms. Results The mean number of cigarettes smoked per day was 11.5±7. The results of ?² test proved that there were no statistically significant differences (p>0.05 in histopathological findings on the alveolar ridge mucosa. The mean duration of smoking was 12.7± 5 years. Hyperkeratosis was established in 76.92% of smokers who smoked longer than 15 years. The mean-age at which smokers began smoking was 27.3±8 years and there were no statistically significant differences in histopathological findings on the alveolar ridge mucosa correlated with the beginning of smoking. Conclusion On the basis of our research we conclude that smokers who have been smoking for 15 years are at risk for developing histopathological changes of the alveolar ridge mucosa, but there were no statistically significant differences in histopathological findings on the alveolar ridge mucosa correlated with the number of cigarettes per day and the beginning of smoking. .

Markovi? Dubravka

2005-01-01

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Three-dimensional analysis of alveolar bone resorption by image processing of 3-D dental CT images  

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We have developed a novel system that provides total support for assessment of alveolar bone resorption, caused by periodontitis, based on three-dimensional (3-D) dental CT images. In spite of the difficulty in perceiving the complex 3-D shape of resorption, dentists assessing resorption location and severity have been relying on two-dimensional radiography and probing, which merely provides one-dimensional information (depth) about resorption shape. However, there has been little work on assisting assessment of the disease by 3-D image processing and visualization techniques. This work provides quantitative evaluation results and figures for our system that measures the three-dimensional shape and spread of resorption. It has the following functions: (1) measures the depth of resorption by virtually simulating probing in the 3-D CT images, taking advantage of image processing of not suffering obstruction by teeth on the inter-proximal sides and much smaller measurement intervals than the conventional examination; (2) visualizes the disposition of the depth by movies and graphs; (3) produces a quantitative index and intuitive visual representation of the spread of resorption in the inter-radicular region in terms of area; and (4) calculates the volume of resorption as another severity index in the inter-radicular region and the region outside it. Experimental results in two cases of 3-D dental CT images and a comparison of the results with the clinical examination results and experts' measurements of the corresponding patients confirmed that the proposed system gives satisfying results, including 0.1 to 0.6mm of resorption measurement (probing) error and fairly intuitive presentation of measurement and calculation results.

Nagao, Jiro; Kitasaka, Takayuki; Mori, Kensaku; Suenaga, Yasuhito; Yamada, Shohzoh; Naitoh, Munetaka

2006-03-01

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Resorption of monetite granules in alveolar bone defects in human patients.  

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Bone grafting is often required to restore mandibular or maxillary bone volume prior to prosthetic tooth root implantation. Preclinical animal models are often used to study the in vivo properties of new bone graft products designed for human use. Although animal studies may offer valuable data regarding bioperformance, materials do not necessarily perform the same in human patients. In this study we implanted bovine hydroxyapatite (BH), a widely used porous apatite granule, and dicalcium phosphate anhydrous (monetite) granules, bilaterally in human patients post extraction alveolar sockets. After six months, histomorphometrical analysis of the biopsies revealed that the amount of bone regenerated with monetite (59.5 +/- 13%) was significantly higher than that obtained with BH (33.1% +/- 4.9), while the amount of unresorbed graft was higher in the sockets treated with BH (37.8 +/- 6.1) than in those implanted with monetite (25.8 +/- 14.3). Resorption of calcium phosphate ceramics is discussed by applying the Hixon-Crowell dissolution model. PMID:20045555

Tamimi, Faleh; Torres, Jesus; Bassett, David; Barralet, Jake; Cabarcos, Enrique L

2010-04-01

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Single-stage implantation in the atrophic alveolar ridge of the mandible with the Norian skeletal repair system.  

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Dental implants have played a part in rehabilitation of the jaws for more than 40 years, but in some cases they alone are inadequate because of extreme alveolar resorption. Correction may necessitate a two-stage procedure with additional interventions. We have made a preliminary study of the use of the Norian skeletal repair system (SRS), a carbonated calcium phosphate bone cement used to augment the alveolar ridge as a single-stage procedure, with the placement of implants. Ten edentulous patients with insufficient vertical bone in the interforaminal area were treated. After a horizontal osteotomy and crestal mobilisation of the alveolar ridge, implants were placed through the crestal part and fixed in the basal part of the mandible. Norian SRS was used to fill the gap created. The prostheses were inserted 3 months later. Forty implants were inserted. The follow up period was 60 months, and no fractures or dislocations developed. One of the implants was lost and there was one wound dehiscence, but no surgical intervention or revision was necessary. Radiographs showed good consolidation of the bony structure in all cases. We have described a reliable, single-stage procedure for augmentation and implantation in a highly atrophic alveolar crest. A 98% survival is comparable with those of other techniques. Further clinical trials are necessary to replicate these promising results. PMID:21035238

Hölzle, Frank; Bauer, Florian; Kesting, Marco R; Mücke, Thomas; Deppe, Herbert; Wolff, Klaus-Dietrich; Swaid, Sami

2011-10-01

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Torus palatinus: a graft option for alveolar ridge reconstruction.  

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The reconstruction of the alveolar ridge with particulate bone collected from the torus palatinus is presented in this case report. Bone loss at the maxillary right permanent central incisor was rehabilitated with an implant-supported fixed prosthesis. The success of this approach demonstrates that the torus palatinus and torus mandibularis, found in approximately 20% and 27% of the population, respectively, are feasible options for bone regeneration, with several advantages compared to other sources of bone. Thus, surgeons should look for these bony growths, which result in surgery with less morbidity when included in the treatment plan. PMID:20386785

Moraes Junior, Edgard Franco; Damante, Carla Andreotti; Araujo, Sergio Ricardo

2010-06-01

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Aumento del reborde alveolar residual mediante técnica de rollo / Increase of residual alveolar ridge using roll technique  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish La pérdida dentaria, asociada a factores sistémicos, patológicos y traumáticos, promueve el proceso de reabsorción ósea de los rebordes residuales y genera problemas funcionales, como la falta de estabilidad y retención de las prótesis dentarias removibles, y disturbios estéticos y psicológicos. Est [...] os defectos varían en dependencia de la cantidad de pérdida ósea y de tejidos blandos que hayan alcanzado. En la actualidad son descritas diversas técnicas que permiten corregir estos defectos. Una de ellas es la técnica del rollo, la cual demuestra muy buenos resultados al aumentar el tamaño del reborde alveolar y disminuir los defectos estéticos que causa sobre todo en el sector anterior. El objetivo del presente artículo es describir el caso clínico de un paciente con pérdida ósea en el sector anterior, tipo III según Seibert, rehabilitado con prótesis parcial fija y sometido a un procedimiento quirúrgico con la técnica del rollo. Se alcanzaron los objetivos planteados y proporciona una mejoría estética así como una mejora en su calidad de vida. Se demostró que con esta técnica se obtienen resultados predecibles que devuelven la estética en zonas de alta exigencia por parte de los pacientes. Abstract in english Tooth loss associated with systemic factors, pathological and traumatic conditions, promotes the bone resorption of residual ridges, this, creates functional problems such as lack of stability and retention of removable dentures as well as aesthetic and psychological disturbances. These defects vary [...] depending on the amount of bone loss and soft tissue they reach. At present there are described various techniques that can correct these defects. One of these is the roll technique which shows very good results by increasing the size of the alveolar ridge and decrease aesthetic defects in the anterior area of the maxilla. The aim of this article is to describe a case of a patient with Seibert bone loss type III, rehabilitated with fixed partial denture after undergoing a surgical procedure with the roll technique achieving the stated objectives and providing aesthetic improvement to the patient and an improvement in their quality of life. It is shown that the technique can be achieved with predictable results that return aesthetics in areas of high demand from patients.

Miguel Ángel, Simancas Pallares; Alejandra del Carmen, Herrera Herrera; Luisa Leonor, Arévalo Tovar; Antonio José, Díaz Caballero; Farith Damián, González Martínez.

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Aumento del reborde alveolar residual mediante técnica de rollo Increase of residual alveolar ridge using roll technique  

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Full Text Available La pérdida dentaria, asociada a factores sistémicos, patológicos y traumáticos, promueve el proceso de reabsorción ósea de los rebordes residuales y genera problemas funcionales, como la falta de estabilidad y retención de las prótesis dentarias removibles, y disturbios estéticos y psicológicos. Estos defectos varían en dependencia de la cantidad de pérdida ósea y de tejidos blandos que hayan alcanzado. En la actualidad son descritas diversas técnicas que permiten corregir estos defectos. Una de ellas es la técnica del rollo, la cual demuestra muy buenos resultados al aumentar el tamaño del reborde alveolar y disminuir los defectos estéticos que causa sobre todo en el sector anterior. El objetivo del presente artículo es describir el caso clínico de un paciente con pérdida ósea en el sector anterior, tipo III según Seibert, rehabilitado con prótesis parcial fija y sometido a un procedimiento quirúrgico con la técnica del rollo. Se alcanzaron los objetivos planteados y proporciona una mejoría estética así como una mejora en su calidad de vida. Se demostró que con esta técnica se obtienen resultados predecibles que devuelven la estética en zonas de alta exigencia por parte de los pacientes.Tooth loss associated with systemic factors, pathological and traumatic conditions, promotes the bone resorption of residual ridges, this, creates functional problems such as lack of stability and retention of removable dentures as well as aesthetic and psychological disturbances. These defects vary depending on the amount of bone loss and soft tissue they reach. At present there are described various techniques that can correct these defects. One of these is the roll technique which shows very good results by increasing the size of the alveolar ridge and decrease aesthetic defects in the anterior area of the maxilla. The aim of this article is to describe a case of a patient with Seibert bone loss type III, rehabilitated with fixed partial denture after undergoing a surgical procedure with the roll technique achieving the stated objectives and providing aesthetic improvement to the patient and an improvement in their quality of life. It is shown that the technique can be achieved with predictable results that return aesthetics in areas of high demand from patients.

Miguel Ángel Simancas Pallares

2011-03-01

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Porphyromonas gingivalis GroEL Induces Osteoclastogenesis of Periodontal Ligament Cells and Enhances Alveolar Bone Resorption in Rats  

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Porphyromonas gingivalis is a major periodontal pathogen that contains a variety of virulence factors. The antibody titer to P. gingivalis GroEL, a homologue of HSP60, is significantly higher in periodontitis patients than in healthy control subjects, suggesting that P. gingivalis GroEL is a potential stimulator of periodontal disease. However, the specific role of GroEL in periodontal disease remains unclear. Here, we investigated the effect of P. gingivalis GroEL on human periodontal ligament (PDL) cells in vitro, as well as its effect on alveolar bone resorption in rats in vivo. First, we found that stimulation of PDL cells with recombinant GroEL increased the secretion of the bone resorption-associated cytokines interleukin (IL)-6 and IL-8, potentially via NF-?B activation. Furthermore, GroEL could effectively stimulate PDL cell migration, possibly through activation of integrin ?1 and ?2 mRNA expression as well as cytoskeletal reorganization. Additionally, GroEL may be involved in osteoclastogenesis via receptor activator of nuclear factor ?-B ligand (RANKL) activation and alkaline phosphatase (ALP) mRNA inhibition in PDL cells. Finally, we inoculated GroEL into rat gingiva, and the results of microcomputed tomography (micro-CT) and histomorphometric assays indicated that the administration of GroEL significantly increased inflammation and bone loss. In conclusion, P. gingivalis GroEL may act as a potent virulence factor, contributing to osteoclastogenesis of PDL cells and resulting in periodontal disease with alveolar bone resorption. PMID:25058444

Lin, Feng-Yen; Hsiao, Fung-Ping; Huang, Chun-Yao; Shih, Chun-Ming; Tsao, Nai-Wen; Tsai, Chien-Sung; Yang, Shue-Fen; Chang, Nen-Chung; Hung, Shan-Ling; Lin, Yi-Wen

2014-01-01

 
 
 
 
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Photoelastic stress analysis of endodontically treated teeth restored with different post systems: normal and alveolar bone resorption cases.  

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The present study examined the influence of different post materials and their lengths on the mechanical stress of endodontically treated incisor roots in two alveolar bone conditions. Two-dimensional photoelastic models were fabricated to simulate the endodontically treated maxillary central incisors restored with three kinds of posts materials (low Young's modulus glass fiber post, high Young's modulus glass fiber post, and prefabricated stainless steel post) and two post lengths (8 and 4 mm). Completed models were placed in a transmission polariscope and loaded with a static force of 150 N at 45° to the tooth axis. Photoelastic photographs and the magnitudes of fringe order revealed stress distribution in the root, and suggest that the glass fiber post with a low Young's modulus and long length can reduce the stress concentration both in normal and alveolar bone resorption conditions. PMID:22123004

Ma, Jinbao; Miura, Hiroyuki; Okada, Daizo; Yusa, Koichiro

2011-11-25

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Alveolar Ridge Augmentation with Titanium Mesh. A Retrospective Clinical Study  

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An adequate amount of bone all around the implant surface is essential in order to obtain long-term success of implant restoration. Several techniques have been described to augment alveolar bone volume in critical clinical situations, including guided bone regeneration, based on the use of barrier membranes to prevent ingrowth of the epithelial and gingival connective tissue cells. To achieve this goal, the use of barriers made of titanium micromesh has been advocated. A total of 13 patients were selected for alveolar ridge reconstruction treatment prior to implant placement. Each patient underwent a tridimensional bone augmentation by means of a Ti-mesh filled with intraoral autogenous bone mixed with deproteinized anorganic bovine bone in a 1:1 ratio. Implants were placed after a healing period of 6 months. Panoramic x-rays were performed after each surgical procedure and during the follow-up recalls. Software was used to measure the mesial and the distal peri-implant bone loss around each implant. The mean peri-implant bone loss was 1.743 mm on the mesial side and 1.913 mm on the distal side, from the top of the implant head to the first visible bone-implant contact, at a mean follow-up of 88 months. The use of Ti-mesh allows the regeneration of sufficient bone volume for ideal implant placement. The clinical advantages related to this technique include the possibility of correcting severe vertical atrophies associated with considerable reductions in width and the lack of major complications if soft-tissue dehiscence and mesh exposures do occur. PMID:25317209

Poli, Pier P; Beretta, Mario; Cicciu, Marco; Maiorana, Carlo

2014-01-01

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Alveolar ridge augmentation with titanium mesh. A retrospective clinical study.  

Science.gov (United States)

An adequate amount of bone all around the implant surface is essential in order to obtain long-term success of implant restoration. Several techniques have been described to augment alveolar bone volume in critical clinical situations, including guided bone regeneration, based on the use of barrier membranes to prevent ingrowth of the epithelial and gingival connective tissue cells. To achieve this goal, the use of barriers made of titanium micromesh has been advocated. A total of 13 patients were selected for alveolar ridge reconstruction treatment prior to implant placement. Each patient underwent a tridimensional bone augmentation by means of a Ti-mesh filled with intraoral autogenous bone mixed with deproteinized anorganic bovine bone in a 1:1 ratio. Implants were placed after a healing period of 6 months. Panoramic x-rays were performed after each surgical procedure and during the follow-up recalls. Software was used to measure the mesial and the distal peri-implant bone loss around each implant. The mean peri-implant bone loss was 1.743 mm on the mesial side and 1.913 mm on the distal side, from the top of the implant head to the first visible bone-implant contact, at a mean follow-up of 88 months. The use of Ti-mesh allows the regeneration of sufficient bone volume for ideal implant placement. The clinical advantages related to this technique include the possibility of correcting severe vertical atrophies associated with considerable reductions in width and the lack of major complications if soft-tissue dehiscence and mesh exposures do occur. PMID:25317209

Poli, Pier P; Beretta, Mario; Cicciù, Marco; Maiorana, Carlo

2014-01-01

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Distracción osteogénica del reborde alveolar: revisión de la literatura / Distraction osteogenesis of the alveolar ridge: a review of the literature  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish Uno de los principales problemas para la colocación de implantes dentales es la presencia de hueso insuficiente que impide que sean de una longitud y/o de un diámetro adecuados. Dentro de los métodos que se usan para el aumento del reborde alveolar se incluye tan solo desde hace una década la aplica [...] ción de los principios de distracción osteogénica (DO). Esta técnica se basa en la separación gradual de dos fragmentos de hueso perfectamente vascularizados, entre los que se forma un callo de distracción que progresivamente se transforma en hueso maduro. Un científico clave en el desarrollo de esta técnica fue el traumatólogo ruso Ilizarov. Esta revisión bibliográfica evalúa la metodología, el funcionamiento y las posibles aplicaciones de DO en el tratamiento de los defectos del reborde alveolar. Por sus cualidades demostradas, la DO podría sustituir el uso de injertos y regeneración ósea guiada para favorecer las relaciones esqueléticas de los rebordes alveolares. Abstract in english One of the principal problems in dental implantation is the lack of sufficient bone height or width. In the case of the alveolar ridge, a very effective technique for resolving this problem is distraction osteogenesis, introduced in this context about a decade ago. This technique is based on the gra [...] dual separation of a mobile but fully vascularized bone segment from the basal bone, leading to the formation of an intervening soft callus which gradually transforms to mature bone. A key researcher in the development of this technique was the Russian traumatologist Ilizarov. The present article reviews alveolar ridge distraction procedures and their clinical application. Alveolar ridge distraction may often be preferable to bone grafting or guided bone regeneration for increasing ridge height and width prior to implantation.

Nikola, Saulacic; Pilar, Gándara Vila; Manuel, Somoza Martín; Abel, García García.

2004-10-01

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Alveolar ridge preservation using xenogeneic collagen matrix and bone allograft.  

Science.gov (United States)

Alveolar ridge preservation (ARP) has been shown to prevent postextraction bone loss. The aim of this report is to highlight the clinical, radiographic, and histological outcomes following use of a bilayer xenogeneic collagen matrix (XCM) in combination with freeze-dried bone allograft (FDBA) for ARP. Nine patients were treated after extraction of 18 teeth. Following minimal flap elevation and atraumatic extraction, sockets were filled with FDBA. The XCM was adapted to cover the defect and 2-3?mm of adjacent bone and flaps were repositioned. Healing was uneventful in all cases, the XCM remained in place, and any matrix exposure was devoid of further complications. Exposed matrix portions were slowly vascularized and replaced by mature keratinized tissue within 2-3 months. Radiographic and clinical assessment indicated adequate volume of bone for implant placement, with all planned implants placed in acceptable positions. When fixed partial dentures were placed, restorations fulfilled aesthetic demands without requiring further augmentation procedures. Histological and immunohistochemical analysis from 9 sites (4 patients) indicated normal mucosa with complete incorporation of the matrix and absence of inflammatory response. The XCM + FDBA combination resulted in minimal complications and desirable soft and hard tissue therapeutic outcomes, suggesting the feasibility of this approach for ARP. PMID:25328523

Parashis, Andreas O; Kalaitzakis, Charalampos J; Tatakis, Dimitris N; Tosios, Konstantinos

2014-01-01

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Combined soft and hard tissue augmentation for a localized alveolar ridge defect.  

Science.gov (United States)

Ideal alveolar ridge width and height allows placement of a natural appearing pontic, which provides maintenance of a plaque-free environment. The contour of a partially edentulous ridge should be thoroughly evaluated before a fixed partial denture is undertaken. Localized alveolar ridge defect refers to a volumetric deficit of the limited extent of bone and soft-tissue within the alveolar process. These ridge defects can be corrected by hard tissue and/or soft-tissue augmentation. A 30-year-old male patient was referred to the Department of Periodontology for correction of Seibert's Class III ridge defect in the lower anterior region. Granulation tissue/connective tissue present at the base of the defect was removed after elevation of full thickness flap. MucoMatrixX, an animal derived, collagen based soft-tissue graft was sutured to the labial flap and bone graft was placed into the defect. If a soft-tissue graft material could be used to replace the palatal grafts, then all the possible complications associated with donor site would be eliminated and above all periodontal plastic surgery and ridge augmentation would be better accepted by patients. PMID:24403810

Rana, Ritu; Ramachandra, Srinivas Sulugodu; Lahori, Manesh; Singhal, Reetika; Jithendra, K D

2013-10-01

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Distracción osteogénica alveolar: una alternativa en la reconstrucción de rebordes alveolares atróficos: Descripción de 10 casos Alveolar distraction osteogenesis: an alternative in the reconstruction of atrophic alveolar ridges: Report of 10 cases  

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Full Text Available La distracción osteogénica alveolar (DOA es un método alternativo para la reconstrucción de rebordes alveolares atróficos que ofrece un resultado previsible y que disminuye los tiempo de espera entre la reconstrucción del reborde alveolar atrófico y la colocación de los implantes óseo-integrados, en comparación con los métodos tradicionalmente utilizados. Fueron atendidos 10 pacientes que presentaban deficiencia de reborde alveolar mandibular y/o maxilar por medio de distracción osteogénica, utilizando un dispositivo yuxtaoseo (Conexión Implant System® - SP-Brasil. Todos los pacientes fueron atendidos de forma ambulatoria, bajo anestesia local y sedación conciente, comenzando la activación del dispositivo a los 7 días posteriores a la instalación, con un patrón de activación de 1 mm diarios hasta alcanzar la altura ósea deseada. Posteriormente se aguardaron 10 semanas como parte del periodo de consolidación ósea y se realizo la colocación de los implantes oseointegrados y local y el retiro del dispositivo de distracción, pudiéndose comprobar clínica y radiográficamente la ganancia de la altura y volumen óseo necesario para la rehabilitación por medio de implantes.The alveolar distraction osteogenesis is an alternative method for the reconstruction of atrophic alveolar ridges with success, that decrease the time of wait between the reconstruction of the alveolar ridge and the placement of the osseointegrated implants in comparison with the traditionally used methods. 10 patients that presented deficiency of the alveolar ridge in the maxilla and/or mandible were assisted by means of distraction osteogenesis, using a juxtaosseous device (Conexion Implant System® - SP-Brazil. All the patients were assisted of form ambulatory, under local anesthesia and conscientious sedation, beginning the activation from the device 7 days later to the installation, with a pattern of activation 1 mm diary until reaching the wanted bony height. Later on 10 weeks like part of the period of bony consolidation were awaited and one carries out the placement of the osseointegraded implants and the retirement of the distraction device, being able to check clinic and radiographic the gain of the height and necessary bony volume for the rehabilitation by means of implants.

P.E. Maurette O’Brien

2004-02-01

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Chemical, physical, and histologic studies on four commercial apatites used for alveolar ridge augmentation  

DEFF Research Database (Denmark)

The purpose of this study was to evaluate four commercial apatite products. Subperiosteal alveolar ridge augmentation was performed on the maxilla of rats by implantation of granules of two dense products and of two porous products, and the tissue response was compared with the material characteristics obtained by chemical analysis and infrared spectrometry. None of the apatites caused osteoinduction or osteoconduction; fibrous encapsulation with multinuclear giant cells was observed around all four types. One of the apatites was fluorapatite and not hydroxylapatite, as claimed by the manufacturer. The tissue response to this implant material was dominated by multinuclear giant cells.

Pinholt, E M; Ruyter, I E

1992-01-01

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The effect of therapeutic radiation on canine alveolar ridges augmented with hydroxylapatite  

DEFF Research Database (Denmark)

The purpose of this investigation was to evaluate the effect of radiation on hydroxylapatite (HA) implanted subperiosteally for alveolar ridge augmentation in dogs. All bicuspids and molars were extracted from 16 dogs. After 6 weeks, nonporous HA granules were implanted subperiosteally on the alveolar ridge. Following 4 months of healing, 12 dogs (experimental group) underwent therapeutic radiation therapy (Co60, 4,000 rad [40 Gy]) to the head and neck region. Four dogs were not irradiated and served as controls. Four animals (three experimental and one control) were killed at 5,6,7, and 8 months after HA augmentation. Light microscopic evaluation showed that approximately 25% of HA granules were encased by bone while the others were surrounded by fibrous connective tissue. Dissolution of the HA was observed. Microparticles of HA were phagocytized as part of a granulomatous inflammatory reaction. This reaction decreased significantly as time elapsed after implantation. Osteoclastic activity was seen at the junction of HA and periosteum and as part of bone remodeling. Dissolution of the HA granules and the granulomatous inflammatory reaction were not significantly increased by therapeutic radiation. The radiation did not cause development of dehiscence or osteonecrosis.

Pinholt, E M; Kwon, P H

1992-01-01

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Alveolar ridge preservation using leukocyte and platelet-rich fibrin: a report of a case.  

Science.gov (United States)

In order for a dental implant to be restored optimally, it must be placed in an ideal anatomic position. However, this is not always possible, since physiological wound healing after tooth removal, often results in hard and soft tissue changes which ultimately compromises ideal implant placement. With the aim of minimising the need for tissue augmentation, several alveolar ridge preservation (ARP) techniques have been developed. These often require the use of grafting material and therefore increase the risk of disease transmission. Leukocyte and platelet-rich fibrin (L-PRF) is a newly developed platelet concentrate that is prepared from the patient's own blood. Clinical research has indicated that it improves wound healing and stimulates bone formation. We present a case where L-PRF was successfully used in an ARP procedure to facilitate implant placement in a compromised extraction socket. PMID:22567435

Peck, Mogammad Thabit; Marnewick, Johan; Stephen, Lawrence

2011-01-01

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Histopathologic findings in bone from edentulous alveolar ridges: a role in osteonecrosis of the jaws?  

Science.gov (United States)

Bisphosphonate-related osteonecrosis of the jaws (BONJ) is characterized by a breach in the oral mucosa with exposure of necrotic bone. Although bisphosphonates impact multiple biologic processes, including bone turnover and vascularity, factors contributing to the pathogenesis of BONJ remain poorly understood. In this retrospective analysis, the histopathologic findings from 154 alveolar bone specimens obtained during osteotomy preparation for dental implant placement were reviewed from 147 consecutively treated patients [male (79); female (68); Caucasian (141); African-American (6)]. The alveolar ridge sites had been edentulous for 1 year or longer. None of the patients in this study had a history of bisphosphonate therapy or clinical evidence of BONJ. Two pathologists, masked, using predetermined criteria, reviewed and substantiated the pathology reports provided by the licensed pathology service. In selected cases, special stains had been conducted to help establish the presence of bacteria. The histopathologic findings for the core specimens were as follows: 76 viable bone (49.4%); 54 nonviable bone (35.0%); and 24 osteomyelitis (15.6%). These histopathologic findings indicate that the edentulous jaw can contain regions of nonviable bone and microbial biofilm formation for 1 year or more after tooth extraction and mucosal healing. Regions of necrotic bone and subclinical infection may contribute to the development of untoward clinical events, such BONJ and early implant failure. PMID:20399289

Kassolis, James D; Scheper, Mark; Jham, Bruno; Reynolds, Mark A

2010-07-01

32

Reliability of pain tolerance threshold testing by applying an electrical current stimulus to the alveolar ridge.  

Science.gov (United States)

The purpose of this study was to assess the reliability of testing pain tolerance threshold (PTT) by applying an electrical current stimulus to the alveolar ridge. Twenty volunteers studying or working at the Nihon University School of Dentistry at Matsudo participated in this study. Participants were seated comfortably on a dental chair in a quiet room during testing. A single operator obtained mucosal PTT measurements around the right greater palatine foramen using a Neurometer CPT/C(®) device (Neurotron Inc., Baltimore, MD, USA) to deliver electrical stimulation at frequencies of 5, 250 and 2000 Hz. The participant released a button to automatically discontinue the stimulus when it could no longer be tolerated. Two types of factors were confirmed: the consistency of repeated measurements and a potential carry-over effect on PTTs. The consistency and carry-over effects of pain with regard to PTT measurements were analysed via Cronbach's coefficient ?. The Cronbach's coefficient ? of PTTs calculated more than 6 days of PTT testing at 5, 250 and 2000 Hz was 0.97, 0.95 and 0.97, respectively, suggesting that the consistency of the measurements was excellent. The Cronbach's coefficient ? calculated when the three frequencies of 5, 250 and 2000 Hz were applied in different orders was 0.91, 0.87 and 0.90, respectively, suggesting no carry-over effect. In conclusion, the measurement of PTTs at the alveolar ridge as assessed by applying an electrical current stimulus with an electro-diagnostic device exhibited excellent reliability, and thus, it constitutes a widely available option for PTT measurement in the clinical setting. PMID:24814257

Nakashima, Y; Kimoto, S; Kawai, Y

2014-08-01

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Alveolar ridge reconstruction with titanium meshes: A systematic review of the literature.  

Science.gov (United States)

Alveolar bone regeneration by means of titanium meshes is a widespread procedure, however to date, only few relevant studies were reported in literature concerning this technique. Consequently, the aim of the present systematic review was to analyze the reliability of the titanium mesh as a barrier, in conjunction with horizontal and vertical ridge reconstruction for implant placement purposes. A total of 17 articles complying with the inclusion and exclusion criteria were reviewed. Three outcome variables were defined: a) horizontal and vertical bone regeneration obtained, b) complication rate, defined as the percentage of membrane exposures and c) evaluation of implant survival, success and failure rate.In regards to the vertical regeneration the mean was 4.91 mm (range: 2.56 - 8.6), while a mean of 4.36 mm (range: 3.75 - 5.65) was calculated for horizontal reconstruction.Considering the exposure rate, a mean of 16.1% was found, nevertheless, implant placement were placed in almost all of the sites. A mean success rate of 89,9%, a mean survival rate of 100% and a failure rate of 0% emerged from the data evaluation. A meta-analysis could not be performed due to the heterogeneity of the data, however the final results were comparable with those reported in case of bone regeneration obtained through other types of non-resorbable membranes. An advantage in favour of the titanium mesh was found in terms of bone loss after exposure, as implant placement was not jeopardized in almost all of the cases. It could be deduced that titanium meshesrepresented a reliable solution for alveolar ridge reconstruction. The clinical studies currently available in literature have shown the predictability of this technique in both lateral and vertical bone regeneration. PMID:25350597

Rasia-Dal Polo, M; Poli, P-P; Rancitelli, D; Beretta, M; Maiorana, C

2014-01-01

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Prosthetic Management of an Extensive Maxillary Alveolar Resorption with an Implant-supported Restoration: a Technical Report  

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Full Text Available Despite the recent developments in peri-implant surgical regenerative procedures, re-establishing the hard and soft tissue contour is still a challenge in cases with severe ridge deficiency. It becomes more difficult when incorrectly placed implants cause screw connections to come out onto the labial surfaces of the teeth. A two-part maxillary implant supported fixed restoration was constructed. The first part was consisted of a screw retained sub-structure that replaced gingival portions of the deficient maxilla and the second part was a cement retained super-structure that reconstructed the anatomical crowns of the lost teeth. In this way awkwardly placed implants did not interfere with the desired esthetic result. Another great advantage was that the alterations or repairs on cemented crowns can easily be carried out without compromising the entire construction.

Fariborz Saadat

2013-01-01

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Photoelastic Stress Analysis Surrounding Implant-Supported Prosthesis and Alveolar Ridge on Mandibular Overdentures  

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Full Text Available The purpose of this research was to evaluate the maximum stress around osseointegrated implants and alveolar ridge, in a mandible with left partial resection through a photoelastic mandibular model. The first group consisted of two implants: traditional model (T, implants placed in the position of both canines; fulcrum model (F, implants placed in the position of left canine CL and right lateral incisor LiR. Both models linked through a bar and clips. The second group was consisted of three implants, with implants placed in the position of both canines (CR and CL and the right lateral incisor (LiR, which composed four groups: (1 model with 3 “O” rings, (2 model 2 ERAs, bar with clips, (3 model 2 ERAs bar without clips; (4 model “O” ring bar and ERA. An axial and an oblique load of 6.8?kgf was applied on a overdenture at the 1st Pm, 2nd Pm, and 1st M. Results showed that the area around the left canine (CL was practically free of stress; the left lateral incisor (LiL developed only small tensions, and low stress in all the other cases; the right canine tooth suffered the largest concentrations of stress, mainly with the ERA retention mechanism.

Rafael Yagüe Ballester

2010-01-01

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Efficacy of Enamel Matrix Derivative on Alveolar Ridge Augmentation by Distraction Osteogenesis  

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Full Text Available Distraction osteogenesis (DO is a surgical-orthopedic technique for lengthening a bone by separating or distracting a fractured callus. The aim of this study was to observe the effects of an enamel matrix derivative (EMD on bone repair and regeneration after DO on a canine mandible. Ten adult beagle dogs were used in this study. Their right and left mandibles were compared as the test and control groups, respectively. The distraction was undertaken at a rate of 1 mm per day for 10 consecutive days to yield 10 mm lengthening of the mandibular corpus. The EMD was treated into the test group at the site of the lengthened bone. At 0, 1, 3, 6 and 9 weeks after EMD treatment, the bone mineral density (BMD at the site of the lengthened bone was measured using quantitative computed tomography. BMD in the tested group was higher during consolidation period than in the control. The difference in the BMD of 1 and 3 weeks after EMD treatment was significant (p < 0.05. In histological findings, new bone formation in the test group was denser than the control group. These results suggest that the application of an EMD during DO is suitable method for alveolar ridge augmentation in dogs.

J.M. Kim, J.H. Kim, T.S. Han, G. Kim, S.S. Kang1 and S.H. Choi*

2011-04-01

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Anthropometric Measurements in Toothed and Toothless Maxillaries and its Consequences in Human Alveolar Bone Resorption / Mediciones Antropométricas en Maxilares con y sin Dientes de Humanos y sus Consecuencias en la Reabsorción Ósea Alveolar  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in spanish Este estudio propuso medir y comparar las medidas antropométricas entre los maxilares con y sin dientes. Fueron utilizados 26 cráneos humanos, 13 maxilares con dientes y 13 sin dientes. Las mediciones fueron realizadas a ambos lados por dos evaluadores entre las distancias del reborde alveolar (RA): [...] a la espina nasal anterior (ENA), al canal incisivo (CI) y a lo foraámenes palatinos mayor (FPMA) y menor (FPME). Los datos mostraron que la media de las mediciones fueron proporcionalmente mayores en las maxilas con dientes, para todas las mediciones en cualquiera de los evaluadores. El RA-ENA (p = 0,001), AR-CI (p = 0,006), RA-APMA derecho (p = 0,001) y RA-APMA izquierdo (p Abstract in english This study proposes to measure and compare anthropometric measurements between toothed and toothless maxillas. 26 human skulls were used with: 13 toothed and 13 toothless maxillas. The measurements were made between the distances of the alveolar ridge (AR): the anterior nasal spine (ANS), to the inc [...] isive foramen (FI) and the palatine foramen, greater (FPMA) and lower (FPME) on both sides by two evaluators. The data obtained showed that the average of the measurements were correspondingly higher in toothed maxillas than in toothless, for all measurements in any one of the evaluators. The AR-ANS (p = 0.001), IF-AR (p = 0.006), AR-FPMA right (p = 0.001) and AR-FPMA left (p

Jaciel Benedito, de Oliveira; Andrelle Nayara Cavalcanti Lima de, Almeida; Carla Cabral dos Santos Accioly, Lins; Adelmar Afonso de Amorim, Júnior; Zélia Albuquerque, Seixas.

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Carcinoma de células escamosas em rebordo alveolar inferior: diagnóstico e tratamento odontológico de suporte / Squamous cell carcinoma in lower alveolar ridge: diagnosis and odontologic support treatment  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O carcinoma epidermóide é a neoplasia maligna mais comum de cavidade oral e estruturas adjacentes. Apresenta maior incidência no gênero masculino, após a quarta década de vida, e tem como principais fatores etiológicos os usos crônicos de tabaco e álcool. Neste trabalho é relatado um caso de carcino [...] ma de células escamosas do rebordo alveolar inferior, que não é uma região preferencial para esse tipo de patologia. Também é discutida a importância do cirurgião-dentista na equipe de profissionais que assiste esses pacientes, tanto no diagnóstico precoce quanto no manejo das alterações estomatológicas advindas da terapia antineoplásica. Abstract in english Squamous cell carcinoma is the most common malignant neoplasm in oral cavity and adjacent structures. Its prevalence is higher in males, after the fourth decade, and the main etiologic associated factors are smoking and alcohol. This study reports a case of squamous cell carcinoma arising from the l [...] ower alveolar ridge, a non-preferential site for this pathology. It also discusses the importance of the dentist in the team of professionals assisting these patients, in early diagnosis and treatment of the stomatological alterations due to antineoplastic therapy.

Filipe Ivan, Daniel; Rodrigo, Granato; Liliane Janete, Grando; Sônia Maria Lückmann, Fabro.

2006-08-01

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Carcinoma de células escamosas em rebordo alveolar inferior: diagnóstico e tratamento odontológico de suporte Squamous cell carcinoma in lower alveolar ridge: diagnosis and odontologic support treatment  

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Full Text Available O carcinoma epidermóide é a neoplasia maligna mais comum de cavidade oral e estruturas adjacentes. Apresenta maior incidência no gênero masculino, após a quarta década de vida, e tem como principais fatores etiológicos os usos crônicos de tabaco e álcool. Neste trabalho é relatado um caso de carcinoma de células escamosas do rebordo alveolar inferior, que não é uma região preferencial para esse tipo de patologia. Também é discutida a importância do cirurgião-dentista na equipe de profissionais que assiste esses pacientes, tanto no diagnóstico precoce quanto no manejo das alterações estomatológicas advindas da terapia antineoplásica.Squamous cell carcinoma is the most common malignant neoplasm in oral cavity and adjacent structures. Its prevalence is higher in males, after the fourth decade, and the main etiologic associated factors are smoking and alcohol. This study reports a case of squamous cell carcinoma arising from the lower alveolar ridge, a non-preferential site for this pathology. It also discusses the importance of the dentist in the team of professionals assisting these patients, in early diagnosis and treatment of the stomatological alterations due to antineoplastic therapy.

Filipe Ivan Daniel

2006-08-01

40

Orthopantomographic study of the alveolar bone level on periodontal disease  

International Nuclear Information System (INIS)

The author had measured the alveolar bone level of periodontal disease on 50 cases of orthopantomogram to detect the degree of alveolar bone resorption of both sexes of Korean. The results were obtained as follows; 1. Alveolar bone resorption of mesial and distal portion was similar in same patient. 2. The order of alveolar bone resorption was mandibular anterior region, posterior region, canine and premolar region of both jaws. 3. The degree of alveolar bone destruction was severe in shorter root length than longer one. 4. The degree of alveolar bone resorption was severe in fourth decades.

 
 
 
 
41

Multiple congenital epulis in alveolar ridges of maxilla and mandible in a newborn: a rare case report.  

Science.gov (United States)

Congenital granular cell lesion (CGCL) or congenital epulis is an uncommon benign of the oral cavity tumor appearing at birth with typical clinical and pathologic features. It predominately affects females, mainly on the anterior maxillary alveolar ridge, and occurs usually as a single mass, although sometimes as multiple. The left side incisor area is the most common site. The etiology and histogenesis of the lesion remain obscure. Though it is a benign lesion, the tumor may cause feeding and respiratory problems if there are too large or multiple tumors. We report a case of a three-day-old, female newborn, who was referred to our hospital with multiple congenital oral swellings arising from the maxilla and mandible. The tumors caused a feeding problem and, hence, they were resected by surgical excision under general anesthesia. PMID:24808964

Saki, Nader; Araghi, Somayeh

2014-01-01

42

Clinical and histologic evaluation of fresh frozen human bone grafts for horizontal reconstruction of maxillary alveolar ridges.  

Science.gov (United States)

The aims of the present study were to clinically and histologically evaluate human fresh frozen bone (FFB) grafts used to treat severe maxillary horizontal defects prior to dental implant placement. Ten patients were treated with FFB onlay grafts. Measurements using computed tomography scans were recorded preoperatively and at 5 months. Six core biopsies were retrieved and processed for light microscopy. At baseline, thickness of the maxillary alveolar ridge measured 2.3 ± 0.4 mm; it measured 6.8 ± 0.5 mm after reconstruction. All implants were successful after 24 months. Histologic results showed that FFB blocks and new bone were integrated perfectly. Histomorphometry revealed a mean percentage of bone of 57.5% ± 24.7%. PMID:21845248

Orsini, Giovanna; Stacchi, Claudio; Visintini, Erika; Di Iorio, Donato; Putignano, Angelo; Breschi, Lorenzo; Di Lenarda, Roberto

2011-01-01

43

Pressure produced on the residual maxillary alveolar ridge by different impression materials and tray design: an in vivo study.  

Science.gov (United States)

Increased ridge resorption may occur due to inappropriate pressure applied during final impression making phase of complete denture fabrication. This study was done to evaluate the pressure applied on the residual ridge while making impressions with two tray designs (with and without spacer) using, zinc oxide eugenol and light body polyvinyl siloxane impression material. Five edentulous subjects were randomly selected. For each of the five subjects four maxillary final impressions were made and were labelled as, Group A-Impression made with tray without spacer using zinc oxide eugenol impression, Group B-Impression made with tray with spacer using zinc oxide eugenol impression material, Group C-Impression made with tray without spacer using light body polyvinyl siloxane impression material, Group D-Impression made with tray with spacer using light body polyvinyl siloxane impression material. During the impression procedure a closed hydraulic system was used to remotely measure the pressures produced in three areas. The pressure produced were calibrated according to the micro strain record. Statistical comparisons of readings were done using t test and ANOVA. The acquired data revealed that ZOE produced an average pressures value of 26.534 and 72.05 microstrain, while light body PVS produced 11.430 and 37.584 microstrain value with and without spacer respectively. Significantly high values were recorded on the vault of the palate when using trays without spacer. The use of light body polyvinyl siloxane and zinc oxide eugenol impression material showed insignificant difference. Within the limitations of this study, tray design has a significantly effected on the pressures produced, while the impression materials does not have any significant difference. PMID:24431783

Reddy, Subash M; Mohan, Chenthil Arun; Vijitha, D; Balasubramanian, R; Satish, A; Kumar, Mahendira

2013-12-01

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Fate of autologous and fresh-frozen allogeneic block bone grafts used for ridge augmentation. A CBCT-based analysis  

DEFF Research Database (Denmark)

OBJECTIVES: To evaluate dimensional changes in autologous (AT) and fresh-frozen allogeneic (AL) block bone grafts 6 months after alveolar ridge augmentation. MATERIAL AND METHODS: Twenty-six partially or totally edentulous patients treated either with fresh-frozen AL bone or AT bone onlay block grafts prior to implant placement (13 patients in each group), were included in this analysis. Patients received CBCT (i-CAT Classic) examinations prior to surgery and 14 days and 6 months after grafting. Differences in alveolar ridge area among the various observation times were evaluated by planimetric measurements on two-dimensional CBCT images of the grafted regions. Nineteen grafted blocks from each group were evaluated. RESULTS: Significant increase in alveolar ridge dimensions, allowing implant placement, was obtained with both types of grafts 6 months after grafting; no significant differences in alveolar ridge area were observed between the groups at the various observation times. However, graft resorption in the AL group was significantly larger compared to that in the AT group at 6 months. CONCLUSIONS: Larger bone graft resorption was seen in patients treated with fresh-frozen AL bone than in those treated with AT bone 6 months following alveolar ridge augmentation.

Spin-Neto, Rubens; Stavropoulos, Andreas

2013-01-01

45

Evaluación radiográfica de aumentos de rebordes alveolares con injertos aloplásticos de hidroxiapatita no reabsorbible: seguimiento a nueve meses Radiographic evaluation of alveolar ridge augmentation with non resorbable hydroxyapatite alloplastic grafts: nine months follow up  

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Full Text Available INTRODUCCIÓN: el objetivo fue determinar radiográficamente el porcentaje de estabilidad de la altura del reborde alveolar del maxilar superior e inferior en pacientes sometidos a cirugía preprotésica de aumento de reborde con implante de HA no reabsorbible. MÉTODOS: el estudio se realizó en quince pacientes, en quienes se determinaron mediciones reproducibles. Para el maxilar superior: (A desde espina nasal anterior; (B derecha-izquierda desde el borde más inferior de las fosas nasales; (C derecha- izquierda desde el borde más inferior de la órbita. Para el maxilar inferior: (E desde el borde inferior de la mandíbula y pasando por la sínfisis; (F derecha-izquierda pasando por el agujero mentoniano; (G derecha-izquierda pasando 5 mm. atrás del agujero mentoniano; (H derecha-izquierda pasando 10 mm posterior al agujero mentoniano. Todas las mediciones se realizaron en el prequirúrgico, en el posquirúrgico inmediato, y a los nueve meses. RESULTADOS: se promediaron los diferentes puntos del maxilar superior (PPMXS y se observó una pérdida de altura entre el 6,29 y un 33,6% con promedio del 17,36 %. En el maxilar inferior (PPMXI se observó una variación desde ganancia del 6,31% hasta una disminución del 18,87%, con promedio del 2,54%. CONCLUSIONES: el implante de HA permite restablecer adecuada altura del reborde alveolar. La altura del reborde alveolar obtenida inicialmente presenta un porcentaje de disminución de su altura en el maxilar superior del 17,36%, y en el maxilar inferior del 2,54 durante el seguimiento a nueve meses.INTRODUCTION: the purpose of this study was to determine radiographically the percentage of stability of alveolar ridge height in the maxilla and the mandible in patients subjected to pre prosthetic surgery of ridge augmentation with non resorbable HA implants. METHODS: the study was performed in 15 patients in whom reproducible measurements were taken. For the maxilla: (A From Anterior Nasal Spine; (B right and left from the lowest border of the nasal fossae; (C right and left from the lowest border of the orbit. For the mandible: (E from the lowest border of the mandible passing through symphysis; (F right and left passing through the mental foramen; (G right and left passing 5 mm posterior to the mental foramen; (H right and left passing 10 mm posterior to mental foramen. All measurements were performed before surgery, immediately after and, nine months after surgery. RESULTS: the different points of the maxilla were averaged (PPMXS and a height loss between 6.29% and 33.6% was observed, with an average of 17.36%. For the mandible (PPMXL variations ranging from 6.31% of augmentation to 18.8% loss were observed, with an average of 2.54%. CONCLUSIONS: HA implants allow reestablishment of adequate alveolar ridge height. The alveolar ridge height initially obtained presents a decrease percentage in height for the maxilla of 17.36% and 2.54% for the mandible after nine months follow up.

Félix Antonio Gil Cárdenas

2008-12-01

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Evaluación clínica y radiográfica de la técnica de distracción osteogénica en la reconstrucción de rebordes alveolares atróficos en la región anterior del maxilar superior A clinical and radiographic evaluation of the distraction osteogenesis technique for the reconstruction of atrophic alveolar ridges in the anterior region of the upper maxilla  

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Full Text Available Este estudio tiene como objetivo evaluar clínica y radiográficamente la técnica de distracción osteogénica alveolar en la región anterior del maxilar superior y las posibles complicaciones que pueden aparecer durante el tratamiento. Fueron evaluados 15 pacientes, sometidos a reconstrucción alveolar del maxilar superior en la región anterior con distracción osteogénica, usando un distractor yuxtaóseo. Del total de 15 pacientes encontramos que 13 pacientes (86,6% obtuvieron un éxito total de la técnica, obteniendo una ganancia ósea real media de 7,04 mm; en 1 paciente (6,66% fue parcial (2,62 mm y en 1 paciente (6,66% se evidenció un fracaso en la técnica, al alcanzar solo 0,76 mm debido a problemas en la activación del distractor. En cuanto a las complicaciones surgidas durante el tratamiento fueron divididas en complicaciones menores, toda aquella que no interfirió en el éxito del tratamiento, y que estuvieron presentes en 8 pacientes (53,33%, y complicaciones mayores aquellas que no permitieron la rehabilitación con implantes, y que fue encontrado solo en 1 paciente (6,66%. La técnica de distracción osteogénica alveolar, demostró ser eficaz en la reconstrucción de rebordes alveolares atróficos con un éxito de 93,33%, presentado pequeñas complicaciones que pueden ser solventadas por medio de un seguimiento por parte del profesional.This study evaluates clinically and radiographically the distraction osteogenesis technique for the reconstruction of atrophic alveolar ridges in the anterior maxilla region, and the possible complications that arise during treatment. Fifteen patients were evaluated, clinically and radiographically, that had been treated with alveolar distraction osteogenesis in the anterior region, using a juxta-osseous distractor. In 13 patients (86.6% the technique was completely successful, there being an effective bone gain of 7,04 mm. In 1 patient (6.66% this was partial (2.62 mm and in 1 patient (6.66% the technique failed, as there was a gain of just 0,76 mm because of problems during the activation. The complications arising during the alveolar distraction osteogenesis were divided into minor complications that did not compromise the success of the technique, and which were found in 8 patients (53.33%, and major complications that did not permit rehabilitation, which were found in 1 patient (6.66%. The alveolar distraction osteogenesis technique proved to be an effective technique for the reconstruction of atrophic alveolar ridges with a success rate of 93.33%. There were minor complications but the surgeon intervened in time and these were solved.

M.E. Allais de Maurette

2005-06-01

47

[External root resorption].  

Science.gov (United States)

Root resorption may be a physiological (resorption of deciduous teeth) or a pathological process (resorption of permanent teeth). In the latter case an external and an internal form of resorption can be distinguished. Root resorption may occur on one tooth or on several teeth within a dentition and it may be caused by trauma, periodontitis, orthodontic treatment, internal bleaching, cysts, tumors, or by stimuli from a necrotic dental pulp. Current knowledge concerning the pathogenesis of root resorption and therapeutic approaches are presented. For cervical resorption, it is assumed that the stimulus for the resorbing cells originates from the bacteria within the gingival sulcus and along the affected root surface. The case presented here was initially diagnosed as chronic periodontitis of medium severity. Scaling and root planing were performed resulting in a significant improvement of the periodontal status. Two years later, following a period of irregular recall visits, the patient presented with large areas of cervical resorption on teeth 36 and 37 which made it impossible to preserve these teeth. After another six months, teeth 34 and 35 showed deep destruction caused by external root resorption, mandating the extraction of these teeth as well. Fourteen months later, external root resorptions were evident on teeth 32 and 33, and at the same time, a recurrence of the chronic periodontitis was noted. Periodontal therapy was performed under a systemic antibiotic regime. It was possible to preserve teeth 32 and 33 through surgical crown lengthening procedures. No additional resorption has been observed ever since. PMID:16610460

Rathe, Florian; Nölken, Robert; Deimling, Daniela; Ratka-Krüger, Petra

2006-01-01

48

Frequency of the external resorptions of root apex  

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Full Text Available Root resorptions present a significant problem in endodontic therapy of the affected teeth and in dentistry in general. The objective of this study was to analyze, based on epidemiological and statistical research, the frequency of clinical incidence of pathological root resorptions in everyday practice related to localization, type of tooth, age and sex of patients. Radiographie documentation of patients treated from 1997 till 2002 at the Department of Conservative Dentistry and Endodontics, Faculty of Stomatology in Belgrade, was used as baseline for this study. Retroalveolar radiographs of teeth with visible signs of resorptions were singled out from 15654 patients' clinical records used for this study. The external resorptions were shown as radiolucent areas localized on various outer root surfaces, followed by significant or less significant resorption of lamina dura and alveolar bone. Out of all teeth analyzed in this study, 594 (3.79% showed some kind of resorption. The external resorptions were found to be more present in the upper jaw (55.10% and molars (50.30% than in the lower jaw (44.90% and single root teeth (49.70%, but in both cases without significant statistical differences. The most frequent localization of resorptions was root apex (82.44%. In regard to age, the most frequent resorptions were recorded in patients aged between 21 and 30 years (28.40%, and the lowest incidence was found in the youngest population (5.51%. The results also showed that resorptions were more frequent among the female population (59.04% than among the male population (40.96%. Based on these results, we may conclude that the external root resorptions are not a frequent clinical phenomenon. Proper and early diagnostics of such tissue pathology is one of the basic prerequisites for successful endodontic therapy of the affected root.

Opa?i?-Gali? Vanja

2004-01-01

49

Odontoclastic resorptive lesions in a dog.  

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We found odontoclastic resorptive lesions on premolars and molars in a 4- year-old miniature dachshund. The teeth had been extracted because the dentin was resorbed. In some teeth, the roots had been replaced by hard tissue, and so we amputated the crowns and curetted roots and alveolar bone. Histopathological examination revealed that the dentin was resorbed by odontoclasts and was replaced with bony tissue. Ten months later we found resorptive lesions in other teeth, and we treated them along with the first treatment. At the time of writing, since this is the first report of a dog with the same lesion in other teeth after the first treatment, we hope to establish better treatment and prevention methods. PMID:18250581

Yoshikawa, Hiroto; Watanabe, Kazuhiro; Ozawa, Tsuyoshi

2008-01-01

50

Alveolar distraction osteogenesis – Crestal widening by distraction osteogenesis  

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Full Text Available Following tooth extraction, resorption of the residual ridges occurs in both the vertical and the horizontal directions. Most of this resorption occurs within the first 6 months after tooth extraction. To correc tthis vertical/ horizontal/ dual situation, several surgical approaches have been proposed: autogenous bone grafts, guided bone regeneration, and alveolar distraction osteogenesis (ADO. In recent years, ADO has gained an ongoing popularity ,especially in view of its numerous advantages, mostimportant among them being the shortening of treatment periods and earlier dental implant placement. In cases in which there is sufficient vertical height but not enough bucco-ligual width to accommodate an implant, crestal width has to be built. Crestal widening by distraction osteogenesis is the preferred technique in suchcases. In this study a new type of crest widener, the"Laster" Crest Widening Distractor, is presented, reporting two cases where crest widening by distraction was chosen as the preferred treatment plan. Finally the main advantages and disadvantages of the new crest widening distractor are discussed, helping thus the clinician to make up his mind about this new promising device and surgical technique.

Zvi Laster

2010-04-01

51

Resorption heat pump  

Energy Technology Data Exchange (ETDEWEB)

Resorption processes are based on at least two solid-sorption reactors application. The most favorable situation for the resorption heat pumps is the case, when the presence of a liquid phase is impossible. From simple case-two reactors with two salts to complicated system with two salts + active carbon fiber (fabric) and two branch of the heat pump acting out of phase to produce heat and cold simultaneously, this is the topic of this research program. (author)

Vasiliev, L.L.; Mishkinis, D.A.; Antukh, A.A.; Kulakov, A.G. [National Academy of Sciences, Minsk (Russian Federation). Luikov Heat and Mass Transfer Institute

2004-09-01

52

Accuracy of vertical bitewing and bisect periapical radiography techniques in anterior mandibular teeth interdental bone resorption  

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Full Text Available Introduction: Alveolar bone level is changed due to the balance between bone formation and resorption. Radiographic examination has an important role in the diagnosis and treatment of periodontal diseases. This study was performed to compare the accuracy of vertical bitewing and periapical radiography in anterior mandibular teeth interdental bone resorption using grid sheet.Materials and Methods: A total of 20 patients who all needed periodontal surgery on their anterior mandibular region were included. Before surgery, using grid sheet, 3 periapical radiographs and 3 vertical bitewing radiographs were taken from the anterior mandibular region, and the distance between CEJ and the crest of alveolar bone were measured on the scaled radiographs. During periodontal surgery the real amount of bone resorption was measured via Williams probe. The collected data were then analyzed by paired-t-test.Results: The mean of alveolar bone resorption on vertical bitewing radiography was 3.88 ± 1.06 and 3.97 ± 0.97 for mandibular incisors and mandibular canines respectively. On periapical radiography however, the same value was 3.80 ± 0.75 for mandibular incisors, and 3.90 ± 1.11 for mandibular canines. Applying Williams probe during surgery, the mean value of real alveolar bone resorption was found to be 3.20 ± 1.20 for mandibular incisors, and 3.18 ± 1.03 for mandibular canines.Conclusion: Based on the findings, there were significant differences between the findings on periapical and vertical bitewing radiographs with the real amount of bone resorption recorded during surgery. However, the difference between the accuracy of bite wing and periapical radiography in measuring the amount of alveolar bone resorption in anterior mandibular region was not significant.

Mohamad Shah Abouei

2009-01-01

53

A 5- Year Comparison of Marginal Bone Level Following Immediate Loading of Single-Tooth Implants Placed in Healed Alveolar Ridges and Extraction Sockets in the Maxilla.  

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Full Text Available AbstractPurpose: The aim of present investigation was to evaluate marginal bone level after 5-year follow-up of implants placed in healed ridges and fresh extraction sockets in maxilla with immediate loading protocol.Materials and Methods: Thirty-six patients in need of a single tooth replacement in the anterior maxilla received 42 Astra Tech implants (Astra Tech Implant system™, Dentsply Implants, Mölndal, Sweden. Implants were placed in healed ridges (group I or immediately into extraction sockets (group II. Implants were restored and placed into functional loading immediately by using a prefabricated abutment. Marginal bone level relative to the implant reference point was recorded at implant placement, crown cementation, 12, 36 and 60 months following loading using intra-oral radiographs. Measurements were made on the mesial and distal sides of each implantResults: Overall, two implants were lost from the group II, before final crown cementation: they were excluded from the study and all remaining implants osseointegrated successfully after 5 years of functional loading. The mean change in marginal bone loss after implant placement was 0.267±0.161 for one year, and 0.265±0.171 for three years and 0.213±0.185 for five years in extraction sockets and was 0.266±0.176 for one year and 0.219±0.175 for three years and 0.194±0.172 for five years in healed ridges group. Significant reduction of marginal bone loss was more pronounced in implants inserted in healed ridges (P

AntoineNicolasBerberi

2014-01-01

54

The efficacy of hydrothermally obtained carbonated hydroxyapatite in healing alveolar bone defects in rats with or without corticosteroid treatment  

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Full Text Available Background/Aim. Autogenous bone grafting has been the gold standard in clinical cases when bone grafts are required for bone defects in dentistry. The study was undertaken to evaluate multilevel designed carbonated hydroxyapatite (CHA obtained by hydrothermal method, as a bone substitute in healing bone defects with or without corticosteroid treatment in rats as assessed by histopathologic methods. Methods. Bone defects were created in the alveolar bone by teeth extraction in 12 rats. The animals were initially divided into two groups. The experimental group was pretreated with corticosteroids: methylprednisolone and dexamethasone, intramuscularly, while the control group was without therapy. Posterior teeth extraction had been performed after the corticosteroid therapy. The extraction defects were fulfilled with hydroxyapatite with bimodal particle sizes in the range of 50-250 ?m and the sample from postextocactional defect of the alveolar bone was analyzed pathohystologically. Results. The histopatological investigations confirmed the biologic properties of the applied material. The evident growth of new bone in the alveolar ridge was clearly noticed in both groups of rats. Carbonated HA obtained by hydrothermal method promoted bone formation in the preformed defects, confirming its efficacy for usage in bone defects. Complete resorption of the material’s particles took place after 25 weeks. Conclusion. Hydroxyapatite completely meets the clinical requirements for a bone substitute material. Due to its microstructure, complete resorption took place during the observation period of the study. Corticosteroid treatment did not significantly affect new bone formation in the region of postextractional defects. [Projekat Ministarstva nauke Republike Srbije, br. 172026

Markovi? Dejan

2014-01-01

55

Ridge Preservation with Modified “Socket-Shield” Technique: A Methodological Case Series  

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Full Text Available After tooth extraction, the alveolar bone undergoes a remodeling process, which leads to horizontal and vertical bone loss. These resorption processes complicate dental rehabilitation, particularly in connection with implants. Various methods of guided bone regeneration (GBR have been described to retain the original dimension of the bone after extraction. Most procedures use filler materials and membranes to support the buccal plate and soft tissue, to stabilize the coagulum and to prevent epithelial ingrowth. It has also been suggested that resorption of the buccal bundle bone can be avoided by leaving a buccal root segment (socket shield technique in place, because the biological integrity of the buccal periodontium (bundle bone remains untouched. This method has also been described in connection with immediate implant placement. The present case report describes three consecutive cases in which a modified method was applied as part of a delayed implantation. The latter was carried out after six months, and during re-entry the new bone formation in the alveolar bone and the residual ridge was clinically evaluated as proof of principle. It was demonstrated that the bone was clinically preserved with this method. Possibilities and limitations are discussed and directions for future research are disclosed.

Markus Glocker

2014-01-01

56

Clinical technique for invasive cervical root resorption  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This clinical case report describes the diagnosis and treatment of an external invasive cervical resorption. A 17-year-old female patient had a confirmed diagnosis of invasive cervical resorption class 4 by cone beam computerized tomography. Although, there was no communication with the root canal, the invasive resorption process was extending into the cervical and middle third of the root. The treatment of the cervical resorption of the lateral incisor interrupted the resorptive process and ...

Silveira, Luiz Fernando Machado; Silveira, Carina Folgearini; Martos, Josue?; Piovesan, Edno Moacir; Ce?sar Neto, Joa?o Batista

2011-01-01

57

Alveolar hypoxia, alveolar macrophages, and systemic inflammation  

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Full Text Available Abstract Diseases featuring abnormally low alveolar PO2 are frequently accompanied by systemic effects. The common presence of an underlying inflammatory component suggests that inflammation may contribute to the pathogenesis of the systemic effects of alveolar hypoxia. While the role of alveolar macrophages in the immune and defense functions of the lung has been long known, recent evidence indicates that activation of alveolar macrophages causes inflammatory disturbances in the systemic microcirculation. The purpose of this review is to describe observations in experimental animals showing that alveolar macrophages initiate a systemic inflammatory response to alveolar hypoxia. Evidence obtained in intact animals and in primary cell cultures indicate that alveolar macrophages activated by hypoxia release a mediator(s into the circulation. This mediator activates perivascular mast cells and initiates a widespread systemic inflammation. The inflammatory cascade includes activation of the local renin-angiotensin system and results in increased leukocyte-endothelial interactions in post-capillary venules, increased microvascular levels of reactive O2 species; and extravasation of albumin. Given the known extrapulmonary responses elicited by activation of alveolar macrophages, this novel phenomenon could contribute to some of the systemic effects of conditions featuring low alveolar PO2.

Gonzalez Norberto C

2009-06-01

58

Working pairs for resorption refrigerator  

International Nuclear Information System (INIS)

systems would be much higher. - Highlights: ? The comparison of three different working pairs operating under resorption cycle was conducted. ? The three working pairs were NH4Cl/MnCl2, NaBr/MnCl2, BaCl2/MnCl2, respectively. ? The mass of refrigerant reacted in different situations were measured and compared. ? Among the LTS studied, NH4Cl is the most suitable to be used in a resorption machine at 0 or below 0 oC.

59

Periosteum: Resorption or Formation Area?  

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Full Text Available Periosteum is a membrane that lines the outer surface of all bones, except at the joints of long bones. Endosteum lines the inner surface of all bones. Periosteal formation is observed in every stage of life, especially in childhood and early adulthood. Formation continues mechanically as a response to load. Periosteal resorption is observed especially in the flat bones in the growing period. In adulthood, resorption is a part of remodeling. The periosteal surface contains fewer osteoclasts than does the endosteal surface, and remodeling on the periosteal surface is much slower. For this reason, adult periosteum is defined as a formation area. Turk Jem 2008; 12: 28-31

Betül U?ur Altun

2008-05-01

60

Primary alveolar hypoventilation  

Science.gov (United States)

Primary alveolar hypoventilation is a rare disorder in which a person does not take enough breaths per ... breathe more deeply or quickly. In people with primary alveolar hypoventilation, this change in breathing does not ...

 
 
 
 
61

Invasive cervical resorption: a review.  

Science.gov (United States)

Invasive cervical resorption is a relatively uncommon form of external root resorption exhibiting no external signs. The resorptive condition is often detected by routine radiographic examination. The clinical features vary from a small defect at the gingival margin to a pink coronal discoloration of the tooth crown resulting in ultimate cavitation of the overlying enamel which is painless unless pulpal or periodontal infection supervenes. Radiographic features of lesions vary from well-delineated to irregularly bordered mottled radiolucencies, and these can be confused with dental caries. A characteristic radiopaque line generally separates the image of the lesion from that of the root canal, because the pulp remains protected by a thin layer of predentin until late in the process. Histopathologically, the lesions contain fibrovascular tissue with resorbing clastic cells adjacent to the dentin surface. More advanced lesions display fibro-osseous characteristics with deposition of ectopic bonelike calcifications both within the resorbing tissue and directly on the dentin surface. How to cite this article: Kandalgaonkar SD, Gharat LA, Tupsakhare SD, Gabhane MH. Invasive Cervical Resorption: A Review. J Int Oral Health 2013;5(6):124-30 . PMID:24453457

Kandalgaonkar, Shilpa D; Gharat, Leena A; Tupsakhare, Suyog D; Gabhane, Mahesh H

2013-12-01

62

Osteoprotegerin-deficient male mice as a model for severe alveolar bone loss: comparison with RANKL-overexpressing transgenic male mice.  

Science.gov (United States)

Periodontitis, an inflammatory disease of periodontal tissues, is characterized by excessive alveolar bone resorption. An increase in the receptor activator of nuclear factor-?B ligand (RANKL) to osteoprotegerin (OPG) ratio is thought to reflect the severity of periodontitis. Here, we examined alveolar bone loss in OPG-deficient (OPG(-/-)) mice and RANKL-overexpressing transgenic (RANKL-Tg) mice. Alveolar bone loss in OPG(-/-) mice at 12 weeks was significantly higher than that in RANKL-Tg mice. OPG(-/-) but not RANKL-Tg mice exhibited severe bone resorption especially in cortical areas of the alveolar bone. An increased number of osteoclasts was observed in the cortical areas in OPG(-/-) but not in RANKL-Tg mice. Immunohistochemical analyses showed many OPG-positive signals in osteocytes but not osteoblasts. OPG-positive osteocytes in the cortical area of alveolar bones and long bones were abundant in both wild-type and RANKL-Tg mice. This suggests the resorption in cortical bone areas to be prevented by OPG produced locally. To test the usefulness of OPG(-/-) mice as an animal model for screening drugs to prevent alveolar bone loss, we administered an antimouse RANKL antibody or risedronate, a bisphosphonate, to OPG(-/-) mice. They suppressed alveolar bone resorption effectively. OPG(-/-) mice are useful for screening therapeutic agents against alveolar bone loss. PMID:23291450

Koide, Masanori; Kobayashi, Yasuhiro; Ninomiya, Tadashi; Nakamura, Midori; Yasuda, Hisataka; Arai, Yoshinori; Okahashi, Nobuo; Yoshinari, Nobuo; Takahashi, Naoyuki; Udagawa, Nobuyuki

2013-02-01

63

Contaminant resorption during soil washing  

Energy Technology Data Exchange (ETDEWEB)

To evaluate the applicability of soil washing to a specific site requires some basic research in how contaminants are bound. Much can be learned from sequential extraction methodology based on micronutrient bioavailability studies wherein the soil matrix is chemically dissected to selectively remove particular fixation mechanisms independently. This procedure uses a series of progressively more aggressive solvents to dissolve the principle phases that make up a soil, however, the published studies do not appear to consider the potential for a contaminant released from one type of site to resorb on another site during an extraction. This physical model assumes no ion exchange or adsorption at sites either previously occupied by other ions, or exposed by the dissolution. Therefore, to make engineering use of the sequential extraction data, the release of contamination must be evaluated relative to the effects of resorption. Time release studies were conducted to determine the optimum duration for extraction to maximize complete destruction of the target matrix fraction while minimizing contaminant resorption. Tests with and without a potassium brine present to inhibit cesium resorption indicated extraction efficiency could be enhanced by as much as a factor of ten using the brine.

Gombert, D.

1993-10-01

64

Contaminant resorption during soil washing  

International Nuclear Information System (INIS)

To evaluate the applicability of soil washing to a specific site requires some basic research in how contaminants are bound. Much can be learned from sequential extraction methodology based on micronutrient bioavailability studies wherein the soil matrix is chemically dissected to selectively remove particular fixation mechanisms independently. This procedure uses a series of progressively more aggressive solvents to dissolve the principle phases that make up a soil, however, the published studies do not appear to consider the potential for a contaminant released from one type of site to resorb on another site during an extraction. This physical model assumes no ion exchange or adsorption at sites either previously occupied by other ions, or exposed by the dissolution. Therefore, to make engineering use of the sequential extraction data, the release of contamination must be evaluated relative to the effects of resorption. Time release studies were conducted to determine the optimum duration for extraction to maximize complete destruction of the target matrix fraction while minimizing contaminant resorption. Tests with and without a potassium brine present to inhibit cesium resorption indicated extraction efficiency could be enhanced by as much as a factor of ten using the brine

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Analysis of the prevalence of different topographical characteristics of the residual ridge in mandibular free-end arches Análise da prevalência de diferentes características topográficas do rebordo residual em arcos mandibulares com extremidades livres  

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Full Text Available This study observed the prevalence of different types of residual ridge inclination in free-ends of mandibles and reported possible correlative factors that may affect resorption. For this purpose, periapical radiographs and individual data collected from a sample of 64 hemiarches were used. Two radiographs were taken of each free-end, and tracing was employed to determine the angles formed by the resorption configuration in the area of the 1st mandibular molar. The following conclusions were drawn: 1 the great majority of alveolar ridges were distally descending; 2 the average angle was wider for users of mandibular removable partial dentures; 3 the results obtained suggest that the type of opposing maxillary arch affects the inclination of mandibular ridges; 4 greater inclination was observed when the 2nd bicuspids of the mandible were the abutment teeth; 5 no significant correlation was established between age, sex and residual ridge resorption.Esta pesquisa constatou a prevalência dos tipos de rebordos residuais no sentido ântero-posterior em extremidades livres inferiores, além de correlacionar alguns fatores que possam influenciar as suas reabsorções. Para isso, utilizamos radiografias periapicais e dados individuais colhidos na amostra de 64 hemiarcos; foram obtidas 2 radiografias de cada área de extremidade livre e, a partir de traçados, determinamos os ângulos formados pela reabsorção na altura do 1º molar inferior. Podemos constatar que: 1º a grande maioria de inclinação encontrada foi de rebordos descendentes para distal; 2º a média de angulação foi maior para usuários de prótese parcial removível inferior; 3º os resultados sugeriram existir influência do tipo de arco antagônico superior na inclinação dos rebordos inferiores; 4º observou-se aumento de inclinação quando os segundos pré-molares inferiores eram os dentes adjacentes ao espaço protético; e 5º não foram encontradas correlações significantes entre idade, sexo e reabsorção do rebordo residual.

Carlos Gramani Guedes

2004-03-01

66

Proteinosis alveolar pulmonar / Pulmonary alveolar proteinosis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish La proteinosis alveolar pulmonar es una enfermedad respiratoria crónica, caracterizada por alteración en el metabolismo del surfactante, lo que determina su acumulación anormal en el espacio alveolar. Es una enfermedad extremadamente rara. Se han reportado solamente 500 casos en la literatura. Se de [...] scribió por primera vez en 1958. Se presenta un caso de proteinosis alveolar pulmonar en un lactante de 2 meses, con desnutrición proteico energética, que ingresa por dificultad respiratoria e hipoxemia, y, con imágenes radiológicas de tipo retículo-nodulillar, en vidrio deslustrado, en el cual se plantea inicialmente el diagnóstico de bronconeumonía. Ante la evolución desfavorable y no respuesta al tratamiento, se realizó un estudio para descartar enfermedades pulmonares crónicas. El paciente fallece y se confirma el diagnóstico por anatomía patológica. Se realiza una revisión del tema. Abstract in english The pulmonary alveolar proteinosis is a chronic respiratory disease characterized by surfactant metabolism alteration determining its abnormal accumulation in the alveolar space. It is a disease very rare and in literature only 500 cases have been reported; it was described for the first time in 195 [...] 8. This is a case presentation of pulmonary alveolar proteinosis in an infant aged 2 months with energetic protein malnutrition admitted due to respiratory difficulty and hypoxemia and with radiologic images of the reticulonodulillary, in frosting glass, where initially is made the diagnosis of bronchopneumonia. In the face of unfavorable evolution and no response to treatment, a study was conducted to rule out chronic pulmonary diseases. Patient died confirming the diagnosis according to the pathologic anatomy. A review on subject is carried out.

Concepción, Sánchez Infante; Anixia, Serrano Sánchez; Roberto, Razón Behar; Cristina, Reyes López.

67

Pulmonary alveolar proteinosis  

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Full Text Available Pulmonary alveolar proteinosis (PAP is a rare pulmonary disease characterised by alveolar accumulation of surfactant. It may result from mutations in surfactant proteins or granulocyte macrophage-colony stimulating factor (GM-CSF receptor genes, it may be secondary to toxic inhalation or haematological disorders, or it may be auto-immune, with anti-GM-CSF antibodies blocking activation of alveolar macrophages. Auto-immune alveolar proteinosis is the most frequent form of PAP, representing 90% of cases. Although not specific, high-resolution computed tomography shows a characteristic “crazy paving” pattern. In most cases, bronchoalveolar lavage findings establish the diagnosis. Whole lung lavage is the most effective therapy, especially for auto-immune disease. Novel therapies targeting alveolar macrophages (recombinant GM-CSF therapy or anti-GM-CSF antibodies (rituximab and plasmapheresis are being investigated. Our knowledge of the pathophysiology of PAP has improved in the past 20 yrs, but therapy for PAP still needs improvement.

B. Crestani

2011-06-01

68

A case report of severe external resorption.  

Science.gov (United States)

External root resorption is a multifactorial process with many causes. Except for transient surface resorption, it is usually considered an irreversible process. Treatment can arrest or retard the resorptive process. Many factors that have been associated with this process include physiologic resorption, local factors, systemic conditions, and idiopathic resorption. This case report documents a 29-year-old white male who suffered a motor vehicle accident and dental trauma nine years ago. The accident resulted in the lateral displacement of the maxillary right canine. The maxillary right lateral incisor, right central incisor and left central incisors were avulsed. The right central incisor was never recovered from the accident site. The other teeth were replanted 90 minutes after the accident and rigidly splinted for six months. They then received root canal treatment, approximately one month after the splint was removed (seven months from time of the trauma). On annual examination, the patient complained of a loose maxillary fixed prosthesis. He was diagnosed with severe external resorption on the right lateral and left central incisors, and severe external replacement resorption on the right canine. This case report reviews the current trends in the treatment of avulsed teeth and the resorptive process. PMID:8032993

Ford, G S; Baisden, M; Hoen, M; Quigley, N; Camp, L

1994-06-01

69

Preeruptive intracoronal resorption observed in 13 patients  

DEFF Research Database (Denmark)

The literature on preeruptive intracoronal resorption is sparse, comprising mainly reports of single patients. This study includes 13 patients with preeruptive intracoronal resorption, forwarded for consultation regarding diagnostics and etiology. The purposes were to determine which teeth are affected by the condition and describe how the defect is manifested radiographically.

Kjær, Inger; Steiniche, Kirsten

2012-01-01

70

Root Resorption in Orthodontics: Literature Review  

Directory of Open Access Journals (Sweden)

Full Text Available This article is a literature review about external root resorption and the biological and mechanical factors that predispose its appearance in orthodontic patients. Genetic, systemic and pharmacological factors, chronological and dental age, nutritional status, gender, race, habits, tooth morphology, size and number, resorptions and dental trauma previous to periapical infections, occlusal factors and specific vulnerability to resorption are described. Among mechanical factors, the type of appliances, the type of movement, duration of forces, and duration of treatment are included. Since external root resorption is considered an undesirable side effect associated with orthodontic movement, it is responsibility of the orthodontist to be aware of all these risk factors for external root resorption, for its timely prevention or interception.

María Alexandra Lozano-Chourio

2009-12-01

71

Alveolar Epithelial ?2-Adrenergic Receptors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

?2-adrenergic receptors are present throughout the lung, including the alveolar airspace, where they play an important role for regulation of the active Na+ transport needed for clearance of excess fluid out of alveolar airspace. ?2-adrenergic receptor signaling is required for up-regulation of alveolar epithelial active ion transport in the setting of excess alveolar edema. The positive, protective effects of ?2-adrenergic receptor signaling on alveolar active Na+ transport in normal and ...

Mutlu, Go?khan M.; Factor, Phillip

2008-01-01

72

Invasive cervical resorption: report on two cases.  

Science.gov (United States)

Invasive cervical resorption is a relatively uncommon form of external root resorption that may lead to tooth loss. This article presents the clinical and radiologic diagnoses and treatment modalities of invasive cervical resorption in 2 patients. In the first case, we did a slow orthodontic forced eruption to make the bone grow coronally. After 6 months, the tooth was extracted and an immediate implant was placed. Eight months later a zirconia crown was cemented. In the second case, we performed root canal treatment followed by a composite reconstruction of the defect. These 2 cases illustrate different approaches based on the extent of the defect. PMID:20580285

Roig, Miguel; Morelló, Sergio; Mercadé, Montse; Durán-Sindreu, Fernando

2010-10-01

73

Hybrid distraction: a novel method for distraction osteogenesis of the alveolar process.  

Science.gov (United States)

Segmental distraction osteogenesis of the anterior alveolar process is a sufficient method to enlarge the alveolar arch. Indications for this method are dental crowding, retroalveolism, and leveling of the curve of Spee. However, after the distraction period, the anterior alveolar segment often shows an unfavorable inclination resulting in nonphysiologic load on the lower incisors.The aim of this paper was to introduce a new approach in segmental distraction osteogenesis of the anterior alveolar process. This new method combines 2 different surgical techniques: a segmental osteotomy for the alveolar ridge with instant fixation in the desired position and a distraction procedure for the alveolar segment. This hybrid distraction avoids an unfavorable inclination of the lower incisors after front-block distraction procedures. PMID:23147294

Zemann, Wolfgang; Metzler, Philipp; Jacobsen, Christine; Obwegeser, Joachim Anton

2012-11-01

74

Pulmonary alveolar proteinosis.  

Science.gov (United States)

Pulmonary alveolar proteinosis is a rare but potentially treatable disease, characterized by impaired surfactant metabolism that leads to accumulation in the alveoli of proteinaceous material rich in surfactant protein and its component. Novel insights from an animal model aided the discovery of granulocyte macrophage colony stimulating factor (GM-CSF) antibodies as a pathogenetic mechanism in human pulmonary alveolar proteinosis. The vast majority of pulmonary alveolar proteinosis occurs as an autoimmune disease; less commonly, it is congenital or secondary to an underlying disorder such as infection, hematological malignancy, or immunodeficiency. The subacute indolent course of this disease often delays the diagnosis by months to years. Crazy-paving appearance in a geographic distribution is a characteristic feature of this disease visible on high-resolution computed tomography (CT). A definitive diagnosis, however, requires lung biopsy, which typically shows partial or complete filling of alveoli with periodic-acid-Schiff-positive granular and eosinophilic material in preserved alveolar architecture. Patients with minimal symptoms are managed conservatively, whereas patients with hypoxemia require a more aggressive approach. Whole-lung lavage is the most widely accepted therapy for symptomatic pulmonary alveolar proteinosis. Correction of GM-CSF deficiency with exogenous GM-CSF is an alternative therapy. The combination of a systemic treatment (GM-CSF) and a local treatment (whole-lung lavage) augmenting the action of one another is a promising new approach. As the knowledge about this rare disease increases, the role of novel therapies is likely to be better defined and optimized. PMID:21496372

Khan, Ajmal; Agarwal, Ritesh

2011-07-01

75

The four mechanisms of dental resorption initiation  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O presente trabalho propõe-se a apresentar uma classificação, com aplicação clínica, para as reabsorções dentárias, para que o diagnóstico seja objetivo e imediatamente ligado à causa do problema, levando automaticamente o clínico ao provável plano de tratamento e a um prognóstico preciso. Com esse [...] objetivo, sugerimos agrupar cada caso clínico de reabsorção dentária em um dos seguintes grupos: 1) Reabsorções radiculares pela morte dos cementoblastos, com manutenção dos restos epiteliais de Malassez. 2) Reabsorções radiculares pela morte dos cementoblastos e dos restos epiteliais de Malassez. 3) Reabsorções dentárias pela morte dos odontoblastos, com manutenção da vitalidade pulpar. 4) Reabsorções dentárias pela exposição direta da dentina ao tecido conjuntivo gengival, nos gaps da junção amelocementária. Abstract in english The aim of this study is to present a classification with a clinical application for root resorption, so that diagnosis will be more objective and immediately linked to the source of the problem, leading the clinician to automatically develop the likely treatment plan with a precise prognosis. With [...] this purpose, we suggest putting together all diagnosed dental resorptions into one of these four criteria: 1) Root resorption caused by cementoblast cell death, with preservation of the Malassez epithelial rests. 2) Root resorption by cementoblasts and Malassez epithelial rests death. 3) Dental resorption by odontoblasts cell death with preservation of pulp vitality. 4) Dental resorption by direct exposure of dentin to gingival connective tissue at the cementoenamel junction gaps.

Alberto, Consolaro.

76

Predisposing factors to severe external root resorption associated to orthodontic treatment  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVE: The aim of this study was to evaluate predisposing factors among patients who developed moderate or severe external root resorption (Malmgren's grades 3 and 4, on the maxillary incisors, during fixed orthodontic treatment in the permanent dentition. METHODS: Ninety-nine patients who underwent orthodontic treatment with fixed edgewise appliances were selected. Patients were divided into two groups: G1 - 50 patients with no root resorption or presenting only apical irregularities (Malmgren's grades 0 and 1 at the end of the treatment, with mean initial age of 16.79 years and mean treatment time of 3.21 years; G2 - 49 patients presenting moderate or severe root resorption (Malmgren's grades 3 and 4 at the end of treatment on the maxillary incisors, with mean initial age of 19.92 years and mean treatment time of 3.98 years. Periapical radiographs and lateral cephalograms were evaluated. Factors that could influence the occurrence of severe root resorption were also recorded. Statistical analysis included chi-square tests, Fisher's exact test and independent t tests. RESULTS: The results demonstrated significant difference between the groups for the variables: Extractions, initial degree of root resorption, root length and crown/root ratio at the beginning, and cortical thickness of the alveolar bone. CONCLUSION: It can be concluded that: Presence of root resorption before the beginning of treatment, extractions, reduced root length, decreased crown/root ratio and thin alveolar bone represent risk factors for severe root resorption in maxillary incisors during orthodontic treatment.OBJETIVO: avaliar os fatores comuns aos pacientes que desenvolveram reabsorção radicular externa moderada ou severa (graus 3 e 4 de Malmgren nos incisivos superiores, durante o tratamento ortodôntico fixo na dentição permanente. MÉTODOS: foram selecionados 99 pacientes que iniciaram o tratamento ortodôntico fixo com a técnica Edgewise. Os pacientes foram divididos em dois grupos: G1 - 50 pacientes que concluíram o tratamento com ausência de reabsorções radiculares ou apresentando apenas irregularidades apicais (graus 0 e 1 de Malmgren, com idade média inicial de 16,79 anos e tempo de tratamento médio de 3,21 anos; G2 - 49 pacientes que finalizaram o tratamento apresentando reabsorção radicular moderada ou severa (graus 3 e 4 de Malmgren nos incisivos superiores, com idade média inicial de 19,92 anos e tempo de tratamento médio de 3,98 anos. As radiografias periapicais e telerradiografias foram avaliadas, além de diversos fatores que pudessem influenciar a ocorrência de uma reabsorção severa. A análise estatística incluiu o testes qui-quadrado, teste exato de Fisher e teste t independente. RESULTADOS: foi demonstrada a presença de diferença significativa entre os grupos para as variáveis realização de extrações, grau de reabsorção radicular inicial, comprimento radicular, proporção coroa/raiz e da espessura da cortical óssea alveolar. CONCLUSÃO: pode-se concluir que são fatores de risco para reabsorção radicular severa nos incisivos superiores, durante o tratamento ortodôntico, a presença de reabsorção radicular antes do início do tratamento, a realização de extrações, o comprimento radicular reduzido, a proporção coroa/raiz diminuída e a espessura óssea alveolar fina.

Gracemia Vasconcelos Picanço

2013-02-01

77

Restoration of the maxillary anterior tooth using immediate implantation with simultaneous ridge augmentation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Atrophy is most severe during the first month of post-extraction in the anterior maxilla with the degree of horizontal bone resorption being nearly twice as high as that of vertical bone resorption. The loss of the buccal alveolar plate following tooth extraction may lead to palatal implant positioning of the implants. Thus, immediate or early implant placement in the extraction socket has been suggested, because it would reduce the time period and the number of surgical intervention and yiel...

Park Jun-Beom

2010-01-01

78

Combined method of treating a complete absence of teeth in the mandible and the prevention of alveolar atrophy  

Directory of Open Access Journals (Sweden)

Full Text Available An alternative fully removable laminar prosthesis on the lower jaw design with poor fixation and sharp atrophy of alveolar ridge - a combined denture with girder construction of titanium, fixed on the implants

Perunov A.Y.

2011-03-01

79

[Analysis of alveolar bone].  

Science.gov (United States)

Several techniques such as intra-oral dental radiographs, dental panoramic radiographs, computed tomography and dual energy x-ray absorptiometry have been used to evaluate the effects of oral diseases such as periodontal disease and systemic diseases such as osteoporosis on quantity and quality of alveolar bone of the jaws. Advanced imaging such as magnetic resonance imaging might also be applied to evaluate them in the future. However, the analysis and evaluation of alveolar bone should be carefully performed in consideration of some limitations included in each technique. PMID:17272876

Taguchi, Akira

2007-02-01

80

The relevance of leukotrienes for bone resorption induced by mechanical loading.  

Science.gov (United States)

5-Lipoxygenase (5-LO) metabolites are important pro-inflammatory lipid mediators. However, much still remains to be understood about the role of such mediators in bone remodeling. This study aimed to investigate the effect of 5-LO metabolites, LTB4 and CysLTs, in a model of mechanical loading-induced bone remodeling. Strain-induced tooth movement and consequently alveolar bone resorption/apposition was achieved by using a coil spring placed on molar and attached to incisors of C57BL6 (wild-type-WT), 5-LO deficient mice (5-LO(-/-)) and mice treated with 5-LO inhibitor (zileuton-ZN) or with antagonist of CysLTs receptor (montelukast-MT). The amount of bone resorption and the number of osteoclasts were determined morphometrically. The expression of inflammatory and bone remodeling markers in periodontium was analyzed by qPCR. Osteoclast differentiation and TNF-? production were evaluated in vitro using RAW 264.7 cells treated with LTB4 or LTD4. Bone resorption, TRAP(+) cells and expression of Tnfa, Il10 and Runx2 were significantly diminished in 5-LO(-/-), ZN- and MT-treated mice. The expression of Rank was also reduced in 5-LO(-/-) and MT-treated mice. Accordingly, LTB4 and LTD4 in association with RANKL promoted osteoclast differentiation and increased TNF-? release in vitro. These data demonstrate that the absence of 5-LO metabolites, LTB4 and CysLTs reduces osteoclast recruitment and differentiation, consequently diminishing bone resorption induced by mechanical loading. Thus, 5-LO might be a potential target for controlling bone resorption in physiological and pathological conditions. PMID:25270168

Moura, A P; Taddei, S R A; Queiroz-Junior, C M; Madeira, M F M; Rodrigues, L F D; Garlet, G P; Souza, D G; Machado, F S; Andrade, I; Teixeira, M M; Silva, T A

2014-12-01

 
 
 
 
81

Alveolar bone necrosis and spontaneous tooth exfoliation in an HIV-seropositive subject with herpes zoster.  

Science.gov (United States)

Herpes zoster in the distribution of the maxillary and mandibular divisions of the trigeminal nerve is characterized by painful vesicular eruptions of the skin and oral mucosa in the distribution of the affected nerves. Oral complications may occur, including post-herpetic neuralgia, devitalization of teeth, abnormal development of permanent teeth, root resorption and periapical lesions. In cases where necrosis of the alveolar bony process occur it may be preceded or accompanied by spontaneous exfoliation of teeth. This usually follows the resolution of the acute phase of HZ and is more prevalent in HIV-seropositive than in HIV-seronegative subjects. A case of HZ of the trigeminal nerve in an HIV-seropositive subject, with complications of necrosis of alveolar bony process, external root resorption and tooth exfoliation is presented and the literature of HIV-associated HZ is reviewed. PMID:18561810

Feller, L; Wood, N H; Raubenheimer, E J; Meyerov, R; Lemmer, J

2008-03-01

82

RABDOMIOSARCOMA ALVEOLAR DE UTERO  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish Los rabdomiosarcomas constituyen un tipo raro de sarcoma que se origina en las células mesenquimáticas que van a derivar en músculo estriado. De ocurrencia mayoritaria en la infancia (50-55% de los sarcomas de los niños, de ellos el 70% ocurre en la primera década). Se clasifican en forma histológic [...] a en embriones, botriodes, alveolar y pleomórficas. Estos tumores se diagnostican en raras ocasiones. Se etapifican según la IRSG de Estados Unidos. Debido a los pobres resultados se evalúa la sobrevida a los 2 años (90% de mortalidad a los dos años). A continuación presentamos el poco afortunado caso de una paciente manejada en nuestro servicio, en cuyo estudio patológico se demostró un rabdomiosarcoma alveolar de útero Abstract in english Rabdomyosarcoma constitutes a rare type of sarcoma that it is originated in the mesenchymal cells that are going to derive in striated muscle. Are more common in childhood (50-55% of sarcomas of the children, of them 70% happens in a the first decade). They are classified histologicaly in embryonic, [...] botryoid, alveolar and pleomorphic. These tumors are diagnosed very seldom. We present the unfortunate case of a patient handled in our service, in whose pathological study a uterine alveolar rhabdomyosarcoma was demonstrated

Ernesto, Hurel M; Gregorio, Evans M; Ronald, Poulsen R; Hugo, Gómez P.

83

RABDOMIOSARCOMA ALVEOLAR DE UTERO  

Directory of Open Access Journals (Sweden)

Full Text Available Los rabdomiosarcomas constituyen un tipo raro de sarcoma que se origina en las células mesenquimáticas que van a derivar en músculo estriado. De ocurrencia mayoritaria en la infancia (50-55% de los sarcomas de los niños, de ellos el 70% ocurre en la primera década. Se clasifican en forma histológica en embriones, botriodes, alveolar y pleomórficas. Estos tumores se diagnostican en raras ocasiones. Se etapifican según la IRSG de Estados Unidos. Debido a los pobres resultados se evalúa la sobrevida a los 2 años (90% de mortalidad a los dos años. A continuación presentamos el poco afortunado caso de una paciente manejada en nuestro servicio, en cuyo estudio patológico se demostró un rabdomiosarcoma alveolar de úteroRabdomyosarcoma constitutes a rare type of sarcoma that it is originated in the mesenchymal cells that are going to derive in striated muscle. Are more common in childhood (50-55% of sarcomas of the children, of them 70% happens in a the first decade. They are classified histologicaly in embryonic, botryoid, alveolar and pleomorphic. These tumors are diagnosed very seldom. We present the unfortunate case of a patient handled in our service, in whose pathological study a uterine alveolar rhabdomyosarcoma was demonstrated

Ernesto Hurel M

2003-01-01

84

Primary pulmonary alveolar proteinosis  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction. Pulmonary alveolar proteinosis is an uncommon disease characterized by the accumulation of surfactant proteins and phospholipids within the alveolar spaces. Acquired disease can be idiopathic (primary and secondary. The prevalence of acquired pulmonary alveolar proteinosis is about 0.37 per 100,000 persons. Common symptoms are dyspnea and cough. Chest X-ray shows bilateral perihilar infiltrates. Open-lung biopsy is the gold standard for the diagnosis. Treatment includes whole-lung lavage, application of granulocyte-macrophage colonystimulating factor and lung transplantation. Case report. We reported a 51 year-old man with primary form of the disease. It was the second case of this extremely rare disease in the past 30 years in our clinic. The symptoms were longlasting dry cough, fever and physical deterioration. Chest Xray revealed bilateral pulmonary infiltrates; computed tomography showed patchy ground-glass opacification with interlobular thickening. The diagnosis was established by open lung biopsy. Additional tests were performed to exclude secondary form of the disease. Conclusion. We presented a rare clinical entity with typical clinical features and clinical and radiological course of the disease, in order to improve differential diagnostic approach to patients with bilateral lung infiltrations. In patients with pulmonary alveolar proteinosis timely diagnosis and adequate treatment can improve a prognosis.

Šarac Sanja

2012-01-01

85

Involvement of calpain in osteoclastic bone resorption.  

Science.gov (United States)

There is increasing evidence that calpain contributes to the reorganization of the cytoskeleton in the integrin-mediated signaling pathway. Osteoclastic bone resorption requires cell-matrix contact, an event mediated by integrin alphavbeta3, and subsequent cytoskeletal reorganization to form characteristic membrane domains such as the sealing zone and ruffled border. In this study, therefore, we investigated whether calpain is involved in osteoclastic bone resorption. Membrane-permeable calpain inhibitors suppress the resorption activity of human osteoclasts, but an impermeable inhibitor does not. Upon the attachment of osteoclasts to bone, micro-calpain is translocated from the cytosolic to the cytoskeletal fraction and is autolytically activated. Both the activation of micro-calpain and the formation of actin-rings, the cytoskeletal structures essential for bone resorption, are inhibited by membrane-permeable calpain inhibitors. The activated micro-calpain in osteoclasts selectively cleaves talin, which links the matrix-recognizing integrin to the actin cytoskeleton. These findings suggest that calpain is a regulator of the bone resorption activity of osteoclasts through reorganization of the cytoskeleton related to actin-ring formation. PMID:15809334

Hayashi, Masami; Koshihara, Yasuko; Ishibashi, Hideaki; Yamamoto, Seizo; Tsubuki, Satoshi; Saido, Takaomi C; Kawashima, Seiichi; Inomata, Mitsushi

2005-03-01

86

Bilateral condylar resorption in down syndrome.  

Science.gov (United States)

Asymptomatic idiopathic condylar resorption is a rare disease of difficult diagnosis and treatment. We review the literature about this rare condition and report a case of a patient, affected by Down syndrome, who underwent a complete untreated bilateral condylar resorption in adolescence and then developed pain on chewing only 20 years later. Despite a precise orthodontic and surgical therapeutic plan, treatment had to be discontinued because of patient lack of compliance. This case is the first of its kind to be reported and emphasizes the need for special attention in patients with disability. PMID:25376143

Grippaudo, Cristina; Grippaudo, Francesca Romana; Marianetti, Tito Matteo; Cacucci, Laura; Deli, Roberto; Pelo, Sandro

2014-11-01

87

Pulmonary alveolar microlithiliasis  

International Nuclear Information System (INIS)

We report a patient with plmonary alveolar microlithiliasis who was admitted to King Abdul-Aziz Hospital, Makkah, Kingdom of Saudi Arabia with chest pain, shortness of breath dry cough and swelling of lower limbs.The patient underwent chest radiolgraphs and computerized tomography scan showing multiple diffuse, almost symmetrical bilateral micronodulor opacities of calicific density. The diagnosis was confirmed after percuraneous lung biopsy from the patient. Cardiokinetics, diuretics and oxygen were administerd with slight improvement. (author)

88

[Unusual alveolar proteinosis].  

Science.gov (United States)

Pulmonary alveolar proteinosis (PAP), a rare infiltrative disease of unknown aetiology, is characterized by an accumulation of abnormal lung surfactant in the alveoli. The diagnosis is based on the results of the bronchoalveolar lavage (BAL) and sometimes on the lung biopsy. The authors report the case of a 49-year-old woman who was hospitalized for chronic expectoration of the membranes. The chest X-ray revealed alveolar opacities in the lowest part of the right lung. The chest CT scan detected alveolar ground glass opacities with interlobular thickening involving the middle lobe. The BAL was opaque with periodic acid-Schiff stain-positive acellular material. The anatomopathology analysis of the membranes concludes as to the presence of granular eosinophilic material and the absence of neoplasic cells or hydatidous membranes. The diagnosis of PAP was established. Since functional deterioration was not detected, therapy was based on physiotherapy alone. The evolution was favourable, with the disappearance of the symptomatology and the normalisation of the chest X-ray. This observation shows an unusual presentation of PAP based on membrane expectoration and unusual localized lesions. PMID:21665079

Boussoffara, L; Boudawara, N; Knani, J; Zantour, B; Khouaja, I

2011-06-01

89

Theoretical basis of alveolar sampling.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The conditions under which the partial pressure of a solvent in the alveolar gas is likely to provide a valid index of its partial pressure in the mixed venous blood, and thus of whole-body exposure, is explored on a theoretical basis. Under steady-state conditions, providing the solvent's blood/gas partition coefficient exceeds 10, its mixed venous and alveolar pressures will agree within 10% and become virtually identical during the prolonged expiration necessary to obtain an alveolar sampl...

Kelman, G. R.

1982-01-01

90

External root resorption after bleaching: a case report.  

Science.gov (United States)

An external root resorption occurred after bleaching and was diagnosed radiographically in a 26-year-old female dental assistant. The resorption was noticed 6 months after bleaching. The involved tooth had no history of trauma. An attempt to stop the resorption by using calcium hydroxide failed. The perforation was corrected surgically with amalgam. PMID:1745520

al-Nazhan, S

1991-11-01

91

Regional aggressive root resorption caused by neuronal virus infection  

DEFF Research Database (Denmark)

During orthodontic treatment, root resorption can occur unexplainably. No clear distinction has been made between resorption located within specific regions and resorption occurring generally in the dentition. The purpose is to present cases with idiopathic (of unknown origin) root resorption occurring regionally. Two cases of female patients, 26 and 28 years old, referred with aggressive root resorption were investigated clinically and radiographically. Anamnestic information revealed severe virus diseases during childhood, meningitis in one case and whooping cough in the other. One of the patients was treated with dental implants. Virus spreading along nerve paths is a possible explanation for the unexpected resorptions. In both cases, the resorptions began cervically. The extent of the resorption processes in the dentition followed the virus infected nerve paths and the resorption process stopped when reaching regions that were innervated differently and not infected by virus. In one case, histological examination revealed multinuclear dentinoclasts. The pattern of resorption in the two cases indicates that innervation is a factor, which under normal conditions may protect the root surface against resorption. Therefore, the normal nerve pattern is important for diagnostics and for predicting the course of severe unexpected root resorption.

Kjær, Inger; StrØm, Carsten

2012-01-01

92

[Calcitonin as an alternative treatment for root resorption].  

Science.gov (United States)

Inflammatory root resorption is a common finding following trauma and will cause eventual destruction of the tooth root if left untreated. This study examined the effects of intrapulpal application of calcitonin, a hormone known to inhibit osteoclastic bone resorption, on experimental inflammatory root resorption induced in monkeys. Results were histologically evaluated using a morphometric technique and revealed that calcitonin was an effective medicament for the treatment of inflammatory root resorption. It was concluded that this hormone could be a useful therapeutic adjunct in difficult cases of external root resorption. PMID:2576918

Pierce, A; Berg, J O; Lindskog, S

1989-01-01

93

Pulmonary alveolar proteinosis  

Directory of Open Access Journals (Sweden)

Full Text Available Pulmonary alveolar proteinosis is a rare disease characterized by the accumulation of lipoproteinosis material within the alveoli. A 36 age male patient applied to our hospital with dyspnea that began 5 months ago. Bilateral diffuse infiltration on postero-anterior chest graphy was seen. Arterial blood gas measurements (ABG was: pH:7.44, pCO2: 36 mmHg, pO2: 49 mmHg, SaO2: 85%, HCO3: 24 mmol/L. High resolution computed tomography (HRCT reported as bilateral diffuse ground glass areas and interlobuler septal thickening on this areas. Asido resistant bacillus was negative in sputum at three times and was also negative in post bronchoscopic sputum and bronchoalveoler lavage material. Wedge resection was made by video-assisted thoracoscopic surgery. Histopathology report of biopsy material revealed “Pulmonary alveolar proteinosis (PAP”. Massive lung lavage under general anesthesia was planned for patient. Clinical improvement was seen in patient beginning from admission and ABG measurements entered the recovery trend in follow-up. Partial pressure of oxygen was increased to 65 mmHg and patient was followed without lung lavage. Control chest radiography and HRCT showed significant radiological improvement. After three months, radiological lesions had completely regressed at control HRCT. As a result, in patients with symptoms and radiologically bilateral diffuse infiltration physicians should consider PAP as a rare disease in the differential diagnosis.

Hadice Selimo?lu ?en

2011-06-01

94

[Mechanism of osteoclast in bone resorption].  

Science.gov (United States)

Osteoclast, a huge coenocytes,originates from mononuclear macrophages or monocytic series hematopoietic precursor cell, plays an important role in the progree of bone resorption. Formation and abnormal activity of osteoclast may cause osteoprosis, rheumatoid arthritis and aseptic loosening after arthroplasty. Therefore, osteoclast is the target for treating these disease. At present, a lot of study on formation of osteoclast were reported, but the study on how to identify and degradation of bone tissue is not yet reported. Bone mineral are seen as important component of identifing osteoclast, and the research suggested that bone matrix is not the essential ingredients of activiting osteoclast, petri dish covered by vitronectin also can make osteoclast occure certain form of bone resorption, vitronectin plays an significant role in activiting osteoclast. Otherwise, the research found that swallowing and secretion of bone matrix degradation products is benefit for differentiation of osteoclast and maintain of function, and this may be therapeutic target for treatment of musculoskeletal disorders. PMID:25241478

Ti, Yun-Fan; Wang, Rui; Zhao, Jian-Ning

2014-06-01

95

TDAG8 activation inhibits osteoclastic bone resorption.  

Science.gov (United States)

Although the roles of acids in bone metabolism are well characterized, the function of proton-sensing receptors in bone metabolism remains to be explored. In this study, we evaluated the role of proton-sensing receptor T-cell death-associated gene 8 (TDAG8) in osteoclastic activity during bone loss after ovariectomy. Through observations of bone mineral content, we found that pathological bone resorption was significantly exacerbated in mice homozygous for a gene trap mutation in the Tdag8 gene. Furthermore, osteoclasts from the homozygous mutant mice resorbed calcium in vitro more than the osteoclasts from the heterozygous mice did. Impaired osteoclast formation under acidic conditions was ameliorated in cultures of bone marrow cells by Tdag8 gene mutation. Extracellular acidification changed the cell morphology of osteoclasts via the TDAG8-Rho signaling pathway. These results suggest that the enhancement of TDAG8 function represents a new strategy for preventing bone resorption diseases, such as osteoporosis. PMID:24221084

Hikiji, Hisako; Endo, Daisuke; Horie, Kyoji; Harayama, Takeshi; Akahoshi, Noriyuki; Igarashi, Hidemitsu; Kihara, Yasuyuki; Yanagida, Keisuke; Takeda, Junji; Koji, Takehiko; Shimizu, Takao; Ishii, Satoshi

2014-02-01

96

Lipoxin A(4) activates alveolar epithelial sodium channel, Na,K-ATPase, and increases alveolar fluid clearance.  

Science.gov (United States)

Edema fluid resorption is critical for gas exchange, and both alveolar epithelial sodium channel (ENaC) and Na,K-ATPase are accredited with key roles in the resolution of pulmonary edema. Alveolar fluid clearance (AFC) was measured in in situ ventilated lungs by instilling isosmolar 5% BSA solution with Evans Blue-labeled albumin tracer (5 ml/kg) and measuring the change in Evans Blue-labeled albumin concentration over time. Treatment with lipoxin A4 and lipoxin receptor agonist (5(S), 6(R)-7-trihydroxymethyl 17 heptanoate) significantly stimulated AFC in oleic acid (OA)-induced lung injury, with the outcome of decreased pulmonary edema. Lipoxin A4 and 5(S), 6(R)-7-trihydroxymethyl 17 heptanoate not only up-regulated the ENaC ? and ENaC ? subunits protein expression, but also increased Na,K-ATPase ?1 subunit protein expression and Na,K-ATPase activity in lung tissues. There was no significant difference of intracellular cAMP level between the lipoxin A4 treatment and OA group. However, the intracellular cGMP level was significantly decreased after lipoxin A4 treatment. The beneficial effects of lipoxin A4 were abrogated by butoxycarbonyl-Phe-Leu-Phe-Leu-Ph (lipoxin A4 receptor antagonist) in OA-induced lung injury. In primary rat alveolar type II epithelial cells stimulated with LPS, lipoxin A4 increased ENaC ? and ENaC ? subunits protein expression and Na,K-ATPase activity. Lipoxin A4 stimulated AFC through activation of alveolar epithelial ENaC and Na,K-ATPase. PMID:23470626

Wang, Qian; Lian, Qing-Quan; Li, Ru; Ying, Bin-Yu; He, Qian; Chen, Fang; Zheng, Xia; Yang, Yi; Wu, De-Rong; Zheng, Sheng-Xing; Huang, Chang-Jiang; Smith, Fang Gao; Jin, Sheng-Wei

2013-05-01

97

Periapical tissue reactions to calcium hydroxide and MTA after external root resorption as a sequela of delayed tooth replantation.  

Science.gov (United States)

Clinical experience has shown that most avulsed teeth are replanted after a long extra-alveolar time and dry or inadequate wet storage, causing necrosis of periodontal ligament cells. This condition invariably leads to development of external root resorption, leaving the filling material in contact with the periapical connective tissues. In this study, the periapical tissue reactions to calcium hydroxide (CH) and mineral trioxide aggregate (MTA) were evaluated after occurrence of external root resorption as an expected sequela of delayed tooth replantation. Twenty male Wistar rats (Rattus norvegicus, albinus) had their right upper incisor extracted and maintained in dry storage for 60 min. Then, the dental papilla, enamel organ, pulp tissue, and periodontal ligament were removed, and the teeth were immersed in a 2% acidulated phosphate sodium fluoride solution, pH 5.5, for 10 min. The teeth were randomly assigned into two groups (n = 10), in which the canals were filled with either a CH and saline paste (CH group) or MTA (MTA group). The sockets were irrigated with saline, and the teeth were replanted. After 80 days, it was possible to observe large areas of replacement root resorption and some areas of inflammatory root resorption in both groups. More severe inflammatory tissue reaction was observed in contact with calcium hydroxide compared with the mineral trioxide aggregate. New bone formation was more intense at the bottom of the socket in the MTA group. In conclusion, as far as periapical tissue compatibility is concerned, intracanal MTA can be considered as a viable option for root canal filling in delayed tooth replantation, in which external root resorption is an expected sequela. PMID:22151580

Marão, Heloisa Fonseca; Panzarini, Sônia Regina; Aranega, Alessandra Marcondes; Sonoda, Celso Koogi; Poi, Wilson Roberto; Esteves, Jônatas Caldeiras; Silva, Pedro Ivo Santos

2012-08-01

98

Alveolar soft-part sarcoma  

International Nuclear Information System (INIS)

Alveolar soft-part sarcoma usually arises from the soft tissue of the lower extremity, but may arise from the orbit, retroperitoneum and else where, in both children and adults. The tumors grow slowly, may invade the underlying bone, and eventually may metastasis widely through the blood stream. Recently, we experienced 5 cases of alveolar soft-part sarcoma originated from thigh, lower leg, inguinal region, retroperitoneum and orbit. The radiologic findings are soft tissue mass (2 cases) with underlying bony destruction (3 cases), lung metastasis (2 cases). Although rare, alveolar soft-part sarcoma should be included in the differential diagnosis of soft tissue tumor arising from the lower extremity

99

Alveolar macrophages and the diagnosis of drowning  

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In the present study, we examined the number of alveolar macrophages in lung tissue from 17 cases of fresh water drowning, 22 cases of acute death and 6 cases of lung emphysema. When counting only the number of alveolar macrophages per alveolus without consideration of the alveolar size we found no relevant differences between the groups investigated. To exclude any influence of the alveolar size on the results the surface density of the alveolar macrophages and interstitial tissue was estima...

Betz, P.; Nerlich, A.; Penning, R.; Eisenmenger, Wolfgang

1993-01-01

100

Bioceramics composition modulate resorption of human osteoclasts.  

Science.gov (United States)

Biomaterials used in bone regeneration are designed to be gradually resorbed by the osteoclast and replaced by new bone formed through osteoblastic activity. The aim of the present study is to analyze the role of osteoclasts in the resorption process. The attachment of human osteoclasts and the appearance of their resorption lacunae, when cultured on either the resorbable crystalline, calcium orthophosphate materials or on the long-term stable bioceramic material was investigated. The resorbable materials contain Ca10[K,Na](PO4)7 (AW-Si) and Ca2KNa(PO4)2 (GB14, GB9 & D9/25) as their main crystal phases, however they differ in their total solubility. These differences result from small variations in the composition. The long-term stable material consist of about 30% fluorapatite beside calcium zirconium phosphate (Ca5(PO4)3F + CaZr4(PO4)6) and shows a very small solubility. AW-Si has an alkali containing crystalline phase, Ca10[K,Na](PO4). While GB14, GB9 and D9/25 contain the crystalline phase Ca2KNa(PO4)2 with small additions of crystalline and amorphous diphosphates and/or magnesium potassium phosphate (GB14). D9/25 and AW-Si is less soluble compared to GB14, and GB9 among the resorbable materials. Resorbable and long-term stable materials vary in their chemical compositions, solubility, and surface morphology. Osteoclasts modified the surface in their attempts to resorb the materials irrespective of the differences in their physical and chemical properties. The depth and morphology of the resorption imprints were different depending on the type of material. These changes in the surface structure created by osteoclasts are likely to affect the way osteoblasts interact with the materials and how bone is subsequently formed. PMID:16362222

Ramaswamy, Y; Haynes, D R; Berger, G; Gildenhaar, R; Lucas, H; Holding, C; Zreiqat, H

2005-12-01

 
 
 
 
101

Alveolar proteinosis in Behçet's disease.  

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A 51-year-old man with Behçet's disease complained of fever, dry cough and dyspnea during exertion. Chest CT showed ground glass opacities with interstitial septal thickening in both lungs. Bronchoalveolar lavage (BAL) revealed amorphous and lipoproteinaceous material that was periodic acid-Schiff (PAS) stain positive. Transbronchial biopsy specimen demonstrated PAS positive alveolar eosinophilic material consistent with pulmonary alveolar proteinosis. Serum anti-granulocyte-macrophage colony stimulating factor (GM-CSF) antibody was negative. Recent studies have reported anti-GMCSF not present in the the serum of patients with secondary pulmonary alveolar proteinosis (PAP) but they have not reported so in patients with idiopathic PAP. We report a case of alveolar proteinosis in the setting of Behçet's disease with spontaneous remission. PMID:22958601

Tetikkurt, Cuneyt; Tetikkurt, Seza; Ozdemir, Imran; Zuhur, Cigdem; Bayar, Nihal

2010-01-01

102

Proteinosis alveolar pulmonar, caso clínico  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish La Proteinosis Alveolar Pulmonar es una patología poco frecuente, especialmente en la edad pediátrica, caracterizada por acumulación de material lipoproteináceo proveniente del surfactante en los macrófagos alveolares. Objetivo: Comunicar un caso de proteinosis pulmonar en el cual el uso de la fibro [...] broncoscopía (FB) permitió el diagnóstico y el tratamiento. Caso Clínico: Escolar de 7 años, que consulta por un cuadro febril, en la cual se plantea inicialmente el diagnóstico de neumonía. Ante la mala evolución, con aumento de las imágenes radiológicas de tipo nodular, el ascenso de los niveles de LDH en plasma, y la mínima sintomatología clínica respiratoria, se planteó el diagnóstico de proteinosis alveolar, realizando una FB con lavado alveolar. Las tinciones de Sudán y PAS confirmaron la sospecha diagnóstica, lo cual fue apoyado por la mejoría radiológica y clínica de la paciente. Discusión: Se discute las formas clínicas de presentación, los hallazgos clínicos, radiológicos y de laboratorio que permiten plantear el diagnóstico. Se destaca el rol de la fibrobroncoscopía como método diagnóstico y terapéutico Abstract in english Pulmonary Alveolar Proteinosis. Case-report Pulmonary alveolar proteinosis is a rare pathology in children, characterized by the presence of lipoprotein material becoming from surfactants in alveolar macrophages. Objetive: Describe a clinical case of pulmonary proteinosis, in which fibrobronchoscopy [...] (FB) allowed diagnosis and treatment. Case-report: A 7 years-old boy with fever and diagnostic presumption of pneumonia. The evolution was not favorable, in terms of increase in nodular images on chest X-ray and increase in LDH plasmatic level, with few respiratory symptoms. The diagnosis of pulmonary alveolar proteinosis was suspected, performing a FB with bronchoalveolar lavage, where Sudán and PAS colouring confirmed the diagnosis. Discussion: Analysis of clinical presentations, laboratory findings and chest images that suggest the diagnosis. It is important to point out the role of FB in diagnosis and treatment

TERESA, PARAM S; MANUEL, FLORES S; JUAN PABLO, BOLBARAN S; ARMANDO, DÍAZ C; JUAN CARLOS, ACUÑA H; LAURA, OCHOA M.

103

Multiple internal resorption in permanent teeth associated with hyperparathyroidism.  

Science.gov (United States)

Internal resorption has been described as a resorptive defect of internal aspect of tooth. It is caused by transformation of normal pulp tissue into granulomatous tissue with giant cells which resorb dentin. Though mostly idiopathic in origin, trauma, caries and restorative procedures have also been suggested to be contributing factors of internal resorption of pulp. Most of the internal resorption cases were found on isolated individual tooth. There are few case reports on multiple root resorptions. External root resorption have been frequently associated with systemic disorders like renal diseases hyperparathyroidism, rickets etc. A rare association of multiple internal resorption of permanent teeth (including lateral incisors, canines, premolars, sparing 2 nd and 3 rd. Permanent molars and missing 35,36, 42) with elevated levels of PTH and uric acid was evident in a 28 year old female patient who presented with fracture of crowns of permanent teeth. Though many cases related to dental manifestations of chronic renal disease and internal resorption of permanent teeth have been documented in literature, there is no evidence on association of hyperparathyroidism with multiple internal resorptions of teeth. PMID:23852246

Nagaraj, Eswar; Kaur, Roopam Pal; Raghuram, P H; Kumar, P Suresh

2013-01-01

104

Internal root resorption in the maxillary central incisor  

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Full Text Available Introduction: Internal root resorption is a chronic inflammatory process initiated within the pulp space with the loss of dentin. The clastic cells present in the pulp tissue trigger a progressive resorption phenomenon. Case report and conclusion: This paper reports a clinical case of an internal root resorption in the permanent central incisor, at the middle third of the root canal. Because it is asymptomatic,internal root resorption needs an early diagnosis in order to institute the endodontic treatment before the process compromises the mineralized structures of the tooth.

Josué MARTOS

2010-06-01

105

Alveolar mucosa necrosis induced by utilisation of calcium hydroxide as root canal dressing.  

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This case demonstrates the ability of calcium hydroxide to cause connective tissue necrosis. A patient with a history of trauma exhibited a large area of external inflammatory root resorption affecting the cervical and middle thirds of tooth 12. After root canal cleaning, a calcium hydroxide root canal dressing was applied to control the resorption process. After three days when the patient attended for replacement of the dressing an irregular zone of necrosis was observed on the buccal aspect of the alveolar mucosa. Careful curettage and irrigation was then performed to remove the extruded calcium hydroxide and necrotic tissue. After curettage, the root canal was accessed and irrigated with saline solution for removal of remnants of the dressing. The dressing was than replaced taking care to avoid contact with soft tissue, which might induce further damage, minimising the overflow of material. Improvement in healing was observed at 15-day follow-up, with complete closure of the lesion by soft tissue. At the 120-day follow-up, no scar was detected. At 180-day follow-up, the root canal was filled only with mineral trioxide aggregate (MTA) with aid of K files #20 and #50. At two-year follow-up, there were no symptoms and the resorption process seemed to have ceased. It is important to emphasise the damage that may occur when calcium hydroxide is in close and extended contact with the soft tissues, which could happen when dressing material is extruded through a root resorption. PMID:18478888

Bramante, Clóvis Monteiro; Luna-Cruz, Suyane Maria; Sipert, Carla Renata; Bernadineli, Noberti; Garcia, Roberto Brandão; de Moraes, Ivaldo Gomes; de Vasconcelos, Bruno Carvalho

2008-04-01

106

Oral malodor associated with internal resorption.  

Science.gov (United States)

We report a case of oral malodor associated with internal resorption. A 39-year-old male attended our hospital complaining of oral malodor. Utilizing organoleptic measurement, the halimeter test and gas chromatography, it was diagnosed as a strong halitosis caused by oral origin. The pocket probing depth of tooth 21 was 10 mm, and X-ray examination revealed a vertical bone loss around this tooth. The patient had received periodontal treatment at two dental offices previously, but the periodontal conditions and oral malodor persisted. We performed an initial periodontal preparation, however a deep pocket remained. We therefore performed a surgical inspection including flap reflection, and found that the tooth had a large perforating defect in the distal surface. The extracted tooth had multiple perforating defects covered with granulation tissues on all root surfaces including the root apex. Taking into consideration the anamnesis and X-ray examination of the extracted tooth, internal absorption was considered to have been the cause of the multiple perforating defects. After extraction of the causative tooth, oral malodor dramatically decreased. To our knowledge, this is the first report of an oral malodor associated with internal resorption. PMID:16858138

Yoneda, Masahiro; Naito, Toru; Suzuki, Nao; Yoshikane, Toru; Hirofuji, Takao

2006-06-01

107

Replantation of an Avulsed Central Incisor after Long Extra- Alveolar Period. (Case Report  

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Full Text Available A case involving the replantation of an avulsed incisor after long extra-oral period (8 days is reported. After cleaning the root surface, the tooth was soaked in fluoride gel for 20 minutes and root canal therapy was performed extraorally. The tooth was stabilized by wire and composite for six weeks. The patient has been periodically recalled and the tooth monitored for 36 months after replantation. Only minor external surface resorption was observed in the periapical area on the rodiograph, which was taken immediately before removal of the splint and the rate of subsequent replacement resorption has been acceptable. It should be considered that and extended extraoral period is not an absolute contraindication to replantation. Teeth replanted after long extra- alveolar periods can function for a long period of time and thus postpone prosthetic treatment.

Seraj B

2000-05-01

108

Congenital granular cell tumor of the alveolar ridge  

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Full Text Available Congenital epulis or neonatal granular cell tumor is a tumor whose histogenesis has long been debated. It is dissimilar to other granular cell tumors; the latter having derivation from Schwann cells and hence being S-100 positive. We report a case of congenital granular cell tumor in a newborn female child that was uneventfully operated. The case is reported here because of its rarity.

Dhingra Meetu

2010-04-01

109

Biomechanical aspects of external root resorption in orthodontic therapy.  

Science.gov (United States)

External apical root resorption is a common phenomenon associated with orthodontic treatment. The factors relevant to root resorption can be divided into biological and mechanical factors. Some mechanical and biological factors might be associated with an increased or decreased risk of root resorption during orthodontic treatment. For mechanical factors, the extensive tooth movement, root torque and intrusive forces, movement type, orthodontic force magnitude, duration and type of force are involved. For biological factors, a genetic susceptibility, systemic disease, gender and medication intake have been demonstrated influence root resorption. Orthodontic therapy of patients with increased risk of root resorption should be carefully planned. Medical history, medication intake, family history, tooth agenesis, root morphology, oral health and habits must be considerate if we do not want jeopardize our patients by severe root resorption. To monitor apical root resorption the standard procedure is a radiographic examination after 6 months of treatment. In teeth with enhanced risk, a 3-month radiographic follow-up is recommended. The administration of anti-inflammatory drugs might suppress root resorption induced by orthodontic therapy, although none study was enough conclusive to indicate a protocol for patients with enhanced risk. In the event of multiple external root resorption, the diagnostic procedure should focus on the exclusion of the local factors and its associations (such as magnitude, duration and type of orthodontic force; periodontal disease; root form) that might lead to external root resorption. Systemic disorders associated with phosphorus-calcium metabolic alterations shall be suspected. This review searched the current knowledge of the mechanical and biological aspects of root resorption in orthodontic tooth movement. PMID:18059250

Abuabara, Allan

2007-12-01

110

Predicting and preventing root resorption: Part I. Diagnostic factors.  

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The purpose of this study was to determine whether it would be possible to identify pretreatment factors that will allow the clinician to predict the incidence, location, and severity of root resorption before the commencement of orthodontic treatment. The records of 868 patients who were treated with full, fixed edgewise appliances were obtained from 6 private offices; full-mouth periapical radiographs were used to accurately assess apical root resorption from first molar to first molar in both arches. The results showed that resorption occurs primarily in the maxillary anterior teeth, averaging over 1.4 mm. The worst resorption was seen in maxillary lateral incisors and in teeth with abnormal root shape (pipette, pointed, or dilacerated). Adult patients experienced more resorption than children did in the mandibular anterior segment only. Asian patients were found to experience significantly less root resorption than white or Hispanic patients. Increased overjet, but not overbite, was significantly associated with greater root resorption. There was no difference in either the incidence or severity of root resorption between male and female patients. PMID:11343022

Sameshima, G T; Sinclair, P M

2001-05-01

111

Tooth resorption in the Swedish Eurasion lynx (Lynx lynx).  

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The etiology of tooth resorption in the domestic cat remains unknown. The high prevalence and progressive nature of the disease complicates defining healthy control groups. In order to evaluate the possible influence of various life style changes on the prevalence of tooth resorption, healthy control groups are a prerequisite. This paper presents a prevalence study for tooth resorption in a free-ranging wild felidae population. Skulls from 46 free-ranging Eurasian lynx (Lynx lynx) were examined. The age of the animals had previously been estimated based on cementum annuli in the maxillary right canine tooth. The dental examination included both dental probing and radiographic imaging. Complicated fractures of the canine teeth were found in 9/46 (19.5%) skulls. In one fractured canine, apical root resorption and periapical lucency was detected. The root resorption was attributed to inflammatory resorption as a consequence of the initial dental trauma and necrotic pulp. No signs of tooth resorption were found in the remaining teeth. Supernumerary roots were detected in 18/46 skulls (39.1 %). Supernumerary "peg" teeth caudal to the mandibular first molar tooth were detected in 6/46 (13.0%) skulls. Although further studies on dental ultra-structure are needed, the Swedish Eurasian lynx may, in the future, be useful as a healthy comparative model for studies on the etiopathogenesis of tooth resorption in the domestic cat. PMID:21322429

Pettersson, Ann

2010-01-01

112

Endodontic therapy of pathological resorptions of tooth root  

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Full Text Available Pathological resorptions of a tooth root very often represent both a diagnostic and therapeutical problem. The goal of this study was, based on clinical research on a number of pathological resorptions of various types and localization in relation to time, to analyze and evaluate applied endodontic therapy. Clinical research covered 30 patients (40 root canals in total. 18 teeth (22 canal with external and 12 (18 canal with internal root resorptions received endodontic therapy. After standard endodontic procedure had been applied (cleaning and canal shaping calcium hydroxide paste was used as a canal medicament for cases with internal resorptions and calcium hydroxide paste and points for cases with external resorptions. Canal opturations were done by modified technique of lateral condesation applying AH- Plus paste. The obtained results showed that in cases of internal resorption after 12 months, 11 cases were successful and only 1 failure occurred. In case of external resorption, after the same period of time, 15 cases were successful and failures occurred in 3 cases. The success of resorption treatment depends on many factors but, primarily, it depends on time and accuracy of diagnosis and properly applied treatment and root canal opturation.

Opa?i?-Gali? Vanja

2004-01-01

113

Management of internal resorption of central incisor using hybrid technique.  

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Internal inflammatory root resorption is characterised by progressive destruction of intraradicular dentin and dentinal tubules along the root canal wall. A number of theories have been proposed as a possible cause for internal resorption. It is usually asymptomatic and detected during routine radiographic investigations. Prompt diagnosis and early management of such defects is essential to maintain the integrity of the tooth. Non-surgical and surgical methods are the two main strategies involved in the management of internal resorption. The non-surgical method is usually preferred, but in cases of extensive resorption with external root perforation, surgical intervention has been advocated. The present case illustrates repair of perforating internal resorption by hybrid method, using mineral trioxide aggregate and gutta-percha, following surgical exposure. After a 10-month follow-up, no clinical and radiographic abnormalities were observed. Additionally, there was also marked reduction in periodontal pocket depth. PMID:24473420

Gayathri, Prabakaran; Pandey, Ramesh Kumar; Jain, Eesha

2014-01-01

114

Biomechanical aspects of external root resorption in orthodontic therapy  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: English Abstract in english External apical root resorption is a common phenomenon associated with orthodontic treatment. The factors relevant to root resorption can be divided into biological and mechanical factors. Some mechanical and biological factors might be associated with an increased or decreased risk of root resorpti [...] on during orthodontic treatment. For mechanical factors, the extensive tooth movement, root torque and intrusive forces, movement type, orthodontic force magnitude, duration and type of force are involved. For biological factors, a genetic susceptibility, systemic disease, gender and medication intake have been demonstrated influence root resorption. Orthodontic therapy of patients with increased risk of root resorption should be carefully planned. Medical history, medication intake, family history, tooth agenesis, root morphology, oral health and habits must be considerate if we do not want jeopardize our patients by severe root resorption. To monitor apical root resorption the standard procedure is a radiographic examination after 6 months of treatment. In teeth with enhanced risk, a 3-month radiographic follow-up is recommended. The administration of anti-inflammatory drugs might suppress root resorption induced by orthodontic therapy, although none study was enough conclusive to indicate a protocol for patients with enhanced risk. In the event of multiple external root resorption, the diagnostic procedure should focus on the exclusion of the local factors and its associations (such as magnitude, duration and type of orthodontic force; periodontal disease; root form) that might lead to external root resorption. Systemic disorders associated with phosphorus-calcium metabolic alterations shall be suspected. This review searched the current knowledge of the mechanical and biological aspects of root resorption in orthodontic tooth movement.

Allan, Abuabara.

115

Association of type 2 diabetes mellitus with the reduction of mandibular residual ridge among edentulous patients using panoramic radiographs  

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Full Text Available Objective: To evaluate the association between type 2 diabetes mellitus and the reduction of mandibular residual ridge in completely edentulous patients wearing complete dentures and to investigate the ef-fect of gender, age and years of edentulousness / den-ture wearing on ridge resorption on both groups. Methods:Seventy-two (36 men and 36 women with a mean age 63.5 years (range of 52 to 73 years com-pletely edentulous denture-wearing patients were included in this study. Of these, there were 40 patients with type 2 diabetes mellitus and 32 control subjects participated in the study. Resorption in the mandibular residual ridges was assessed by using the mental foramen and the inferior border of the mandible, as they appear in panoramic radiographs, as reference points using Wical and Swoope Analysis method. Measurements were performed using “Dijite” Digital Caliper. The amount of mandibular ridge resorption was calculated and correlated with type 2 diabetes mellitus and the results were compared with control group. Differences in gender, age and years of edentulousness were investigated. Statistical analysis was performed using SPSS (V11.0. A 2-sample t-test was used to evaluate the differences in mean values of mandibular ridge resorption between diabetics and controls. Level of significance was set at 0.05. Results: The mean mandibular residual ridge resorption of all participants is 8.0 mm (26.9%, diabetic group significantly (P < 0.01 had two times more resorption compared with control group (35.8% versus 18.0%. Females recorded greater amount of resorption in diabetics 49.7% versus 21.8% (P < 0.001 and in controls 22.3% versus 13.7%, (P < 0.05 compared to males, respectively. There were no differences in both groups regarding the age of subjects and the length of time they have been edentulous and years of denture wearing. The amount of mandibular residual ridge resorption was directly related to the number of years of edentulousness. Conclusion: Completely edentulous, denture-wearing diabetics, women in particular, are at more risk to have ridge resorption than “nondiabetic” subjects. Reduced mandibular height is directly related to years of edentulousness and denture wear-ing with greater amount of resorption among diabet-ics.

Osama Al-Jabrah

2011-09-01

116

Pulmonary alveolar microlithiasis with calcified pleural plaques  

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Pulmonary alveolar microlithiasis (PAM) is a rare disease. Herein we report a case of pulmonary alveolar microlithiasis who was suspected to have the disease on chest X-ray and was confirmed on high resolution CT and transbronchial lung biopsy. These investigations showed characteristic features of pulmonary alveolar microlithiasis with diffuse interstitial pulmonary fibrosis. PMID:21139727

Malhotra, Balbir; Sabharwal, Raghu; Singh, Mandeep; Singh, Amarjeet

2010-01-01

117

Central osteoma associated with root resorption.  

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Osteomas of the jaws are rare osteogenic lesions considered to be true neoplasms, characterized by the proliferation of compact and/or cancellous bone. It can be central, peripheral, or of an extraskeletal type. The central osteoma arises from the endosteum, the peripheral osteoma from the periosteum, and the extraskeletal soft tissue osteoma usually develops within a muscle. However, in a previous work we have suggested that at least some peripheral osteomas may be reactive rather than neoplasms, probably associated with trauma. Some reported cases did have a clear history of trauma; however, this was not the case in the majority of cases. Whereas peripheral osteomas are fairly easy to diagnose, central osteomas pose a more challenging diagnostic problem and need to be differentiated from other similar lesions of the jaws, such as central ossifying fibroma, condensing osteitis, idiopathic osteosclerosis, osteoblastoma, cementoblastoma, and complex odontoma. With such a low number of case of central osteoma reported, the objectives of the present report are to describe a case of the central osteoma associated with partially root resorption of the mandibular first molar. Our case report participates to literature as a 11th case. PMID:20216457

Bulut, Emel; Ozan, Bora; Günhan, Omer

2010-03-01

118

Multiple Idiopathic Apical Root Resorption: a Case Report  

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Full Text Available The aim of this case report was to present a case of multiple idiopathic apical root resorption which is a rare condition in a 17-year-old adult male. External root resorption of the permanent teeth is a multifactorial process. Well-recognized causes of apical rootresorption in permanent teeth include orthodontic therapy, trauma, periapical or periodontal inflammation, tumors, cysts, occlusal stress, impacted teeth, systemic conditions, endocrine imbalances and dietary habits. When none of these causes are present, it is termed idiopathic root resorption which may be either cervical or apical.Multiple idiopathic apical root resorption is a rare condition which is usually detected as an incidental radiographic finding. However, it may cause pain and mobility in severe cases.

L. Khojastepour

2010-09-01

119

[Root resorption. 1. Etiopathogenesis, diagnosis and clinical manifestations].  

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The authors, after having thoroughly reviewed the literature regarding all types of root resorption, specifically investigated those of clear endodontic pertinence, and evaluated the etiopathogenesis, the possibility of diagnosis, and the clinical incidence. PMID:1782440

Gorni, F; Lamorgese, V; Malentacca, A

1991-01-01

120

Clinical Study Comparing Alveolar Distraction Using the Lead System and MODUS MDO 1.5/2.0.  

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This article compares 2 different alveolar distractors: Lead System (LS) and MODUS MDO 1.5/2.0 (M-MDO). This is a clinical retrospective study; 32 distractions were performed. We used the LS distractor (intraosseous) on 24 patients and the M-MDO (extraosseous) on the other 8. The variables included bone alveolar ridge height, alterations of the oral mucosa, number of distractors, implant survival, and complications. We also developed descriptive and univariate statistical analysis. The mean increase of bone height after performing the alveolar distraction was 6.15 mm, 5.74 mm with LS, and 8.36 mm with M-MDO (P LS (P LS and the M-MDO distractors are effective for alveolar bone distraction. The choice of one distractor over another depends on the clinical characteristics of each case, such as the size and shape of the defect, the patient's tolerance, the distance to the opposing arch, and the surgeon's experience. PMID:25376144

Pérez-Sayáns, Mario; Martins-Horta, Dina; Somoza-Martin, Manuel; Fernández-González, Beatriz; Reboiras-López, Dolores; Vila, Pilar Gándara; García García, Abel

2014-11-01

 
 
 
 
121

Inflammatory root resorption in primary molars: prevalence and associated factors  

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Full Text Available This study aimed at determining the prevalence of inflammatory root resorption and associated factors in 1068 primary mandibular molars in 453 children 3 to 12 years of age. Age, dental history and medical history were recorded using a questionnaire administered to the children's parents/caregivers. Previously trained and calibrated examiners assessed radiographic images of the primary molars by direct observation, with the aid of a viewing box. Root resorption (physiological or inflammatory, dental crown status (healthy, carious with no pulp involvement, carious with pulp involvement and evidence of restoration, and pulpotomy or pulpectomy were determined. Data analysis involved descriptive statistics, the chi-square test and a multiple logistic regression (p < 0.05. The prevalence of inflammatory root resorption was 16.2% (n = 173. The male gender (OR: 1.4; 95% CI, the 3-to-7-years age bracket (OR: 1.5; 95% CI, an unhealthy dental crown (OR: 8.7; 95% CI, caries with pulp involvement (OR: 7.4; 95% CI, pulpotomy (OR: 3.1; 95% CI, and pulpectomy (OR: 5.4; 95% CI were risk factors for the occurrence of inflammatory root resorption in primary molars. In conclusion, the prevalence of inflammatory root resorption in the present sample was 16.2%. Gender, age, an unhealthy tooth, caries with pulp involvement, pulpotomy, pulpectomy, and the absence of a restoration were associated with a higher occurrence of inflammatory root resorption in primary molars.

Raquel Gonçalves Vieira-Andrade

2012-08-01

122

Distribution of BMP6 in the alveolar bone during mouse mandibular molar eruption.  

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Abstract Eruption requires synchrony of the tooth with the surrounding tissues, particularly the bone. One important step during eruption is remodelling of the alveolar bone at the base of the tooth and along the roots. Expression of BMP6 was reported to be increased in the basal half of the dental follicle prior to eruption and inhibition of BMP6 affected bone formation at the base of the alveolar crypt. The aim of this study was to further investigate BMP6 protein in relation to tooth eruption and the corresponding bone remodelling using temporospatial correlations of BMP6 localization with morphogenetic events (proliferation, differentiation, apoptosis and bone apposition/resorption), other BMPs (BMP2 and BMP7) and three-dimensional images of tooth-bone development. BMP6 expression pattern was mapped in the mandibular molar teeth and related structures around eruption. Localization of BMP6 dominated in osteoblasts, in regions of bone formation within the alveolar crypt. These findings positively correlated with proliferation at the tooth base region, osteocalcin expression in the osteoblasts/osteocytes and BMP2 and BMP7 presence in the alveolar bone surrounding the tooth. Osteoclast activity and apoptotic elimination in the root region gradually decreased before eruption and totally ceased at eruption stages. Generally, BMP6 positively correlated with BMP2, BMP7 and osteocalcin-positive osteoblasts, and areas of bone remodelling. Moreover, BMP6 was found in the periodontium and cementoblasts. BMP6 expression in the alveolar bone accompanied tooth eruption. Notably, the expression pattern of BMP6 in the bone did not differ around individual molar teeth at the same stage of development. The expression of BMP6 in periodontal ligaments may contribute to interaction between the tooth and bone during the eruption and anchoring process. PMID:25084210

Oralová, Veronika; Chlastáková, Ivana; Radlanski, Ralf Johannes; Matalová, Eva

2014-10-01

123

Alveolar septal pulmonary amyloidosis: a case report  

International Nuclear Information System (INIS)

Primary pulmonary amyloidosis is a rare diesase, and is classified as either tracheobronchial or parenchymal; the latter is also divided into nodular and diffuse alveolar septal forms. The alveolar septal form is extremely rare and usually produces reticular and nodular opacities. We describe a case of alveolar septal pulmonary amyloidosis manifested as multiple small nodules on chest radiograph and disseminated micronodules mainly in centrilobular and subpleural location without reticular opacities, on HRCT

124

Rac-null leukocytes are associated with increased inflammation-mediated alveolar bone loss.  

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Periodontitis is characterized by altered host-biofilm interactions that result in irreversible inflammation-mediated alveolar bone loss. Genetic and epigenetic factors that predispose to ineffective control of biofilm composition and maintenance of tissue homeostasis are not fully understood. We elucidated how leukocytes affect the course of periodontitis in Rac-null mice. Mouse models of acute gingivitis and periodontitis were used to assess the early inflammatory response and patterns of chronicity leading to loss of alveolar bone due to inflammation in Rac-null mice. Leukocyte margination was differentially impaired in these mice during attachment in conditional Rac1-null (granulocyte/monocyte lineage) mice and during rolling and attachment in Rac2-null (all blood cells) mice. Inflammatory responses to subgingival ligatures, assessed by changes in peripheral blood differential leukocyte numbers, were altered in Rac-null compared with wild-type mice. In response to persistent subgingival ligature-mediated challenge, Rac-null mice had increased loss of alveolar bone with patterns of resorption characteristic of aggressive forms of periodontitis. These findings were partially explained by higher osteoclastic coverage of the bone-periodontal ligament interface in Rac-null compared with wild-type mice. In conclusion, this study demonstrates that leukocyte defects, such as decreased endothelial margination and tissue recruitment, are rate-limiting steps in the periodontal inflammatory process that lead to more aggressive forms of periodontitis. PMID:24269593

Sima, Corneliu; Gastfreund, Shoshi; Sun, Chunxiang; Glogauer, Michael

2014-02-01

125

The effect of photobiomodulation on root resorption during orthodontic treatment  

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Full Text Available Ghada Nimeri, Chung H Kau, Rachel Corona, Jeffery Shelly Department of Orthodontics, University of Alabama, Birmingham, AL, USA Abstract: Photobiomodulation is used to accelerate tooth movement during orthodontic treatments. The changes in root morphology in a group of orthodontic patients who received photobiomodulation were evaluated using the cone beam computed tomography technique. The device used is called OrthoPulse, which produces low levels of light with a near infrared wavelength of 850 nm and an intensity of 60 mW/cm2 continuous wave. Twenty orthodontic patients were recruited for these experiments, all with class 1 malocclusion and with Little's Irregularity Index (>2 mm in either of the arches. Root resorption was detected by measuring changes in tooth length using cone beam computed tomography. These changes were measured before the orthodontic treatment and use of low-level laser therapy and after finishing the alignment level. Little's Irregularity Index for all the patients was calculated in both the maxilla and mandible and patients were divided into three groups for further analysis, which were then compared to the root resorption measurements. Our results showed that photobiomodulation did not cause root resorption greater than the normal range that is commonly detected in orthodontic treatments. Furthermore, no correlation between Little's Irregularity Index and root resorption was detected. Keywords: photobiomodulation, root resorption, accelerate tooth movement, orthodontics, cone beam computed tomography

Nimeri G

2014-01-01

126

Radio-opaque agents in bone cement increase bone resorption.  

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A heavy infiltrate of foreign-body macrophages is commonly seen in the fibrous membrane which surrounds an aseptically loose cemented implant. This is in response to particles of polymethylmethacrylate (PMMA) bone cement and other biomaterials. We have previously shown that monocytes and macrophages responding to particles of bone cement are capable of differentiating into osteoclastic cells which resorb bone. To determine whether the radio-opaque additives barium sulphate (BaSO4) and zirconium dioxide (ZrO2) influence this process, particles of PMMA with and without these agents were added to mouse monocytes and cocultured with osteoblast-like cells on bone slices. Osteoclast differentiation, as shown by the presence of the osteoclast-associated enzyme tartrate-resistant acid phosphatase (TRAP) and lacunar bone resorption, was observed in all cocultures. The addition of PMMA alone to these cocultures caused no increase in TRAP expression or bone resorption relative to control cocultures. Adding PMMA particles containing BaSO4 or ZrO2, however, caused an increase in TRAP expression and a highly significant increase in bone resorption. Particles containing BaSO4 were associated with 50% more bone resorption than those containing ZrO2. Our results suggest that radio-opaque agents in bone cement may contribute to the bone resorption of aseptic loosening by enhancing macrophage-osteoclast differentiation, and that PMMA containing BaSO4 is likely to be associated with more osteolysis than that containing ZrO2. PMID:9020461

Sabokbar, A; Fujikawa, Y; Murray, D W; Athanasou, N A

1997-01-01

127

Spontaneous resorption of a large cervical herniated nucleus pulposus.  

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The majority of patients with symptomatic herniated discs can be successfully and conservatively managed and can achieve clinical improvement without surgical intervention. Resorption of the herniated nucleus pulposus (HNP) is 1 conservative mechanism for clinical improvement. We present the case of a 76-year-old healthy man with acute cervical radicular right arm pain and positive Spurling test. Magnetic resonance imaging (MRI) showed a large disc extrusion behind the C6 vertebral body, causing severe central canal stenosis and right-greater-than-left foraminal stenosis. The patient did not want surgical intervention, and his symptoms resolved with conservative treatment. A follow-up MRI 7 months after his initial presentation showed almost complete resorption of the herniated disc. The patient returned to his normal activities and has not had recurrence of symptoms for 2 years. This report provides an interesting example of complete resorption of a large, extruded cervical herniated disc in a symptomatic patient and a review of the literature on resorption of herniated discs. The review suggests that larger herniations with an epidural location (penetration of the posterior longitudinal ligament) have a greater chance of resorption. PMID:25046190

Cvetanovich, Gregory L; Hsu, Andrew R; Frank, Rachel M; An, Howard S; Andersson, Gunnar B

2014-07-01

128

Osteoporosis: the effect on maxillary bone resorption and therapeutic possibilities by means of implant prostheses--a literature review and clinical considerations.  

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Osteoporosis is a systemic disease in which the skeletal condition is characterized by a decreased mass of normally mineralized bone. It is considered the most common metabolic bone disease, and it constitutes a major public health problem. Given the evidence that alveolar processes provide the bony framework for tooth support, the decline of skeletal mass has to be correlated with an increased risk of oral bone loss and has a negative consequence on tooth stability. Data from past research confirm that aging and estrogen depletion have a negative influence on both tooth retention and residual alveolar crest preservation. The goal of the present article is, however, to underline how the morphostructural evolution of the edentulous maxilla is mainly due to mechanical factors as the result of alterations in maxillary function. The advantages of prosthetic rehabilitation supported by osseointegrated implants are also considered, focusing the therapeutic role of this procedure on preserving the residual alveolar ridge from atrophy. PMID:14620119

Sanfilippo, Francesco; Bianchi, Andrea E

2003-10-01

129

Effects of a Mikania laevigata extract on bone resorption and RANKL expression during experimental periodontitis in rats  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVES: The Mikania laevigata extract (MLE) (popularly known in Brazil as "guaco") possesses anti-inflammatory properties. In the present study we tested the effects of MLE in a periodontitis experimental model in rats. We also investigated possible mechanisms underlying such effects. MATERIAL A [...] ND METHODS: Periodontal disease was induced by a ligature placed around the mandibular first molars of each animal. Male Wistar rats were divided into 4 groups: non-ligated animals treated with vehicle; non-ligated animals treated with MLE (10 mg/kg, daily); ligature-induced animals treated with vehicle and ligature-induced animals treated with MLE (10 mg/kg, daily). Thirty days after the induction of periodontal disease, the animals were euthanized and mandibles and gingival tissues removed for further analysis. RESULTS: Morphometric analysis of alveolar bone loss demonstrated that MLE-treated animals presented a decreased alveolar bone loss and a lower expression of the activator of nuclear factor-?B ligand (RANKL) measured by immunohistochemistry. Moreover, gingival tissues from the MLE-treated group showed decreased neutrophil migration myeloperoxidase (MPO) assay. CONCLUSIONS: These results indicate that MLE may be useful to control bone resorption during progression of experimental periodontitis in rats.

Bruno B., Benatti; Jozafá C., Campos-Júnior; Vilmar J., Silva-Filho; Polyanna M., Alves; Isabela R., Rodrigues; Elizabeth, Uber-Bucek; Silvio M., Vieira; Marcelo H., Napimoga.

2012-06-01

130

[Current topics in drug therapy aiming at bone resorption].  

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The majority of current therapeutics for osteoporosis is targeting bone resorption by osteoclasts. Bisphosphonates, potent and specific inhibitors of bone resorption, are widely used for postmenopausal osteoporosis on the basis of large scale clinical trials which proved their ability to reduce fracture risk. Estrogen, which had been widely used in the US, lost its position of standard drug therapy for osteoporosis because of the recent evidence of increasing adverse events. On the other hand, the market share of selective estrogen-receptor modulators (SERMs), which utilize valuable functions of estrogen and have less adverse effects, has been climbing. Other novel therapeutic agents which aim at signal transduction of osteoclast differentiation and activation are promising as specific inhibitors of bone resorption. PMID:16951471

Yasui, Tetsuro; Tanaka, Sakae

2006-09-01

131

NOD2 Contributes to Porphyromonas gingivalis-induced Bone Resorption.  

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The NOD-like receptors are cytoplasmic proteins that sense microbial by-products released by invasive bacteria. Although NOD1 and NOD2 are functionally expressed in cells from oral tissues and play a role triggering immune responses, the role of NOD2 receptor in the bone resorption and in the modulation of osteoclastogenesis is still unclear. We show that in an experimental model of periodontitis with Porphyromonas gingivalis W83, NOD2(-/-) mice showed lower bone resorption when compared to wild type. Quantitative polymerase chain reaction analysis revealed that wild-type infected mice showed an elevated RANKL/OPG ratio when compared to NOD2(-/-) infected mice. Moreover, the expression of 2 osteoclast activity markers-cathepsin K and matrix metalloproteinase 9-was significantly lower in gingival tissue from NOD2(-/-) infected mice compared to WT infected ones. The in vitro study reported an increase in the expression of the NOD2 receptor 24 hr after stimulation of hematopoietic bone marrow cells with M-CSF and RANKL. We also evaluated the effect of direct activation of NOD2 receptor on osteoclastogenesis, by the activation of this receptor in preosteoclasts culture, with different concentrations of muramyl dipeptide. The results show no difference in the number of TRAP-positive cells. Although it did not alter the osteoclasts differentiation, the activation of NOD2 receptor led to a significant increase of cathepsin K expression. We confirm that this enzyme was active, since the osteoclasts resorption capacity was enhanced by muramyl dipeptide stimulation, evaluated in osteoassay plate. These results show that the lack of NOD2 receptor impairs the bone resorption, suggesting that NOD2 receptor could contribute to the progression of bone resorption in experimental model of periodontitis. The stimulation of NOD2 by its agonist, muramyl dipeptide, did not affect osteoclastogenesis, but it does favor the bone resorption capacity identified by increased osteoclast activity. PMID:25239844

Prates, T P; Taira, T M; Holanda, M C; Bignardi, L A; Salvador, S L; Zamboni, D S; Cunha, F Q; Fukada, S Y

2014-11-01

132

Intracranial alveolar echinococcosis: CT and MRI  

International Nuclear Information System (INIS)

Intracranial alveolar echinococcosis is uncommon. We report a patient with right frontal lobe and palpebral lesions secondary to a primary hepatic focus with secondary lesion in the lung. The intracranial and palpebral cystic masses were totally removed and both proved to be alveolar hydatid cysts. An unusual feature in this case is CT and MRI demonstration of dural and bony extension. (orig.)

133

Effect of fish oil on lipopolysaccharide-induced hydroxyapatite loss in rat alveolar bone: A Preliminary Study  

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Full Text Available Dietary fish oil has been shown to inhibit bone resorption and, therefore, the aim of the present study was to test the hypothesis that fish oil alters lipopolysaccharide (LPS-induced hydroxyapatite loss in rat alveolar bone. Rats were divided into four groups. The animals injected with saline or Escherichia coli-derived LPS into the maxillary alveolar mucosa on the buccoapical site of the molar region daily for 8 days were served as a negative or positive control, respectively. Other groups of animals were injected with LPS and orally treated with fish oil at the same day with or after LPS injection. The results of the present study showed that the hydroxyapatite contents of alveolar bone in rats treated with fish oil at the same day with or before LPS injection were significantly higher than those in rats injected with LPS alone, but still lower than those in untreated animals. Therefore, the present study suggests that oral treatment with fish oil may reduce LPS-induced hydroxyapatite loss in rat alveolar bone

Didin E. Indahyani

2009-02-01

134

Pulmonary alveolar microlithiasis in children  

International Nuclear Information System (INIS)

Two asymptomatic Turkish sibs are presented, a 4-year-old boy and his 7-year-old sister, with pulmonary alveolar microlithiasis (PAM) confirmed by transbronchial lung biopsy and bronchoalveolar lavage. Chest radiographs and high resolution CT demonstrated wide-spread intra-alveolar calcifications in both lungs. The lesions were sharply defined and less than 1 mm in diameter. CT documented a high concentration of microliths along the bronchovascular bundles, the intralobular fissue and the (sub)pleural lung parenchyma. The combination of bronchoalveolar lavage and roentgenographic appearance in high resolution CT are characteristic and pathognomonic, and can confirm the diagnosis. The more severe changes in the elder sib and the radiographic controls suggest that the pulmonary disease may be progressive in our patients. The described family of consanguineous, unaffected parents with two affected and one healthy child confirmed the autosomal recessive inheritance of PAM (McKusick 265100). In addition, the affected girl had autosomal recessive Waardenburg-anophthalmia syndrome (McKusick 206920), raising the question of whether this is a chance occurrence or possibly a contiguous gene syndrome. (orig.)

135

CT features of lung alveolar echinococcosis  

International Nuclear Information System (INIS)

Objective: To analyze the CT features of lung alveolar echinococcosis and assess the value of CT scanning for the diagnosis of this disease. Methods: The CT features of lung alveolar echinococcosis in 26 patients diagnosed pathologically or clinically were reviewed retrospectively and correlated with histopathology. Results: Lung alveolar echinococcosis appeared as multiple lesions bilaterally in 18 patients, as multiple lesions unilaterally in 6 patients, and as single lesion bilaterally in 2 patients. Seventeen cases presented as masses and nodules, 8 patients presented as nodules, 1 patient presented as a mass. Lobulation and speculation were showed in most lesions, irregular cavity or bubble-like opacity in 13 patients,calcification in 18 patients, a patchy area or fibrotic cord around lesion in 14 patients. Pleural thickening adjacent to the lesion in 20 patients. Conclusion: Lung alveolar echinococcosis has characteristic features on CT, and CT can provide important information for the diagnosis of lung alveolar echinococcosis. (authors)

136

Treatment of invasive cervical resorption with sandwich technique using mineral trioxide aggregate: a case report.  

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This article presents two cases of large invasive cervical resorption (ICR) with maintenance of pulp vitality after treatment with mineral trioxide aggregate (MTA) in a sandwich technique.Invasive cervical resorption is a relatively uncommon but aggressive form of external resorption, primarily caused by dental trauma or injury of the cervical periodontal attachment. The resorptive process does not penetrate into the root canal, and the pulp is not involved in the first phase of the resorption. This feature differentiates external resorption from internal resorption. In most cases, invasive cervical resorption is found during routine radiographic or clinical examination. Different materials have been proposed for the treatment of external cervical resorption. Therapy can be effective when it 1) removes the etiological factors and 2) interrupts the progressive resorption mechanism.The key learning points of this article are the following: treatment strategy to arrest the cervical resorption process and to prevent further resorption without changing pulpal vitality and successful seal of invasive cervical resorption defect using MTA with a sandwich technique. PMID:21942289

Kqiku, L; Ebeleseder, K A; Glockner, K

2012-01-01

137

The effect of photobiomodulation on root resorption during orthodontic treatment  

Science.gov (United States)

Photobiomodulation is used to accelerate tooth movement during orthodontic treatments. The changes in root morphology in a group of orthodontic patients who received photobiomodulation were evaluated using the cone beam computed tomography technique. The device used is called OrthoPulse, which produces low levels of light with a near infrared wavelength of 850 nm and an intensity of 60 mW/cm2 continuous wave. Twenty orthodontic patients were recruited for these experiments, all with class 1 malocclusion and with Little’s Irregularity Index (>2 mm) in either of the arches. Root resorption was detected by measuring changes in tooth length using cone beam computed tomography. These changes were measured before the orthodontic treatment and use of low-level laser therapy and after finishing the alignment level. Little’s Irregularity Index for all the patients was calculated in both the maxilla and mandible and patients were divided into three groups for further analysis, which were then compared to the root resorption measurements. Our results showed that photobiomodulation did not cause root resorption greater than the normal range that is commonly detected in orthodontic treatments. Furthermore, no correlation between Little’s Irregularity Index and root resorption was detected. PMID:24470774

Nimeri, Ghada; Kau, Chung H; Corona, Rachel; Shelly, Jeffery

2014-01-01

138

Surgical intervention for treating an extensive internal resorption with unfavorable crown-to-root ratio  

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Internal resorption is a rare lesion in permanent teeth. Managing perforating internal resorption is a great challenge for dentists. This report presents a successful surgical treatment of a maxillary central incisor that had extensive root perforation due to internal resorption. After unsuccessful nonsurgical approach, during surgical intervention apical part of the resorption defect was removed and the coronal part was filled with mineral trioxide aggregate. Three years later the tooth was ...

Ashouri, Rezvan; Rekabi, Ali R.; Parirokh, Masoud

2012-01-01

139

Identification of A Novel Root Resorptive Function of Osteopontin Gene  

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Full Text Available Objective: Osteopontin (OPN has been proposed to play a role in bone resorption. With regard to bone and cementum/dentin structural and histological similarities, it was hy-pothesized that expression of this gene might be increased in resorptive lacunae during orthodontic tooth movement.Materials and Methods: Fixed Nickel-Titanium closed coil springs (Dentaurum® capa-ble of delivering approximately 60 gf were applied for mesial movement of maxillary left first molars in 26 male 8-week-old Wistar rats. The right maxillary molar served as inter-nal control for each subject. After 21 days, the rats were sacrificed. Tissues from 13 rats were examined by histomorphometric analysis and the scratched material from resorptive lacunae on mesial sides of the roots was used for extracting messenger ribonucleic acid (mRNA in RT-PCR reactions. T-test and Wilcoxon signed-rank test served for statistical analyses.Results: Histomorphometric analysis of histologic sections revealed an increased resorbed area in test group compared to control animals (P<0.001. The integrity of mRNA con-firmed by RT-PCR for housekeeping gene glyceraldehyde 3-phosphate dehydrogenase (GAPDH. Densitometric analysis of OPN mRNA on electrophoresis gel showed an in-crease in background levels of OPN in resorptive lacunae of test group (P<0.001.Conclusion: Data indicates that in the controlled environment of this study, an increase in OPN expression is associated with root resorption induced by orthodontic tooth move-ment.

M. Seifi

2008-12-01

140

Evaluation of intracerebral hematoma resorption dynamics with computed tomography  

International Nuclear Information System (INIS)

High mortality and severe grade of disability observed in patients after intracerebral hemorrhage provide efforts to improve diagnostics and therapy of the hemorrhagic cerebral stroke. An aim of this paper was an evaluation of blood resorption dynamics in patients with intracerebral hematoma, performed with computed tomography of the head and an analysis of clinical significance of this process. An examined group included 133 patients with intracerebral hematoma proven by a CT exam. In 97 patients resorption of the hematoma was measured, based on control scans taken on 15th and 30th day on average. Volume of the hemorrhagic foci was measured as well as the width of ventricles and the displacement of medial structures. The mean hematoma volume reached 11,59 ml after 15 days, and 3,16 m after 30 days (average decrease of the volume 0,67 ml/day). There was a significant difference in the rate of resorption between the first (0-15 days) and the second (15-30 days) observation period - 0,78 and 0,62 ml/day respectively. The dynamics of the process was dependent on volume and localization of the hematoma and independent of the grade of displacement and compression of the ventricles. The calculated mean rate of the hematomas resorption enables to schedule control examinations precisely. The significant differences of the dynamics of blood resorption depending on hematomas size and the independence of compression and displacement of ventricular system su and displacement of ventricular system suggest, that the most important factor in therapeutic decision-making should be a clinical status of the patient. (author)

 
 
 
 
141

Geometría de los perfiles alveolares  

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Full Text Available The most common castellated profiles series are established from a reduced set of templates to cut the original profiles. This means that no consideration is given to some parameters that could improve the beam strength behavior obtained from the same profile. In this paper the influence of some of these parameters are studied and some easy to use charts are given for simple beams with uniform load.

Las series de perfiles alveolares, usualmente utilizadas, se establecen a partir de un conjunto reducido de plantillas/patrón para realizar el corte del perfil original, cuya utilización sistemática equivale a no considerar la influencia de algunos parámetros que podrían mejorar el comportamiento resistente de la viga alveolada obtenida a partir del mismo perfil original. En este trabajo se analiza la influencia de algunos de estos parámetros, y se obtienen gráficas de fácil aplicación para el caso de vigas bi apoyad as con carga uniformemente repartida.

Monfort Lleonart, José

1988-10-01

142

Implant supported prosthesis after ridge augmentation procedure by distraction osteogenesis for atrophic mandible.  

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Rehabilitation of deficient alveolar ridges has long been a challenge. The distraction osteogenesis procedure before placement of dental implants has solved the puzzle and its advantages over block grafting includes simultaneous expansion of soft tissue, high degree of dimensional stability, abbreviated overall treatment time, and no graft required. In this case report distraction osteogenesis of deficient anterior mandibular ridge was performed and then an implant supported fixed prosthesis was fabricated. PMID:24431801

Khongshei, Arlingstone; Banerjee, Saurav; Gupta, Tapas; Banerjee, Ardhendu

2013-12-01

143

Evaluation of the posterior superior alveolar artery and the maxillary sinus with CBCT  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Assessment of the maxillary sinus anatomy before sinus augmentation is important for avoiding surgical complications, because of the close anatomical relationship between the posterior maxillary teeth and the maxillary sinus. The posterior superior alveolar artery (PSAA) is the branch of the maxilla [...] ry artery that supplies the lateral sinus wall and overlying membrane. We evaluated the location of the PSAA and its relationship to the alveolar ridge and maxillary sinus using cone beam computed tomography (CBCT). The study group consisted of 135 CBCT scans (270 sinuses) obtained from the archive of the dentomaxillofacial radiology department at Yeditepe University Faculty of Dentistry, Istanbul, Turkey. The distance between the lower border of the artery and the alveolar crest, bone height from the sinus floor to the ridge crest, distance from the artery to the medial sinus wall, and the diameter and location of the artery were determined. The occurrence of septa and pathology were recorded from CBCT scans. The PSAA was observed in 89.3% of sinuses, and 71.1% of arteries were intraosseous with diameters mostly

Dilhan, Ilguy; Mehmet, Ilguy; Semanur, Dolekoglu; Erdogan, Fisekcioglu.

2013-09-01

144

A case of pulmonary alveolar microlithiasis  

International Nuclear Information System (INIS)

A case of pulmonary alveolar microlithiasis is reported. A 33-year-old male visited our clinic because of cough and sore throat. The chest X-ray showed granular micronodulation diffusely disseminated throughout the lung fields. On the eighth day since admission, cough and sore throat disappeared. Pulmonary alveolar microlithiasis was confirmed by transbronchial lung biopsy. Bronchoalveolar lavage (BAL) was performed, and the differential cell count of the BAL fluid showed 74.3 % eosinophilia. Furthermore, 67Ga-citrate scintigraphy revealed diffuse uptake throughout the lung fields. Whether these findings are common in pulmonary alveolar microlithiasis or not is considered to be an unanswered problem. (author)

145

Fluoride effect on the process of alveolar bone repair in rats: evaluation of activity of MMP-2 and 9  

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Full Text Available Objective: The aim of this study was to evaluate comparatively the effect of fluoride (F on the activity of matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9 involved in process of alveolar bone repair. Material and methods: This study used 4 groups of Wistar rats with 80 days of life (n = 160 which received drinking water containing different doses of fluoride (NaF: 5, 15, 50 ppm and deionized water (control throughout the experiment. These animals had their right upper incisors extracted. After extraction, the animals were euthanized at 7, 14, 21 and 30 days and the hemi-maxillae were collected for microscopic analysis (Hematoxylin and Eosin and immunohistochemistry for MMP-9 and zymography (MMP-2 and 9. Results: Microscopically the process of bone repair was similar in all groups, being noted only a delay of the blood clot resorption and bone formation in the group of 50 ppm F. The expression for MMP-9 showed differences between groups only during the initial repair (7 days. However, the zymography showed no significant differences between treated and control groups. Conclusion: Ours results suggest an effect of fluoride on the activity of MMPs 2 and 9 at the initial period of alveolar repair which could be associated to the process of blood clot remission and delay in bone repair. Further studies are needed to establish the relationship between the initial process of resorption of the blood clot, and the involvement of MMPs 2 and 9 and its regulators/tissue inhibitors.

Mileni da Silva Fernandes

2012-09-01

146

Age-dependent changes in porcine alveolar macrophage function during the postnatal period of alveolarization  

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During early postnatal ontogeny in most mammals, the lung is structurally and functionally immature. In some species with relatively altricial lung morphology, there is evidence of a coupling between functional maturity of the pulmonary cellular immune system and alveolar maturation. Herein, we examine changes in alveolar macrophage (AM) number and function occurring during alveolarization in a more precocial species, the pig, to determine if heightened oxidative metabolism and phagocytic abi...

Dickie, R.; Tasat, D. R.; Fernandez Alanis, E.; Delfosse, V.; Tsuda, A.

2009-01-01

147

Seasonal Variation of Nutrient Resorption in Nine Canopy Trees of a Wet Tropical Forest  

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Withdrawal of nutrients at the time of leaf abscission (nutrient resorption) is a nutrient conserving mechanism that could play an important role in stand-level nutrient economy. Currently data on nutrient resorption in wet tropical forests and on how this process varies temporally are sparse. We evaluated the N and P resorption efficiency of nine rain forest canopy tree species in both wet and dry season months. In addition, we measured short-term (bi-weekly) variation in nutrient resorption in the two dominant tree species, Pentaclethra macroloba and Laetia procera, over a 4-month period. We hypothesized that nutrient resorption would be more efficient during the dry season months and that resorption would be low during periods of high rainfall. Contrary to expectations, P resorption efficiency was higher in the wet season for four of the nine canopy tree species, while N resorption did not differ seasonally. The low dry season P resorption efficiency found in this study may be the result of drought stress during short periods of low rainfall, leading to incomplete nutrient resorption from senescing leaves. Nutrient resorption also varied significantly over the short-term. Both P and N resorption efficiency increased in P. macroloba and L. procera as the wet season progressed. The variability in resorption was not related to rainfall or temperature. Instead, the senesced leaf concentrations were a simple proportion of green leaf nutrient concentrations, with short punctuated periods of high resorption efficiency that may be reflective of species-specific phenological events, such as fruit and leaf production. The different timing of the seasonal increase in nutrient resorption between L. procera and P. macroloba supports this hypothesis, deserving of further study.

Wood, T. E.; Lawrence, D.

2006-12-01

148

Disseminated intracerebral alveolar echinococcosis: CT and MRI  

International Nuclear Information System (INIS)

Cerebral alveolar echinococcosis is rare and has a poor prognosis. We report an unusual case presenting with disseminated intracranial lesions secondary to primary hepatic infection. (orig.). With 3 figs

149

Patterns in foliar nutrient resorption stoichiometry at multiple scales: controlling factors and ecosystem consequences (Invited)  

Science.gov (United States)

During leaf senescence, nutrient rich compounds are transported to other parts of the plant and this 'resorption' recycles nutrients for future growth, reducing losses of potentially limiting nutrients. Variations in leaf chemistry resulting from nutrient resorption also directly affect litter quality, in turn, regulating decomposition rates and soil nutrient availability. Here we investigated stoichiometric patterns of nitrogen (N) and phosphorus (P) resorption efficiency at multiple spatial scales. First, we assembled a global database to explore nutrient resorption among and within biomes and to examine potential relationships between resorption stoichiometry and ecosystem nutrient status. Next, we used a forest regeneration chronosequence in Brazil to assess how resorption stoichiometry linked with a suite of other nutrient cycling measures and with ideas of how nutrient limitation may change over secondary forest regrowth. Finally, we measured N:P resorption ratios of six canopy tree species in a Costa Rican tropical forest. We calculated species-specific resorption ratios and compared them with patterns in leaf litter and topsoil nutrient concentrations. At the global scale, N:P resorption ratios increased with latitude and decreased with mean annual temperature (MAT) and precipitation (MAP; Pswitch across latitudes: N:P resorption ratios were generally 1 in latitudes >23°. Focusing on tropical sites in our global dataset we found that, despite fewer data and a restricted latitudinal range, a significant relationship between latitude and N:P resorption ratios persisted (P<0.001). In contrast, tropical N:P resorption ratios did not vary with MAT (P=0.965) and the relationship with MAP was only marginally significant (P=0.089). Data suggest that soil type, at least in part, helps explain N:P resorption patterns across tropical latitudes: plants on more weathered soils (Oxisols and Ultisols) resorbed much more P relative to N and weathered soils were proportionally more abundant at the lowest latitudes. In our assessment of nutrient resorption along an Amazon Basin chronosequence of regenerating forests, where previous work reported a transition from apparent N limitation in younger forests to P limitation in mature forests, we found N resorption was highest in the youngest forest, whereas P resorption was greatest in the mature forest. Over the course of succession, N resorption efficiency leveled off but P resorption continued to increase with forest age. In Costa Rica, though we found species-specific patterns in resorption, data support the idea that lowland tropical forest plants on highly weathered soils resorb more P relative to N. Together, these data highlight how stoichiometric perspectives can help distill the complexity of coupled biogeochemical cycles and suggest that nutrient resorption ratios offer a complementary metric for assessing nutrient limitation in terrestrial ecosystems.

Reed, S.; Cleveland, C. C.; Davidson, E. A.; Townsend, A. R.

2013-12-01

150

Albendazole and alveolar disease: A case report  

Directory of Open Access Journals (Sweden)

Full Text Available Hydatidsis is a zoonosis transmitted by domestic and wild animals. Two distinct clinical presentations are as followes: unilocular of cystic hydatid disease and the more malignant form, called alveolar hydatid disease.This case report presents a patient who complained of chest pain and hemoptysis and his lung CT scan suggested solid tumor. He was found to have alveolar diseae which responded to albendazole medical therapy

Daneshjou Kh

2002-06-01

151

Glucocorticoids maintain human osteoclasts in the active mode of their resorption cycle  

DEFF Research Database (Denmark)

Osteoclasts are known to exert their resorptive activity through a so-called resorption cycle consisting of alternating resorption and migration episodes and resulting typically in the formation of increasing numbers of discrete round excavations on bone slices. This study shows that glucocorticoids deeply modify this resorptive behavior. First, glucocorticoids gradually induce excavations with a trenchlike morphology while reducing the time-dependent increase in excavation numbers. This indicates that glucocorticoids make osteoclasts elongate the excavations they initiated rather than migrating to a new resorption site, as in control conditions. Second, the round excavations in control conditions contain undegraded demineralized collagen as repeatedly reported earlier, whereas the excavations with a trenchlike morphology generated under glucocorticoid exposure appear devoid of leftovers of demineralized collagen. This indicates that collagenolysis proceeds generally at a lower rate than demineralization under control conditions, whereas collagenolysis rates are increased up to the level of demineralization rates in the presence of glucocorticoids. Taking these observations together leads to a model where glucocorticoid-induced increased collagenolysis allows continued contact of osteoclasts with mineral, thereby maintaining resorption uninterrupted by migration episodes and generating resorption trenches. In contrast, accumulation of demineralized collagen, as prevails in controls, acts as a negative-feedback loop, switching resorptive activity off and promoting migration to a new resorption site, thereby generating an additional resorption pit. We conclude that glucocorticoids change the osteoclastic resorption mode from intermittent to continuous and speculate that this change may contribute to the early bone fragilization of glucocorticoid-treated patients.

SØe, Kent; Delaissé, Jean-Marie

2010-01-01

152

Inflammatory root resorption in primary molars: prevalence and associated factors  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english This study aimed at determining the prevalence of inflammatory root resorption and associated factors in 1068 primary mandibular molars in 453 children 3 to 12 years of age. Age, dental history and medical history were recorded using a questionnaire administered to the children's parents/caregivers. [...] Previously trained and calibrated examiners assessed radiographic images of the primary molars by direct observation, with the aid of a viewing box. Root resorption (physiological or inflammatory), dental crown status (healthy, carious with no pulp involvement, carious with pulp involvement and evidence of restoration), and pulpotomy or pulpectomy were determined. Data analysis involved descriptive statistics, the chi-square test and a multiple logistic regression (p

Raquel Gonçalves, Vieira-Andrade; Clarissa Lopes, Drumond; Laura Pereira Azevedo, Alves; Leandro Silva, Marques; Maria Letícia, Ramos-Jorge.

153

Risk variables of external apical root resorption during orthodontic treatment  

Digital Repository Infrastructure Vision for European Research (DRIVER)

INTRODUCTION: External apical root resorption (EARR) is an adverse outcome of the orthodontic treatment. So far, no single or associated factor has been identified as responsible for EARR due to tooth movement. OBJECTIVE: This study investigated the association of risk variables (age, gender, extraction for orthodontic treatment and Angle classification) with EARR and orthodontic treatment. METHOD: The sample (n=72) was divided into two groups according to presence (n=32) or absence (n=40) of...

Maria Carolina Feio Barroso; Renan Lana Devita; Eugênio José Pereira Lages; Fernando de Oliveira Costa; Alexandre Fortes Drummond; Henrique Pretti; Elizabeth Maria Bastos Lages

2012-01-01

154

Cortical Bone Resorption Following Muscle Paralysis is Spatially Heterogeneous  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mechanical loading of the skeleton, as induced by muscle function during activity, plays a critical role in maintaining bone homeostasis. It is not understood, however, whether diminished loading (and thus diminished mechanical stimuli) directly mediates the bone resorption that is associated with disuse. Our group has recently developed a murine model in which we have observed rapid and profound bone loss in the tibia following transient paralysis of the calf muscles. As cortical bone loss i...

Ausk, Brandon J.; Huber, Philippe; Poliachik, Sandra L.; Bain, Steven D.; Srinivasan, Sundar; Gross, Ted S.

2012-01-01

155

Tropomyosin 4 regulates adhesion structures and resorptive capacity in osteoclasts.  

Science.gov (United States)

Tropomyosins (Tms) are alpha-helical dimers that bind and stabilize actin microfilaments while regulating their accessibility to other actin-associated proteins. Four genes encode expression of over forty Tms, most of which are expressed in nonmuscle cells. In recent years, it has become clear that individual Tm isoforms may regulate specific actin pools within cells. In this study, we examined how osteoclast function may be regulated by the tropomyosin isoform Tm-4, which we previously showed to be highly localized to podosomes and sealing zones of osteoclasts. RNAi-mediated knockdown of Tm-4, both in RAW264.7- and mouse marrow-derived osteoclasts, resulted in thinning of the actin ring of the sealing zone. Knockdown of Tm-4 also resulted in diminished bone resorptive capacity and altered resorption pit shape. In contrast, osteoclasts overexpressing Tm-4 demonstrated thickened podosomes on glass as well as thickened, aberrant actin structures on bone, and diminished motility and resorptive capacity. These results indicate that Tm-4 plays a role in regulating adhesion structures of osteoclasts, most likely by stabilizing the actin microfilaments present in podosomes and the sealing zone. PMID:18036591

McMichael, Brooke K; Lee, Beth S

2008-02-01

156

Vertical and horizontal ridge augmentation in anterior maxilla using autograft, xenograft and titanium mesh with simultaneous placement of endosseous implants  

Science.gov (United States)

Endosseous implants have revolutionized the field of Implants and Periodontics. Implant placement is a viable option in the treatment of partial and full edentulism. However, placement of implants in alveolar deficiencies may lead to adverse angulations, mechanical overload and esthetic dissatisfaction. When minimum dimensions for implant placement are not present in alveolar process, it is necessary to augment the size of the ridge. This can be achieved by various methods and materials. Here we present a successful case of vertical and horizontal ridge augmentation in anterior maxilla using autograft, xenograft and titanium mesh with simultaneous placement of implants, where autograft was obtained from the same site avoiding secondary surgical site. PMID:25425833

Deshpande, Sudhendra; Deshmukh, Jeevanand; Deshpande, Sumeet; Khatri, Richa; Deshpande, Shubha

2014-01-01

157

Compression-absorption (resorption) refrigerating machinery. Modeling of reactors; Machine frigorifique a compression-absorption (resorption). Modelisation des reacteurs  

Energy Technology Data Exchange (ETDEWEB)

This paper is a series of transparencies presenting a comparative study of the thermal performances of different types of refrigerating machineries: di-thermal with vapor compression, tri-thermal with moto-compressor, with ejector, with free piston, adsorption-type, resorption-type, absorption-type, compression-absorption-type. A prototype of ammonia-water compression-absorption heat pump is presented and modeled. (J.S.)

Lottin, O.; Feidt, M.; Benelmir, R. [LEMTA-UHP Nancy-1, 54 - Vandoeuvre-les-Nancy (France)

1997-12-31

158

Effects of surface microtopography on the assembly of the osteoclast resorption apparatus.  

Science.gov (United States)

Bone degradation by osteoclasts depends on the formation of a sealing zone, composed of an interlinked network of podosomes, which delimits the degradation lacuna into which osteoclasts secrete acid and proteolytic enzymes. For resorption to occur, the sealing zone must be coherent and stable for extended periods of time. Using titanium roughness gradients ranging from 1 to 4.5 µm R(a) as substrates for osteoclast adhesion, we show that microtopographic obstacles of a length scale well beyond the range of the 'footprint' of an individual podosome can slow down sealing-zone expansion. A clear inverse correlation was found between ring stability, structural integrity and sealing-zone translocation rate. Direct live-cell microscopy indicated that the expansion of the sealing zone is locally arrested by steep, three-dimensional 'ridge-like barriers', running parallel to its perimeter. It was, however, also evident that the sealing zone can bypass such obstacles, if pulled by neighbouring regions, extending through flanking, obstacle-free areas. We propose that sealing-zone dynamics, while being locally regulated by surface roughness, are globally integrated via the associated actin cytoskeleton. The effect of substrate roughness on osteoclast behaviour is significant in relation to osteoclast function under physiological and pathological conditions, and may constitute an important consideration in the design of advanced bone replacements. PMID:22090285

Geblinger, Dafna; Zink, Christian; Spencer, Nicholas D; Addadi, Lia; Geiger, Benjamin

2012-07-01

159

The influence of ovariectomy, simvastatin and sodium alendronate on alveolar bone in rats / Influência da ovariectomia, da sinvastatina e do alendronato sódico no osso alveolar em ratas  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Os bisfosfonatos são empregados atualmente para o tratamento de várias doenças caracterizadas pelo aumento da reabsorção óssea, como a osteoporose. As estatinas são amplamente utilizadas para redução de níveis elevados de colesterol e estudos recentes têm revelado sua ação anabólica no osso. O objet [...] ivo deste trabalho foi avaliar a influência da deficiência estrogênica e dos tratamentos com sinvastatina ou alendronato sódico no osso alveolar em ratas. Cinqüenta e quatro ratas sofreram ovariectomia (OVX) ou cirurgia simulada ("sham"). Um mês após, os animais passaram a receber diariamente, via oral, 25 mg/kg de sinvastatina (SIN), 2 mg/kg de alendronato (ALN) ou água (controle). Trinta e cinco dias depois do início do tratamento os animais foram sacrificados, as hemimandíbulas esquerdas removidas e radiografadas em aparelho de raios X digital. Foi calculada a densidade radiográfica em tons de cinza da área de osso alveolar sob o primeiro molar mandibular e os valores foram submetidos a ANOVA, ao nível de 5%. Ratas ovariectomizadas ganharam mais peso (média ± desvio-padrão: 20,06 ± 6,68%) que as demais (12,13 ± 5,63%). Os valores de densidade radiográfica, em tons de cinza, foram menores nos animais do grupo OVX-água (183,49 ± 6,47), significantemente diferentes daqueles observados nos grupos que receberam alendronato ("sham"-ALN: 193,85 ± 3,81; OVX-ALN: 196,06 ± 5,11) e no grupo "sham"-água (193,66 ± 4,36). Outras comparações entre grupos não revelaram diferenças estatísticas. Concluiu-se que a ovariectomia reduziu a densidade óssea alveolar e que o tratamento com alendronato sódico foi eficiente para o tratamento desta situação. Abstract in english Bisphosphonates are currently used in the treatment of many diseases involving increased bone resorption such as osteoporosis. Statins have been widely used for the treatment of hypercholesterolemia and recent studies have shown that these drugs are also capable of stimulating bone formation. The pu [...] rpose of this study was to evaluate the influence of an estrogen deficient state and the effects of simvastatin and sodium alendronate therapies on alveolar bone in female rats. Fifty-four rats were either ovariectomized (OVX) or sham operated. A month later, the animals began to receive a daily dose of simvastatin (SIN - 25 mg/kg), sodium alendronate (ALN - 2 mg/kg) or water (control) orally. Thirty-five days after the beginning of the treatment, the rats were sacrificed and their left hemimandibles were removed and radiographed using digital X-ray equipment. The alveolar radiographic density under the first molar was determined with gray-level scaling and the values were submitted to analysis of variance (a = 5%). Ovariectomized rats gained more weight (mean ± standard deviation: 20.06 ± 6.68%) than did the sham operated animals (12.13 ± 5.63%). Alveolar radiographic density values, expressed as gray levels, were lowest in the OVX-water group (183.49 ± 6.47), and differed significantly from those observed for the groups receiving alendronate (sham-ALN: 193.85 ± 3.81; OVX-ALN: 196.06 ± 5.11) and from those of the sham-water group (193.66 ± 4.36). Other comparisons between groups did not show significant differences. It was concluded that the ovariectomy reduced alveolar bone density and that alendronate was efficient for the treatment of this condition.

Ana Lia, Anbinder; Fernanda de Almeida, Prado; Marcela de Almeida, Prado; Ivan, Balducci; Rosilene Fernandes da, Rocha.

2007-09-01

160

The influence of ovariectomy, simvastatin and sodium alendronate on alveolar bone in rats / Influência da ovariectomia, da sinvastatina e do alendronato sódico no osso alveolar em ratas  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Os bisfosfonatos são empregados atualmente para o tratamento de várias doenças caracterizadas pelo aumento da reabsorção óssea, como a osteoporose. As estatinas são amplamente utilizadas para redução de níveis elevados de colesterol e estudos recentes têm revelado sua ação anabólica no osso. O objet [...] ivo deste trabalho foi avaliar a influência da deficiência estrogênica e dos tratamentos com sinvastatina ou alendronato sódico no osso alveolar em ratas. Cinqüenta e quatro ratas sofreram ovariectomia (OVX) ou cirurgia simulada ("sham"). Um mês após, os animais passaram a receber diariamente, via oral, 25 mg/kg de sinvastatina (SIN), 2 mg/kg de alendronato (ALN) ou água (controle). Trinta e cinco dias depois do início do tratamento os animais foram sacrificados, as hemimandíbulas esquerdas removidas e radiografadas em aparelho de raios X digital. Foi calculada a densidade radiográfica em tons de cinza da área de osso alveolar sob o primeiro molar mandibular e os valores foram submetidos a ANOVA, ao nível de 5%. Ratas ovariectomizadas ganharam mais peso (média ± desvio-padrão: 20,06 ± 6,68%) que as demais (12,13 ± 5,63%). Os valores de densidade radiográfica, em tons de cinza, foram menores nos animais do grupo OVX-água (183,49 ± 6,47), significantemente diferentes daqueles observados nos grupos que receberam alendronato ("sham"-ALN: 193,85 ± 3,81; OVX-ALN: 196,06 ± 5,11) e no grupo "sham"-água (193,66 ± 4,36). Outras comparações entre grupos não revelaram diferenças estatísticas. Concluiu-se que a ovariectomia reduziu a densidade óssea alveolar e que o tratamento com alendronato sódico foi eficiente para o tratamento desta situação. Abstract in english Bisphosphonates are currently used in the treatment of many diseases involving increased bone resorption such as osteoporosis. Statins have been widely used for the treatment of hypercholesterolemia and recent studies have shown that these drugs are also capable of stimulating bone formation. The pu [...] rpose of this study was to evaluate the influence of an estrogen deficient state and the effects of simvastatin and sodium alendronate therapies on alveolar bone in female rats. Fifty-four rats were either ovariectomized (OVX) or sham operated. A month later, the animals began to receive a daily dose of simvastatin (SIN - 25 mg/kg), sodium alendronate (ALN - 2 mg/kg) or water (control) orally. Thirty-five days after the beginning of the treatment, the rats were sacrificed and their left hemimandibles were removed and radiographed using digital X-ray equipment. The alveolar radiographic density under the first molar was determined with gray-level scaling and the values were submitted to analysis of variance (a = 5%). Ovariectomized rats gained more weight (mean ± standard deviation: 20.06 ± 6.68%) than did the sham operated animals (12.13 ± 5.63%). Alveolar radiographic density values, expressed as gray levels, were lowest in the OVX-water group (183.49 ± 6.47), and differed significantly from those observed for the groups receiving alendronate (sham-ALN: 193.85 ± 3.81; OVX-ALN: 196.06 ± 5.11) and from those of the sham-water group (193.66 ± 4.36). Other comparisons between groups did not show significant differences. It was concluded that the ovariectomy reduced alveolar bone density and that alendronate was efficient for the treatment of this condition.

Ana Lia, Anbinder; Fernanda de Almeida, Prado; Marcela de Almeida, Prado; Ivan, Balducci; Rosilene Fernandes da, Rocha.

 
 
 
 
161

The influence of ovariectomy, simvastatin and sodium alendronate on alveolar bone in rats Influência da ovariectomia, da sinvastatina e do alendronato sódico no osso alveolar em ratas  

Directory of Open Access Journals (Sweden)

Full Text Available Bisphosphonates are currently used in the treatment of many diseases involving increased bone resorption such as osteoporosis. Statins have been widely used for the treatment of hypercholesterolemia and recent studies have shown that these drugs are also capable of stimulating bone formation. The purpose of this study was to evaluate the influence of an estrogen deficient state and the effects of simvastatin and sodium alendronate therapies on alveolar bone in female rats. Fifty-four rats were either ovariectomized (OVX or sham operated. A month later, the animals began to receive a daily dose of simvastatin (SIN - 25 mg/kg, sodium alendronate (ALN - 2 mg/kg or water (control orally. Thirty-five days after the beginning of the treatment, the rats were sacrificed and their left hemimandibles were removed and radiographed using digital X-ray equipment. The alveolar radiographic density under the first molar was determined with gray-level scaling and the values were submitted to analysis of variance (a = 5%. Ovariectomized rats gained more weight (mean ± standard deviation: 20.06 ± 6.68% than did the sham operated animals (12.13 ± 5.63%. Alveolar radiographic density values, expressed as gray levels, were lowest in the OVX-water group (183.49 ± 6.47, and differed significantly from those observed for the groups receiving alendronate (sham-ALN: 193.85 ± 3.81; OVX-ALN: 196.06 ± 5.11 and from those of the sham-water group (193.66 ± 4.36. Other comparisons between groups did not show significant differences. It was concluded that the ovariectomy reduced alveolar bone density and that alendronate was efficient for the treatment of this condition.Os bisfosfonatos são empregados atualmente para o tratamento de várias doenças caracterizadas pelo aumento da reabsorção óssea, como a osteoporose. As estatinas são amplamente utilizadas para redução de níveis elevados de colesterol e estudos recentes têm revelado sua ação anabólica no osso. O objetivo deste trabalho foi avaliar a influência da deficiência estrogênica e dos tratamentos com sinvastatina ou alendronato sódico no osso alveolar em ratas. Cinqüenta e quatro ratas sofreram ovariectomia (OVX ou cirurgia simulada ("sham". Um mês após, os animais passaram a receber diariamente, via oral, 25 mg/kg de sinvastatina (SIN, 2 mg/kg de alendronato (ALN ou água (controle. Trinta e cinco dias depois do início do tratamento os animais foram sacrificados, as hemimandíbulas esquerdas removidas e radiografadas em aparelho de raios X digital. Foi calculada a densidade radiográfica em tons de cinza da área de osso alveolar sob o primeiro molar mandibular e os valores foram submetidos a ANOVA, ao nível de 5%. Ratas ovariectomizadas ganharam mais peso (média ± desvio-padrão: 20,06 ± 6,68% que as demais (12,13 ± 5,63%. Os valores de densidade radiográfica, em tons de cinza, foram menores nos animais do grupo OVX-água (183,49 ± 6,47, significantemente diferentes daqueles observados nos grupos que receberam alendronato ("sham"-ALN: 193,85 ± 3,81; OVX-ALN: 196,06 ± 5,11 e no grupo "sham"-água (193,66 ± 4,36. Outras comparações entre grupos não revelaram diferenças estatísticas. Concluiu-se que a ovariectomia reduziu a densidade óssea alveolar e que o tratamento com alendronato sódico foi eficiente para o tratamento desta situação.

Ana Lia Anbinder

2007-09-01

162

A radiologic study of the teeth resorption in the area of a ameloblastoma  

Energy Technology Data Exchange (ETDEWEB)

An ameloblastoma produces more extensive resorption of the teeth on which it encroaches than do most of the other lesions. In this study, intraoral and extraoral radiographs of 78 cases of ameloblastoma were observed and the root resorption associated with ameloblastoma was classified into four types of resorption. With these, the following conclusions were obtained. 1. The root resorption was observed in 72 cases of ameloblastoma. (92.3%) 2. In the aspect of resorptive changes of 424 roots observed, 342 roots showed smooth resorption. (80.6%) 3. The 424 roots associated with ameloblastoma revealed the following radiographic features. a) Root apex resorption in contact with the lesion appeared in 189 roots. (44.5%) b) The resorption of roots projected into the lesion appeared in 147 roots. (34.5%) c) Slight resorption of root surface in contact with the lesion was observed in 56 roots. (13.2%) d) Loss of lamina dura and periodontal space without root resorption were observed in 32 roots. (7.7%)

Yee, Choon Aei; Park, Tae Won [Yonsei University College of Medicine, Seoul (Korea, Republic of)

1980-11-15

163

A radiologic study of the teeth resorption in the area of a ameloblastoma  

International Nuclear Information System (INIS)

An ameloblastoma produces more extensive resorption of the teeth on which it encroaches than do most of the other lesions. In this study, intraoral and extraoral radiographs of 78 cases of ameloblastoma were observed and the root resorption associated with ameloblastoma was classified into four types of resorption. With these, the following conclusions were obtained. 1. The root resorption was observed in 72 cases of ameloblastoma. (92.3%) 2. In the aspect of resorptive changes of 424 roots observed, 342 roots showed smooth resorption. (80.6%) 3. The 424 roots associated with ameloblastoma revealed the following radiographic features. a) Root apex resorption in contact with the lesion appeared in 189 roots. (44.5%) b) The resorption of roots projected into the lesion appeared in 147 roots. (34.5%) c) Slight resorption of root surface in contact with the lesion was observed in 56 roots. (13.2%) d) Loss of lamina dura and periodontal space without root resorption were observed in 32 roots. (7.7%)

164

A scanning electron microscopic study of the patterns of external root resorption under different conditions  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVE: The aim of this study was to examine if there are qualitative differences in the appearance of external root resorption patterns of primary teeth undergoing physiologic resorption and permanent teeth undergoing pathological root resorption in different conditions. MATERIAL AND METHODS: A total of 40 teeth undergoing external root resorption in different conditions were divided into 4 groups and prepared for examination under scanning electron microscopy at magnifications ranging from 20x to 1000x. Group I: 10 primary molars exfoliated due to physiologic root resorption; Group II: 10 permanent teeth with periapical granulomas showing signs of resorption; Group III:10 permanent teeth therapeutically extracted during the course of orthodontic therapy with evidence of resorption, and Group IV: 10 permanent teeth associated with odontogenic tumors that showed evidence of resorption. RESULTS: In Group I, the primary teeth undergoing resorption showed smooth extensive and predominantly regular areas reflecting the slow ongoing physiologic process. In Group II, the teeth with periapical granulomas showed the resorption was localized to apex with a funnel shaped appearance in most cases. Teeth in Group III, which had been subjected to a short period of light orthodontic force, showed the presence of numerous resorption craters with adjoining areas of cemental repair in some cases. Teeth associated with odontogenic tumors in Group IV showed many variations in the patterns of resorption with extensive loss of root length and a sharp cut appearance of the root in most cases. CONCLUSION: Differences were observed in the patterns of external root resorption among the studied groups of primary and permanent teeth under physiologic and pathological conditions.

Ravindran Sreeja

2009-10-01

165

A scanning electron microscopic study of the patterns of external root resorption under different conditions  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVE: The aim of this study was to examine if there are qualitative differences in the appearance of external root resorption patterns of primary teeth undergoing physiologic resorption and permanent teeth undergoing pathological root resorption in different conditions. MATERIAL AND METHODS: A [...] total of 40 teeth undergoing external root resorption in different conditions were divided into 4 groups and prepared for examination under scanning electron microscopy at magnifications ranging from 20x to 1000x. Group I: 10 primary molars exfoliated due to physiologic root resorption; Group II: 10 permanent teeth with periapical granulomas showing signs of resorption; Group III:10 permanent teeth therapeutically extracted during the course of orthodontic therapy with evidence of resorption, and Group IV: 10 permanent teeth associated with odontogenic tumors that showed evidence of resorption. RESULTS: In Group I, the primary teeth undergoing resorption showed smooth extensive and predominantly regular areas reflecting the slow ongoing physiologic process. In Group II, the teeth with periapical granulomas showed the resorption was localized to apex with a funnel shaped appearance in most cases. Teeth in Group III, which had been subjected to a short period of light orthodontic force, showed the presence of numerous resorption craters with adjoining areas of cemental repair in some cases. Teeth associated with odontogenic tumors in Group IV showed many variations in the patterns of resorption with extensive loss of root length and a sharp cut appearance of the root in most cases. CONCLUSION: Differences were observed in the patterns of external root resorption among the studied groups of primary and permanent teeth under physiologic and pathological conditions.

Ravindran, Sreeja; Chaudhary, Minal; Tumsare, Madhuri; Patil, Swati; Wadhwan, Vijay.

2009-10-01

166

Morphometric analysis of maxillary alveolar regions for immediate implantation  

Science.gov (United States)

PURPOSE The purpose of this study was to provide an actual guideline in determining the shape, diameter, and position of the implant in immediate implantation by the measurement of the thickness of facial and palatal plate, the thickness of cortical bone on the facial and palatal plate, the diameter of the root, and the distance between the roots in the cadavers. MATERIALS AND METHODS The horizontal sections of 20 maxillae were measured and analyzed to obtain the average values. Resin blocks were produced and cut serially at 1 mm intervals from the cervical line to the root apex. Images of each section were obtained and the following measurements were performed: The thickness of the facial and palatal residual bone at each root surface, the thickness of the facial and palatal cortical bone at the interdental region, the diameter of all roots of each section on the faciopalatal and mesiodistal diameter, and the interroot distance. Three specimens with measurements close to the average values were chosen and 3-dimensional images were reconstructed. RESULTS The thickness of the facial and palatal cortical bone at the interdental region in the maxilla, the buccal cortical bone was thicker in the posterior region compared to the anterior region. The interroot distance of the alveolar bone thickness between the roots increased from anterior to posterior region and from coronal to apical in the maxilla. CONCLUSION In this study, the limited results of the morphometric analysis of the alveolar ridge using the sections of maxilla in the cadavers may offer the useful information when planning and selecting optimal implant for immediate implantation in the maxilla. PMID:24353891

Park, Man-Soo; Park, Young-Bum; Choi, Hyunmin; Moon, Hong-Seok; Chung, Moon-Kyu; Cha, In-Ho

2013-01-01

167

Em busca de uma causa à parte da Ortodontia: hereditariedade e reabsorção apical em pacientes tratados ortodonticamente. Uma análise crítica do trabalho de Harris, Kineret e Tolley / In search of a cause apart of Orthodontics: heredity and apical resorption in patients treated Orthodontically. A critical analysis of Harris, Kineret, Tolley’s work  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Exclusivamente a partir da equivalência radiográfica do padrão e intensidade de reabsorção dentária em tratamento ortodôntico de 103 irmãos, Harris, Kineret e Tolley12 tentaram impingir um caráter hereditário a este fenômeno sem considerar a morfologia dentária e maxilar, nem tampouco outros fatores [...] envolvidos na etiopatogenia das reabsorções. No trabalho fica claro que entre os objetivos principais dos autores estava atribuir à hereditariedade a ocorrência de reabsorções dentárias durante o tratamento ortodôntico para aliviar em parte as responsabilidades profissionais perante os pacientes e a sociedade. Mas nos parece mais lógico que o profissional devesse habilitar-se para fazer a previsibilidade das reabsorções dentárias com base em seus planejamentos, considerando a morfologia radicular, o tipo de ápice dentário, a proporção coroa-raiz e a morfologia da crista óssea alveolar, bem como evitando escolher, sempre que possível, os procedimentos que mais usualmente estão associados à reabsorção radicular. Se o paciente apresentar-se com morfologias desfavoráveis e ainda assim necessitar de procedimentos associados a um maior risco de reabsorção em seu tratamento, que o mesmo seja informado e conscientizado que as reabsorções dentárias apicais serão um custo biológico para a recuperação de sua estética e função. Considerando: 1) a grande limitação proporcionada pelo diagnóstico de reabsorções apicais em radiografias panorâmicas e telerradiografias em norma lateral (cefalométricas); 2) a ausência de análise da morfologia dentária e da crista óssea alveolar; e 3) principalmente a falta de um grupo controle para comparar se os resultados seriam equivalentes, ou não, em uma população semelhante, sem qualquer parentesco, mas com as mesmas características dentomaxilares; pode-se afirmar que as conclusões do trabalho estão severamente comprometidas em sua credibilidade científica. Tanto a abordagem empregada na discussão quanto as conclusões obtidas pelos autores, sobre correlação entre genótipo, fenótipo e reabsorção dentária, parecem despropositadas, pois não houve estudos envolvendo células, nem tampouco uma metodologia de identificação de genes ou aplicação de qualquer técnica cujos resultados permitissem inferências desta natureza. Abstract in english Harris, Kineret, Tolley12 tried to implicate heritability to root resorption exclusively though radiographic equivalence between the pattern of resorption intensity after orthodontic treatment in 103 siblings. Neither dental nor facial morphology or any other etiopathogenic factor of root resorption [...] was considered, whatsoever.It is clear in this study that the authors´ main goal was to attribute root resorption during orthodontic treatment to heritability in order to lighten the professional’s share of responsibility before patients and society. It seems more logic that the professional should try to predict root resorption when considering on treatment plan the root and alveolar crest morphology, the type of apex, crown-root proportion, and avoiding procedures known to cause more resorption. If a patient presents unfavorable morphology and still needs procedures associated with a higher risk of resorption, than he or she must be warned and informed that apical root resorption will be a biological cost to regain estetics and function. Considering on this paper: (1) the limitations to evaluate apical resorption in panoramic and cephalometric radiographs; (2) the absence of dental and alveolar crest morphology analysis; and (3) the lack of a control group in order to compare if the results would be equivalent in a similar population with no family ties but with same maxilofacial conditions; one can affirm that the scientific credibility of the conclusions are severely damaged. The conclusions drawn by the authors about genotype and phenotype concerning root resorption seem unfounded, since there was no ce

Alberto, Consolaro; Maria Fernanda, Martins-Ortiz.

168

Alveolar rhabdomyosarcoma in children with histomorphological review  

Directory of Open Access Journals (Sweden)

Full Text Available Rhabdomyosarcomas (RMS are aggressive malignant neoplasm of mesenchymal origin, related to skeletal muscle lineage. These are the most common soft tissue tumors in children. The diagnosis is made by microscopic analysis and ancillary techniques like immunohistochemistry, electron microscopy, cytogenetics and molecular biology. We encountered a case of a 03 years old child who presented with a tender, reddish, soft swelling over cheek for three weeks. The FNAC was reported as a small round cell tumor, Probably Primitive Neuroectodermal Tumor (PNET. The biopsy of tumor revealed a small round cell tumor with an alveolar pattern. Tumor giant cells were absent and mitotic figures were infrequent. Hence, differentials of alveolar rhabdomyosarcoma and PNET were rendered. Immunohistochemistry (IHC demonstrated desmin positivity. Thus, a final diagnosis of alveolar rhabdomyosarcoma was offered. [Int J Res Med Sci 2014; 2(2.000: 775-778

S. K. Nema

2014-04-01

169

Whole lung lavage for pulmonary alveolar proteinosis  

Directory of Open Access Journals (Sweden)

Full Text Available A 26-year-old male presented with complaints of dry cough of six months and progressive breathlessness of three months duration. He was coughing out milky white sputum for two months and had lost 12 kg weight in two months. He had an evening rise in temperature of one month duration. Clinically, the patient was in respiratory distress and the respiratory system examination revealed bilateral velcro crackles. High resolution computed tomography chest showed bilateral diffuse reticulonodular opacities and "Crazy Paving" pattern suggestive of alveolar proteinosis. Broncho alveolar lavage showed eosinophilic granular material, which was periodic acid-Schiff positive. Open lung biopsy was done to confirm the diagnosis and the histopathologic examination revealed eosinophilic secretions with granular appearance suggestive of pulmonary alveolar proteinosis. Subsequently, patient underwent bilateral sequential whole lung lavage under general anesthesia. Patient showed marked clinical and radiological improvement after sequential whole lung lavage.

Jayaraman S

2010-01-01

170

Effect of icariin on cell proliferation and the expression of bone resorption/formation-related markers in human periodontal ligament cells.  

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Periodontitis is a common destructive inflammatory disease that leads to changes in the tooth-supporting tissues. Human periodontal ligament cells are essential in periodontal tissue regeneration. The traditional Chinese medicine icariin promoted bone formation, stimulated the osteogenic differentiation of preosteoblastic cells and inhibited osteoclast differentiation and bone resorption. Thus, in the present study, the effect of icariin on cell proliferation and the expression of osteoprotegerin (OPG), receptor activator of nuclear factor-?B ligand (RANKL), core binding factor ?1 (Cbfa1) and osteocalcin (OC) was investigated in human periodontal ligament cells, by an MTT assay, qPCR and western blot analysis. The results demonstrated that icariin promoted cell proliferation in a dose- and time-dependent manner, upregulated OPG, Cbfa1 and OC expression, and downregulated RANKL production and the RANKL/OPG expression ratio. This suggested the potential value of icariin in treating alveolar bone resorption and promoting periodontal tissue regeneration, due to its ability to stimulate the proliferation and osteogenic differentiation of human periodontal ligament cells and inhibit osteoclast differentiation. PMID:24065204

Pei, Zhenhua; Zhang, Fengqiu; Niu, Zhongying; Shi, Shenggen

2013-11-01

171

ALVEOLAR BREATH SAMPLING AND ANALYSIS IN HUMAN EXPOSURE ASSESSMENT STUDIES  

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Alveolar breath sampling and analysis can be extremely useful in exposure assessment studies involving volatile organic compounds (VOCs). Over recent years scientists from the EPA's National Exposure Research Laboratory have developed and refined an alveolar breath collection ...

172

Bone sialoprotein deficiency impairs osteoclastogenesis and mineral resorption in vitro.  

Science.gov (United States)

Bone sialoprotein (BSP) and osteopontin (OPN) belong to the small integrin-binding ligand N-linked glycoprotein (SIBLING) family, whose members interact with bone cells and bone mineral. Previously, we showed that BSP knockout (BSP(-/-) ) mice have a higher bone mass than wild type (BSP(+/+) ) littermates, with very low bone-formation activity and reduced osteoclast surfaces and numbers. Here we report that approximately twofold fewer tartrate-resistant acid phosphatase (TRACP)-positive cells and approximately fourfold fewer osteoclasts form in BSP(-/-) compared with BSP(+/+) spleen cell cultures. BSP(-/-) preosteoclast cultures display impaired proliferation and enhanced apoptosis. Addition of RGD-containing proteins restores osteoclast number in BSP(-/-) cultures to BSP(+/+) levels. The expression of osteoclast-associated genes is markedly altered in BSP(-/-) osteoclasts, with reduced expression of cell adhesion and migration genes (?V integrin chain and OPN) and increased expression of resorptive enzymes (TRACP and cathepsin K). The migration of preosteoclasts and mature osteoclasts is impaired in the absence of BSP, but resorption pit assays on dentine slices show no significant difference in pit numbers between BSP(+/+) and BSP(-/-) osteoclasts. However, resorption of mineral-coated slides by BSP(-/-) osteoclasts is markedly impaired but is fully restored by coating the mineral substrate with hrBSP and partly restored by hrOPN coating. In conclusion, lack of BSP affects both osteoclast formation and activity, which is in accordance with in vivo findings. Our results also suggest at least some functional redundancy between BSP and OPN that remains to be clarified. PMID:20812227

Boudiffa, Maya; Wade-Gueye, Ndéye Marième; Guignandon, Alain; Vanden-Bossche, Arnaud; Sabido, Odile; Aubin, Jane E; Jurdic, Pierre; Vico, Laurence; Lafage-Proust, Marie Hélène; Malaval, Luc

2010-12-01

173

Management of External Invasive Cervical Resorption Tooth with Mineral Trioxide Aggregate: A Case Report  

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Invasive cervical resorption is entirely uncommon entities and the etiology is poorly understood. A 19 year old patient presented with fractured upper left central incisor and sinus tract opening on the distobuccal aspect in cervical region. Radiographic examination shows irregular radiolucency over the coronal one-third and it extended externally towards the external invasive resorption. After sectional obturation, the defect was accessed surgically. The resorption area was chemomechanically...

Anuja Ikhar; Nikita Thakur; Aditya Patel; Rohan Bhede; Pranav Patil; Surbhi Gupta

2013-01-01

174

Conservative management of progressive external inflammatory root resorption after traumatic tooth intrusion.  

Science.gov (United States)

Intrusive luxation is one of the most severe types of dental trauma. The risk of development of inflammatory or replacement root resorption is high if not timely managed. Endodontic intervention is required soon after the occurrence of trauma, in an attempt to prevent or delay inflammatory root resorption. This case report emphasized timely referral for endodontic management of intruded tooth to prevent inflammatory root resorption. PMID:23833464

Ghafoor, Robia

2013-05-01

175

Nonsurgical Endodontic Retreatment of Advanced Inflammatory External Root Resorption Using Mineral Trioxide Aggregate Obturation  

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Inflammatory external root resorption is one of the major complications after traumatic dental injury. In this case report, we describe treatment of a maxillary central incisor affected by severe, perforating external root resorption. An 18-year-old patient presented with a previously traumatized, root-filled maxillary central incisor associated with pain and sinus tract. Radiographic examination revealed periradicular lesion involving pathologic resorption of the apical region of the root an...

Sangeeta Talwar; Gaurav Garg; Shipra Arora; Shivani Utneja

2012-01-01

176

Root resorption after dental traumas: classification and clinical, radiographic and histologic aspects  

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Introduction: One of the most common sequelae observed after dental trauma is root resorption. Objective: The aim of this study was to classify and discuss the external root resorption after a dental trauma, based on a literature review. Literature review: A bibliographic search was performed in the following databases: Medline, PubMed, and Lilacs, from 1997 to 2010. The following descriptors were used: Root resorption, Dental trauma and Classification. From a total of 152 articles found, 25...

Bruno Oliveira de Aguiar Santos; Diego Santiago de Mendonça; Denise Lins de Sousa; José Jeová Siebra Moreira Neto; Rebeca Bastos Rocha de Araújo

2011-01-01

177

Conservative management of progressive external inflammatory root resorption after traumatic tooth intrusion  

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Intrusive luxation is one of the most severe types of dental trauma. The risk of development of inflammatory or replacement root resorption is high if not timely managed. Endodontic intervention is required soon after the occurrence of trauma, in an attempt to prevent or delay inflammatory root resorption. This case report emphasized timely referral for endodontic management of intruded tooth to prevent inflammatory root resorption.

Ghafoor, Robia

2013-01-01

178

Descrição fonética eletropalatográfica de fones alveolares / Phonetic description of alveolar phones using electropalatography  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Realizar a descrição articulatória do Português Brasileiro, examinando-se o contato da língua com o palato na produção de fones consonantais. MÉTODOS: Foi utilizada a eletropalatografia (EPG) de consoantes alveolares do Português Brasileiro de um sujeito com fala típica, considerando-se o [...] índice alveolar, pós-alveolar, palatal e velar e a porcentagem de contatos ativados no ponto de máxima constrição, assim como a inspeção visual dos palatogramas. RESULTADOS: Observou-se, conforme o esperado, que todos os fones avaliados têm, no ponto de máxima constrição, maior contato na região alveolar. Os fones /t/, /d/ e /n/ foram os que apresentaram maior contato alveolar, com obstrução total da corrente aérea; os fones fricativos /s/ e /z/ caracterizaram-se pela ausência de contato no eixo longitudinal central; o fone lateral /l/ não apresentou contato no eixo longitudinal lateral e o tapa, /?/, apresentou poucos contatos da língua com o palato e foi produzido com o menor tempo de duração. CONCLUSÃO: Por meio da eletropalatografia, pode-se fazer uma descrição detalhada da forma e da extensão do contato língua-palato nos diferentes fones alveolares do Português. Abstract in english PURPOSE: To describe the articulation of the Brazilian Portuguese, by examining the tongue-palate contact in the production of consonantal phones. METHODS: The electropalatography (EPG) of the alveolar consonants of the Brazilian Portuguese produced by an individual with typical speech was used, con [...] sidering the alveolar, post-alveolar, palatal, and velar rates, as well as the percentage of activated contacts at the point of maximum constriction, and the visual inspection of palatograms. RESULTS: As expected, it was observed that all the examined phones have more contact in the alveolar region at the point of maximum constriction. The phones /t/, /d/ and /n/ showed more alveolar contact, with total obstruction of the air stream; the fricative phones /s/ and /z/ were characterized by the absence of contact at the central longitudinal axis; the lateral phone /l/ did not present contact at the lateral longitudinal axis, and the tap /?/ showed not only few tongue-palate contacts but it was also produced in the shortest duration time. CONCLUSION: The electopalatography allowed a detailed description of the extension of the tongue-palate contact in the different alveolar phones of the Brazilian Portuguese and how they occur.

Marisa de Sousa Viana, Jesus; Cesar, Reis.

179

[Corticoids and alveolar surfactant. Experimental study].  

Science.gov (United States)

The effect of cortisone on the production of surfactant was studied by measuring the tensioactive property of the alveolar fluid, evaluated with Pattle's method. The stability ratio (R.S.) values obtained in 12 guinea-pigs following cortisone administration were all within normal limits. In rabbits treated with prednisolone during a number of fast days, S.R. values were lower than normal in 9 cases out of 10. The results of this study would seem to exclude any influence of the administration of cortisone on the activity of the alveolar surfactant. PMID:1173939

Cardellino, G; Dalmasso, F; Garbagni, R; Sappé, D

1975-08-01

180

Stresses in implant-supported overdentures with bone resorption: a 3-D finite element analysis / Tensões em sobredentaduras com reabsorção óssea: análise por elementos finitos tridimensional  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: Avaliar, através da análise por elementos finitos com modelo tridimensional, o efeito da reabsorção óssea na distribuição de tensões em prótese tipo overdenture, em situações de perda óssea ao redor dos implantes e reabsorção do rebordo posterior. METODOLOGIA: Foram construídos modelos tri [...] dimensionais de uma mandíbula e de intermediários protéticos, prótese total, placa resiliente e implante. Os modelos geométricos dos implantes e intermediários protéticos foram montados na região dos caninos, constituindo o modelo 1. Para a construção dos modelos experimentais, o contorno do modelo geométrico da mandíbula foi alterado para simular a perda óssea nos implantes (modelo 2) e a reabsorção do rebordo posterior associada à perda óssea marginal nos implantes (modelo 3). Para gerar a malha de elementos finitos os materiais foram considerados homogêneos, isotrópicos e linearmente elásticos. Uma carga de 100 N foi aplicada indiretamente, sobre uma simulação de bolo alimentar, na região de primeiro molar inferior direito em cada um dos três modelos. Foram analisadas as distribuições de tensão de von Mises em pontos pré-determinados. RESULTADOS: A reabsorção óssea do rebordo posterior associada à perda óssea do osso periimplantar promoveu maior concentração de tensões nos implantes, nos componentes protéticos e no tecido ósseo marginal. Houve maior concentração de tensões no osso periimplantar e nos implantes no mesmo lado de aplicação da carga. CONCLUSÃO: Os resultados sugerem que a perda óssea periimplantar aumenta a concentração de tensões nos implantes, pilares e osso marginal independentemente da reabsorção óssea na crista distal. Abstract in english PURPOSE: This 3D-finite elements method study evaluated the effect of bone resorption on the stress distribution in overdentures with bone loss surrounding implants and resorption of the distal ridge. METHODS: Tridimensional models were built from the images of a computerized tomography of a mandibl [...] e and 3D laser digitalization of implants, abutments, mucosa, and complete denture. The geometric models of implants and abutments were mounted at the canine region to build reference model 1 - absence of bone resorption. To build the test models the mandible geometric solid was modified to simulate 2-mm vertical bone loss surrounding the implants (model 2) and resorption of the distal ridge (model 3). Finite elements models were generated, and a 100 N static load was applied at the first molar region of each model to compare the von Mises stress distributions in selected points. RESULTS: Von Mises stresses increased on the bone surrounding implants and on the prosthetic components in the model with 2-mm vertical bone loss. The combination of 2-mm vertical bone loss and resorption of the distal ridge did not increase the stresses compared with the model with only bone loss surrounding implants. The highest stress concentration at marginal bone and implants occurred on the same side of the vertical load application for all models. CONCLUSION: The results suggest that the bone loss surrounding implants increases stress concentration in dental implants, abutments, and marginal bone independently from the bone resorption of the distal ridge.

Luiz Oscar Honorato, Mariano; Evandro Afonso, Sartori; Josué Ricardo, Broilo; Rosemary Sadami, Shinkai; Leandro, Corso; Rogério José, Marczak.

 
 
 
 
181

Surgical management of invasive cervical resorption using resin-modified glass ionomer cement.  

Science.gov (United States)

Invasive cervical resorption is an external resorption that begins below the epithelial attachment. It is caused primarily by dental trauma, orthodontic treatment, or dental bleaching. This case report involved an invasive Class III cervical resorption resulting from trauma to the superior right central incisor. Root canal treatment was followed by surgical intervention. The resorptive defect was debrided, and part of the tooth was restored with resin-modified glass ionomer cement. Postoperative follow-up revealed complete healing and healthy gingival attachment. PMID:24192742

Tavares, Warley Luciano Fonseca; Lopes, Renata Carvalho Portes; Oliveira, Ricardo Reis; Souza, Rodrigo Goncalves de; Henriques, Luiz Carlos Feitosa; Ribeiro-Sobrinho, Antonio Paulino

2013-01-01

182

Soft tissue expansion before vertical ridge augmentation: Inflatable silicone balloons or self-filling osmotic tissue expanders?  

Science.gov (United States)

Recent advances in periodontal plastic surgical procedures allow the clinician to reconstruct deficient alveolar ridges in more predictable ways than previously possible. Placement of implant/s in resorbed ridges poses numerous challenges to the clinician for successful esthetic and functional rehabilitation. The reconstruction frequently utilizes one or combination of periodontal plastic surgical procedures in conjunction with autogenous bone grafting, allogenic bone block grafting, ridge split techniques, distraction osteogenesis, or guided bone regeneration (GBR) for most predictable outcomes. Current surgical modalities used in reconstruction of alveolar ridge (horizontal and/or vertical component) often involve the need of flap transfer. Moreover, there is compromise in tissue integrity and color match owing to different surgical site and the tissue utilized is insufficient in quantity leading to post surgical graft exposition and/or loss of grafted bone. Soft tissue expansion (STE) by implantation of inflatable silicone balloon or self filling osmotic tissue expanders before reconstructive surgery can overcome these disadvantages and certainly holds a promise for effective method for generation of soft tissue thereby achieving predictable augmentation of deficient alveolar ridges for the implant success. This article focuses and compares these distinct tissue expanders for their clinical efficacy of achieving excess tissue that predominantly seems to be prerequisite for ridge augmentation which can be reasonably followed by successful placement of endosseous fixtures. PMID:25210255

Dhadse, Prasad Vijayrao; Yeltiwar, Ramareddy Krishnarao; Bhongade, Manohar Laxmanrao; Pendor, Sunil Dattuji

2014-07-01

183

Biodegradable Effect of PLGA Membrane in Alveolar Bone Regeneration on Beagle Dog.  

Science.gov (United States)

Guided bone regeneration (GBR) is a principle adopted from guided tissue regeneration (GTR). Wherein, GBR is used for the healing of peri-implant bony dehiscences, for the immediate placement of implants into extraction sockets and for the augmentation of atrophic alveolar ridges. This procedure is done by the placement of a resorbable or non-resorbable membrane that will exclude undesirable types of tissue growth between the extraction socket and the soft tissue to allow only bone cells to regenerate in the surgically treated lesion. Here, we investigated the biodegradable effect of polylactic-co-glycolic acid (PLGA) membrane in the alveolar bone on Beagle dogs. Results show that both collagen and PLGA membrane had been fully resorbed, biodegraded, at four weeks post-operative reentry into the alveolar bone. Histological results under light microscopy revealed formation of new bone trabeculae in the extraction sites on both collagen and PLGA membrane. In conclusion, PLGA membrane could be a potential biomaterials for use on GBR and GTR. Nevertheless, further studies will be necessary to elucidate the efficiency and cost effectiveness of PLGA as GBR membrane in clinical. PMID:24833431

Hua, Nan; Ti, Vivian Lao; Xu, Yuanzhi

2014-11-01

184

Control of bone resorption in mice by Schnurri-3.  

Science.gov (United States)

Mice lacking the large zinc finger protein Schnurri-3 (Shn3) display increased bone mass, in part, attributable to augmented osteoblastic bone formation. Here, we show that in addition to regulating bone formation, Shn3 indirectly controls bone resorption by osteoclasts in vivo. Although Shn3 plays no cell-intrinsic role in osteoclasts, Shn3-deficient animals show decreased serum markers of bone turnover. Mesenchymal cells lacking Shn3 are defective in promoting osteoclastogenesis in response to selective stimuli, likely attributable to reduced expression of the key osteoclastogenic factor receptor activator of nuclear factor-?B ligand. The bone phenotype of Shn3-deficient mice becomes more pronounced with age, and mice lacking Shn3 are completely resistant to disuse osteopenia, a process that requires functional osteoclasts. Finally, selective deletion of Shn3 in the mesenchymal lineage recapitulates the high bone mass phenotype of global Shn3 KO mice, including reduced osteoclastic bone catabolism in vivo, indicating that Shn3 expression in mesenchymal cells directly controls osteoblastic bone formation and indirectly regulates osteoclastic bone resorption. PMID:22573816

Wein, Marc N; Jones, Dallas C; Shim, Jae-Hyuck; Aliprantis, Antonios O; Sulyanto, Rosalyn; Lazarevic, Vanja; Poliachik, Sandra L; Gross, Ted S; Glimcher, Laurie H

2012-05-22

185

[Comparative studies of amoxicillin resorption and distribution in poultry].  

Science.gov (United States)

Comparative experiments were carried out to test the resorption and retention of amoxicillin-trihydrate, ampicillin-trihydrate and amopen-powder Pharmachim drug formula (containing 5 per cent amoxicillin-trihydrate) following a single oral application to chickens and wild ducks. Higher was the resorption of amoxicillin as a trihydrate in comparison to ampicillin as trihydrate (it provides concentrations twice as high in the blood of chickens). The ducks were found to utilize amoxicillin as trihydrate in a similar manner, however, they excrete it more rapidly. The distribution of the preparation was determined in the viscera of chickens treated with amoxicillin via the feed at the rate of 20.0 /kg feed in the course of six days. It was found that amoxicillin was retained in therapeutic concentrations in the liver, kidneys, lungs, and muscles, and in lower concentrations in the spleen and heart. It was established that the brain also contained negligible amounts of the preparation. The tissue concentrations did not surpass the serum ones. PMID:6659342

Lashev, L; Semerdzhiev, V

1983-01-01

186

Microlitiasis alveolar pulmonar: caso clínico / Pulmonary alveolar microlithiasis: Report of one case  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish [...] Abstract in english Pulmonary alveolar microlithiasis is an extremely rare disease characterized by intra-alveolar accumulation of calcified spherical particles (called microliths), due to a mutation of the gene encoding a membrane transport protein of the alveolar surface. Most patients are asymptomatic at diagnosis. [...] The course of the disease is slowly progressive, with development of pulmonary fibrosis and respiratory failure. The "sandstorm" pattern is the characteristic finding of this disease. We report a 39-year-old female presenting with progressive dyspnea. A chest X ray showed ground-glass opacities and a high resolution CT scan showed numerous calcified lung micronodules. A surgical lung biopsy confirmed the diagnosis of pulmonary alveolar microlithiasis.

Cristina, Fernández F; Mauricio, Salinas F; José Andrés, de Grazia K; Juan Carlos, Díaz P.

187

Microlitiasis alveolar pulmonar: caso clínico / Pulmonary alveolar microlithiasis: Report of one case  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish [...] Abstract in english Pulmonary alveolar microlithiasis is an extremely rare disease characterized by intra-alveolar accumulation of calcified spherical particles (called microliths), due to a mutation of the gene encoding a membrane transport protein of the alveolar surface. Most patients are asymptomatic at diagnosis. [...] The course of the disease is slowly progressive, with development of pulmonary fibrosis and respiratory failure. The "sandstorm" pattern is the characteristic finding of this disease. We report a 39-year-old female presenting with progressive dyspnea. A chest X ray showed ground-glass opacities and a high resolution CT scan showed numerous calcified lung micronodules. A surgical lung biopsy confirmed the diagnosis of pulmonary alveolar microlithiasis.

Cristina, Fernández F; Mauricio, Salinas F; José Andrés, de Grazia K; Juan Carlos, Díaz P.

2014-05-01

188

Alveolar Macrophage Cathelicidin Deficiency in Severe Sarcoidosis  

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Dysfunctional immune responses characterize sarcoidosis but the status of cathelicidin, a potent immunoregulatory and anti-microbial molecule has not been established in clinical disease activity. Alveolar macrophage cathelicidin expression was determined in biopsy-proven sarcoidosis patients classified clinically as “severe” (requiring systemic treatment) or “non-severe” (never requiring treatment). Sarcoidosis and healthy control bronchoalveolar lavage (BAL) cells were analyzed for ...

Barna, Barbara P.; Culver, Daniel A.; Kanchwala, Ali; Singh, Ravinder J.; Huizar, Isham; Abraham, Susamma; Malur, Anagha; Marshall, Irene; Kavuru, Mani S.; Thomassen, Mary Jane

2012-01-01

189

Ridges on basalt flows  

Science.gov (United States)

Pressure ridges are surface features on basaltic lava flows and, as with other surface features, they may be related to the emplacement of a flow and the rheological properties of the lava. Since many ridges are of sufficient size to be detected on high resolution orbital images, an understanding of pressure ridges could provide a means for interpreting volcanic flows on other terrestrial planets. Some proposed formation mechanisms are reviewed and three different types of pressure ridges are identified on the basis of morphology. Type 1 ridges are the most common and are associated with multiple flow unit pahoehoe in which the ridges are embayed by secondary toe fed lava. They tend to be restricted to wider sections or margins of the flow and to be oriented longitudinal to flow direction; however, oblique or transverse orientation is not uncommon. Bulbous squeeze ups are common within cracks and may reflect relative timing of crack formation. The interior structure of type 1 ridges consists of an upper slab section which generally contains columnar joints and a lower massive section with an irregular surface. This basic distinction may mark the thickness of the surface crust when ridge formation was initiated. Type 2 ridges occur in association with type 1 and are very similar with the exception of the secondary squeeze out material. Instead of only filling cracks, the secondary material on these ridges originated from underneath a thin crust and flowed as toes or channels from the top and sides of the ridge. Type 3 ridges have much steeper sides (almost vertical at the top) than the other types. Medial cracks are very wide and the crack walls are convex upward. No squeeze ups are present. The main difference between type 3 and the others may be reflection of viscosity.

Theilig, E.

1984-04-01

190

Ridges on basalt flows  

Science.gov (United States)

Pressure ridges are surface features on basaltic lava flows and, as with other surface features, they may be related to the emplacement of a flow and the rheological properties of the lava. Since many ridges are of sufficient size to be detected on high resolution orbital images, an understanding of pressure ridges could provide a means for interpreting volcanic flows on other terrestrial planets. Some proposed formation mechanisms are reviewed and three different types of pressure ridges are identified on the basis of morphology. Type 1 ridges are the most common and are associated with multiple flow unit pahoehoe in which the ridges are embayed by secondary toe fed lava. They tend to be restricted to wider sections or margins of the flow and to be oriented longitudinal to flow direction; however, oblique or transverse orientation is not uncommon. Bulbous squeeze ups are common within cracks and may reflect relative timing of crack formation. The interior structure of type 1 ridges consists of an upper slab section which generally contains columnar joints and a lower massive section with an irregular surface. This basic distinction may mark the thickness of the surface crust when ridge formation was initiated. Type 2 ridges occur in association with type 1 and are very similar with the exception of the secondary squeeze out material. Instead of only filling cracks, the secondary material on these ridges originated from underneath a thin crust and flowed as toes or channels from the top and sides of the ridge. Type 3 ridges have much steeper sides (almost vertical at the top) than the other types. Medial cracks are very wide and the crack walls are convex upward. No squeeze ups are present. The main difference between type 3 and the others may be reflection of viscosity.

Theilig, E.

1984-01-01

191

Orthodontic treatment and root resorption of teeth: Critical analysis of mechanical factors.  

Directory of Open Access Journals (Sweden)

Full Text Available AIM: The aim of this review is the presentation and critical analysis of the mechanical factors associated with orthodontic treatment and implicated in the formation of root resorption.METHOD: Original articles and reviews pertaining to this topic were searched at the data base PubMed until May 2009.FINDINGS: Root resorption shows considerable variations. Individuals may present minimal or significant resorption, more than 3 mm while a percentage of 5% may present more than 5 mm. The magnitude of forces applied by the orthodontist seems to be among the mechanical factors that may affect the formation of resorptions, while intrusion and jiggling seem to be the most harmful among the teeth movement types. Teeth resorptions also seem to be associated with the type and duration of the applied forces, the range of tooth movement, as well as with genetic and biological factors, rendering this way the dissociation and the degree of participation of these factors in the appearance of resorptions particularly difficult.CONCLUSIONS: Root resorptions of teeth are an unanticipated phenomenon of multifactorial etiology. Up until now, it seems that there is not enough evidence that could lead to specific strategies efficient to minimize or prevent the phenomenon of root resorption.

Ioulia Ioannidou-Marathiotou

2010-01-01

192

Bone formation and resorption are both increased in experimental autoimmune arthritis  

DEFF Research Database (Denmark)

Arthritic bone loss in the joints of patients with rheumatoid arthritis is the result of a combination of osteoclastic bone resorption and osteoblastic bone formation. This process is not completely understood, and especially the importance of local inflammation needs further investigation. We evaluated how bone formation and bone resorption are altered in experimental autoimmune arthritis.

Keller, Kresten Krarup; Thomsen, Jesper Skovhus

2012-01-01

193

The Bone Resorption Inhibitors Odanacatib and Alendronate Affect Post-Osteoclastic Events Differently in Ovariectomized Rabbits  

DEFF Research Database (Denmark)

Odanacatib (ODN) is a bone resorption inhibitor which differs from standard antiresorptives by its ability to reduce bone resorption without decreasing bone formation. What is the reason for this difference? In contrast with other antiresorptives, such as alendronate (ALN), ODN targets only the very last step of the resorption process. We hypothesize that ODN may therefore modify the remodeling events immediately following osteoclastic resorption. These events belong to the reversal phase and include recruitment of osteoblasts, which is critical for connecting bone resorption to formation. We performed a histomorphometric study of trabecular remodeling in vertebrae of estrogen-deficient rabbits treated or not with ODN or ALN, a model where ODN, but not ALN, was previously shown to preserve bone formation. In line with our hypothesis, we found that ODN treatment compared to ALN results in a shorter reversal phase, faster initiation of osteoid deposition on the eroded surfaces, and higher osteoblast recruitment. The latter is reflected by higher densities of mature bone forming osteoblasts and an increased subpopulation of cuboidal osteoblasts. Furthermore, we found an increase in the interface between osteoclasts and surrounding osteoblast-lineage cells. This increase is expected to favor the osteoclast-osteoblast interactions required for bone formation. Regarding bone resorption itself, we show that ODN, but not ALN, treatment results in shallower resorption lacunae, a geometry favoring bone stiffness. We conclude that, compared to standard antiresorptives, ODN shows distinctive effects on resorption geometry and on reversal phase activities which positively affect osteoblast recruitment and may therefore favor bone formation.

Jensen, Pia Rosgaard; Andersen, Thomas Levin

2014-01-01

194

Systemic alendronate prevents resorption of necrotic bone during revascularization. A bone chamber study in rats  

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Full Text Available Abstract Background Avascular necrosis of bone (osteonecrosis can cause structural failure and subsequent deformation, leading to joint dysfunction and pain. Structural failure is the result of resorption of necrotic bone during revascularization, before new bone has formed or consolidated enough for loadbearing. Bone resorption can be reduced by bisphosphonates. If resorption of the necrotic bone could be reduced during the revascularization phase until sufficient new bone has formed, it would appear that structural failure could be avoided. Methods To test whether resorption of necrotic bone can be prevented, structural grafts were subjected to new bone ingrowth during systemic bisphosphonate treatment in a rat model. Results In rats treated with alendronate the necrotic bone was not resorbed, whereas it was almost entirely resorbed in the controls. Conclusion Systemic alendronate treatment prevents resorption of necrotic bone during revascularization. In patients with osteonecrosis, bisphosphonates may therefore prevent collapse of the necrotic bone.

Aspenberg Per

2002-08-01

195

Internal and external root resorption management: a report of two cases.  

Science.gov (United States)

The response of the dentoalveolar apparatus to infection is characterized by inflammation which may result in tooth resorption. Depending upon the type of resorption and etiology, different treatment regimens have been proposed. The following two cases demonstrate internal and external inflammatory root resorption arrest by conventional nonsurgical endodontic therapy combined with calcium hydroxide-iodoform dressing, mineral trioxide aggregate (MTA) and flowable gutta-percha system.The patient has been regularly recalled every 6 months and radiographically the apical lesion showed signs of healing and arrest of root resorption after 1 year and 6 months. How to cite this article: Hegde N, Hegde MN. Internal and External Root Resorption Management: A Report of Two Cases. Int J Clin Pediatr Dent 2013;6(1):44-47. PMID:25206188

Hegde, Nanditha; Hegde, Mithra N

2013-01-01

196

Internal and External Root Resorption Management: A Report of Two Cases  

Science.gov (United States)

ABSTRACT The response of the dentoalveolar apparatus to infection is characterized by inflammation which may result in tooth resorption. Depending upon the type of resorption and etiology, different treatment regimens have been proposed. The following two cases demonstrate internal and external inflammatory root resorption arrest by conventional nonsurgical endodontic therapy combined with calcium hydroxide-iodoform dressing, mineral trioxide aggregate (MTA) and flowable gutta-percha system.The patient has been regularly recalled every 6 months and radiographically the apical lesion showed signs of healing and arrest of root resorption after 1 year and 6 months. How to cite this article: Hegde N, Hegde MN. Internal and External Root Resorption Management: A Report of Two Cases. Int J Clin Pediatr Dent 2013;6(1):44-47.

Hegde, Mithra N

2013-01-01

197

Non-Surgical Repair of Internal Resorption with MTA: A Case Report  

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Full Text Available Internal resorption is rare in permanent teeth. Treatment is usually performed through warm gutta-percha technique. If the resorptive process perforates the root, treatment may be more difficult and is usually performed via surgical approach. Non-surgical repair of a perforating internal root resorption with MTA was conducted in this case. Before repairing the resorption, a master gutta-percha point was placed in the canal to maintain negotiability of the original canal path. Then, MTA was prepared and applied with a small carrier in the resorption area and compacted. Thereafter gutta-percha was retrieved and the access cavity was closed with a temporary filling material. In the second visit, the root canal was obturated with gutta-percha and AH26 sealer using lateral compaction technique and subsequently, the crown was restored. The symptoms and signs ceased and the result was satisfactory at the 18 month follow-up visit.

Zahed Mohammadi

2012-10-01

198

Técnica de Separación de Reborde Alveolar en Región Posterior de Mandíbula con Implante Inmediato / Splint Crest Technique for Alveolar Bone in Posterior Region of Mandible with Immediate Implant  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish La implantología actual ha evolucionado rápidamente diseñando nuevas técnicas para tratar situaciones clínicas criticas; la reabsorción ósea presenta un constante desafío para la instalación de implantes dentales. Se presenta un caso clínico donde se utilizo la técnica de separación alveolar en el s [...] ector posterior de mandíbula en conjunto con la instalación de implantes dentales; la cirugía se desarrollo con anestesia local de forma exitosa. Con un seguimiento de 10 meses se presenta de forma optima demostrando la eficiencia de la técnica. Son discutidos aspectos relevantes de la cirugía así como también los elementos que podrían ayudar a optimizar los resultados postquirúrgicos. Abstract in english Nowadays, dental implantology presents an evolution with new techniques for treatment of critical situation; bone resorption is a challenge for dental implant installation.This paper presents a case with the splint crest technique in the posterior area of mandible with installation of dental implant [...] ; the surgery was done with local anesthesia with success of procedure. A 10 month follow-up show good results presenting the efficiency of this technique.We discussed relevant aspects of the technique and other situations to improve surgical options and results.

Leandro, Pozzer; Luca, Cavalieri-Pereira; Sergio, Olate; Jose, Albergaria Barbosa; Luciana, Asprino; Marcio, de Moraes.

199

Risk variables of external apical root resorption during orthodontic treatment  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english INTRODUCTION: External apical root resorption (EARR) is an adverse outcome of the orthodontic treatment. So far, no single or associated factor has been identified as responsible for EARR due to tooth movement. OBJECTIVE: This study investigated the association of risk variables (age, gender, extrac [...] tion for orthodontic treatment and Angle classification) with EARR and orthodontic treatment. METHOD: The sample (n=72) was divided into two groups according to presence (n=32) or absence (n=40) of EARR in maxillary central and lateral incisors after orthodontic treatment. RESULTS: There were no statistically significant differences in EARR according to age, gender, extraction or type of malocclusion (p>0.05). CONCLUSION: The risk variables examined were not associated with EARR in the study population.

Maria Carolina Feio, Barroso; Renan Lana, Devita; Eugênio José Pereira, Lages; Fernando de Oliveira, Costa; Alexandre Fortes, Drummond; Henrique, Pretti; Elizabeth Maria Bastos, Lages.

200

Risk variables of external apical root resorption during orthodontic treatment  

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Full Text Available INTRODUCTION: External apical root resorption (EARR is an adverse outcome of the orthodontic treatment. So far, no single or associated factor has been identified as responsible for EARR due to tooth movement. OBJECTIVE: This study investigated the association of risk variables (age, gender, extraction for orthodontic treatment and Angle classification with EARR and orthodontic treatment. METHOD: The sample (n=72 was divided into two groups according to presence (n=32 or absence (n=40 of EARR in maxillary central and lateral incisors after orthodontic treatment. RESULTS: There were no statistically significant differences in EARR according to age, gender, extraction or type of malocclusion (p>0.05. CONCLUSION: The risk variables examined were not associated with EARR in the study population.

Maria Carolina Feio Barroso

2012-04-01

 
 
 
 
201

Effects of zinc oxide-eugenol and calcium hydroxide/ iodoform on delaying root resorption in primary molars without successors.  

Science.gov (United States)

The purpose of this study was to compare the effects of zinc oxide-eugenol (ZOE) and calcium hydroxide/iodoform paste (Vitapex), as root canal filling materials in pulpectomy, on delaying the root resorption of primary molars without permanent successors. Animal models without permanent successors were surgically established in beagle dogs. Root resorption was observed via periapical radiographs. The onset of root resorption of primary mandibular molars without successors occurred later (p<0.05) than physiologic resorption. ZOE pulpectomy clearly delayed the root resorption of primary molars without permanent successors (p<0.05), whereas resorption of primary molars with Vitapex pulpectomy started at almost the same time as physiologic resorption. Compared with Vitapex, ZOE was a more effective root canal filling material in delaying the root resorption of primary molars. PMID:25017021

Lin, Bichen; Zhao, Yuming; Yang, Jie; Wang, Wenjun; Ge, Li-hong

2014-01-01

202

A resorption refrigerator driven by low grade thermal energy  

Energy Technology Data Exchange (ETDEWEB)

Highlights: {yields} A resorption refrigerator employing MnCl{sub 2}-NH{sub 3} and NH{sub 4}Cl-NH{sub 3} was designed and investigated. {yields} The experiments were operated under different ambient temperatures from 20 to 35 {sup o}C. {yields} The refrigerator provided simultaneously two cooling levels: at 0-6 {sup o}C and at -16 {approx} -14.5 {sup o}C. {yields} With 3 h operation the total cooling capacity was 475 kJ per kg of NH{sub 4}Cl salt. {yields} The effective cooling production was 25-42% of the total cooling capacity. -- Abstract: A small refrigerator based on resorption technique, employed MnCl{sub 2} and NH{sub 4}Cl as sorbent salts and ammonia as refrigerant, was presented for simultaneously cooling at 0-6 {sup o}C and freezing at -16 to -14.5 {sup o}C in this work. The cooling capacity of this device was investigated by measuring the mass amount of the ice generated during a certain period of 3 h operation, and the experiments were conducted at different ambient temperature ranging from 20 {sup o}C to 35 {sup o}C. The total cooling capacity was calculated 475 kJ per kg of NH{sub 4}Cl salt, and the mean specific cooling power (SCP) was 43 W per kg of NH{sub 4}Cl salt, the effective cooling production responsible for making ice accounted for 25-42% of the total cooling capacity depending on the different operating conditions studied in this work.

Bao, H.S. [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Shanghai 200240 (China); Wang, R.Z., E-mail: rzwang@sjtu.edu.c [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Shanghai 200240 (China); Wang, L.W. [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Shanghai 200240 (China)

2011-06-15

203

Alveolar capillary dysplasia with anorectal anomaly.  

Science.gov (United States)

Alveolar capillary dysplasia (ACD) is an uncommon cause of irreversible persistent pulmonary hypertension in full-term newborn. In ACD there is a failure of formation of air - blood barrier in addition to misalignment of pulmonary veins. The etiology of the disease is still not understood. We present a case report of a full-term newborn with ACD associated with anorectal anomaly. PMID:22080682

Uhrikova, Zuzana; Matasova, Katarina; Jurko, Alexander; Zibolen, Mirko

2011-10-01

204

Congenital alveolar synechiae with cleft palate.  

Science.gov (United States)

Congential maxillomandibular fusion or jaw adhesions is a rare entity. It is often associated with other congenital anomalies like cleft palate and is characterized by restricted mouth opening. This unusual presentation of congenital alveolar synechiae is highlighted in a 15 days old baby boy. Under inhalational anaesthesia his fibrocartilagenous adhesions were excised and endotracheal tube was then placed. Good recovery without any residual scars or adhesions and a 25 mm mouth opening was achieved. PMID:25252496

Salahuddin, Omer; Yousaf, Kanwal; Rashid, Mamoon; Yousaf, Shumaila; Qazi, Uzair Ahmed; Ishtiaq-ur-Rehman

2014-06-01

205

In situ methods for assessing alveolar mechanics.  

Science.gov (United States)

Lung mechanics are an important determinant of physiological and pathophysiological lung function. Recent light microscopy studies of the intact lung have furthered the understanding of lung mechanics but used methodologies that may have introduced artifacts. To address this concern, we employed a short working distance water immersion objective to capture confocal images of a fluorescently labeled alveolar field on the costal surface of the isolated, perfused rat lung. Surface tension held a saline drop between the objective tip and the lung surface, such that the lung surface was unconstrained. For comparison, we also imaged with O-ring and coverslip; with O-ring, coverslip, and vacuum pressure; and without perfusion. Under each condition, we ventilated the lung and imaged the same region at the endpoints of ventilation. We found use of a coverslip caused a minimal enlargement of the alveolar field; additional use of vacuum pressure caused no further dimensional change; and absence of perfusion did not affect alveolar field dimension. Inflation-induced expansion was unaltered by methodology. In response to inflation, percent expansion was the same as recorded by all four alternative methods. PMID:22074721

Wu, You; Perlman, Carrie E

2012-02-01

206

Management of maxillary alveolar process fractures  

Directory of Open Access Journals (Sweden)

Full Text Available Incidence of maxillofacial traumas is reported steadily increasing, maxillary fractures being extremely severe. Maxillary alveolar process (AP and front teeth are traumatized more frequently than any other parts of the maxilla. Deprivation of teeth and AP post-traumatic flaw as well as loss of alveolar height not only create a cosmetic defect but also complicate subsequent prosthetics of the patients. The work was initiated to assess efficacy of “CollapAn L” in comparison with a combination of “Osteon”, an osteoplastic material, and “Colla Guide” resorbable membrane in prevention of AP post-traumatic flaws and deformities. 60 patients aged from 16 to 47 with the comminuted fractures of maxillary AP emergently hospitalized were examined and treated. The findings showed that Combination of “Osteon” and “Colla Guide” resorbable membrane is the one to increase efficacy of the treatment, facilitating preservation of and alveolar crest height and shape. In addition, preservation of bone tissue mineralization helps avoid risk of the bone wound inflammatory morbidity.

Shukhrat Boymuradov

2011-04-01

207

Root resorption after dental traumas: classification and clinical, radiographic and histologic aspects  

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Full Text Available Introduction: One of the most common sequelae observed after dental trauma is root resorption. Objective: The aim of this study was to classify and discuss the external root resorption after a dental trauma, based on a literature review. Literature review: A bibliographic search was performed in the following databases: Medline, PubMed, and Lilacs, from 1997 to 2010. The following descriptors were used: Root resorption, Dental trauma and Classification. From a total of 152 articles found, 25 were selected: 24 in English and 1 in Spanish. Classic articles were also used in our study. External root resorption after dental traumas can be divided into superficial, inflammatory and replacement. It can also be verified in primary dentition as physiological and atypical resorptions. Conclusion: Each type of resorption presents clinical features as well as radiographic and histological aspects. Therefore, the dentist should know these characteristics to perform an early diagnosis and appropriate treatment, minimizing the sequelae related to this problem. Moreover, in primary dentition, the differential diagnosis between physiological and pathological resorption is important to avoid over-treatment.

Bruno Oliveira de Aguiar Santos

2011-10-01

208

Bone resorption in incompletely impacted mandibular third molars and acute pericoronitis  

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Full Text Available Minoru Yamaoka, Yusuke Ono, Masahiro Takahashi, Ryosuke Doto, Kouichi Yasuda, Takashi Uematsu, Kiyofumi FurusawaMatsumoto Dental University, School of Dentistry, Shiojiri, Nagano, JapanAbstract: Acute pericoronitis (AP arises frequently in incompletely impacted mandibular third molars, but it remains unknown whether bone resorption in aging is associated with acute inflammation of the third molar. We conducted an experiment to compare the ratio of bone resorption to root length in the distal surface of the second molar (A, the proximal surface (B, and distal surface (C in mesio-angular, incompletely impacted third molars in 27 young and 58 older adults with AP and 77 young and 79 older adults without a history of AP. Bone resorption in A, B, and C in older adults with AP demonstrated a significantly higher ratio when compared to those without AP, whereas there was no difference between those with and without AP in young adults except for B in women. However, there were no differences between bone resorption in B with AP in young and older women, and between bone resorption in C with AP in young and older adults. These indicate that AP and bone resorption are associated with incompletely impacted mandibular third molars in older adults.Keywords: bone resorption, pericoronitis, mandible, acute inflammation, elderly

Minoru Yamaoka

2009-04-01

209

Secretory and accessory cell functions of the alveolar macrophage.  

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We have attempted to address the requirements necessary for alveolar macrophage accessory cell function. We have also examined the in vitro and in vivo factors that must be taken into account when interpreting results from experimental studies. Differences in phenotypic expression by rat alveolar pleural and peritoneal macrophages are noted, as well as the differing expression of major histocompatibility complex (MHC) class II molecules. Furthermore, alveolar macrophages, harvested from rat l...

Miller, K.; Hudspith, B. N.; Meredith, C.

1992-01-01

210

PERIAPICAL RESORPTIVE PROCESSES IN CHRONIC APICAL PERIODONTITIS: AN OVERVIEW AND DISCUSSION OF THE LITERATURE.  

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Full Text Available Introduction: Root resorption is a biological phenomenon, characterized by processes of cement and/or dentine depletion, resulting from the physiological or pathological activity of resorptive cells. Purpose: The aim of this article is to review of the literature on the peculiarities of the periapical resorptive processes. Conclusion: The absence of a physiological narrowing is challenging to the achievement of satisfactory early and late therapeutic results. It makes probable either the overpressing of necrotic, infected material when preparing the endodontic space or the overpressing of the sealer when sealing the root canal.

Angela Gusiyska

2014-10-01

211

The mode of progression of subperiosteal resorption in the hyperparathyroidism of chronic renal future  

International Nuclear Information System (INIS)

Subperiosteal resorption in finger phalanges is usually thought to be the result of osteoclastic bone resorption on the periosteal surface of bone, progressive centripetally with creation of the serrated appearances and ''lace-like'' patterns in periosteal cortical bone. Our longitudinal microradioscopic observations in patients with secondary hyperparathyroidism of chronic renal failure have revealed evidence of another pathogenetic mechanism: by the enlargement of intracortical juxtaperiosteal resorption spaces, the remaining thin layer of bone is broken down from inside the bone, i.e., a centrifugal rather then centripetal process. (orig.)

212

Evolución en el tratamiento de la atrofia alveolar  

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Full Text Available Con el objetivo de describir la evolución del tratamiento de la atrofia alveolar se realiza una revisión bibliográfica actualizada de 25 referencias, se destacan las vestibuloplastias, injertos óseos, biomateriales, implantes endóseos, regeneración ósea guiada y la distracción ósea, que corrigen o compensan la atrofia alveolar con sus indicaciones, ventajas y desventajas.An updated literature review of 25 references was made to describe the development in the treatment of dental alveolar atrophy. Some procedures that correct or compensate alveolar atrophies such as vestibuloplasty, bone grafting, biomaterials, endo-bone implants, guided bone regeneration and bone distraction. Their indications, advantages and disadvantages are set forth.

Oscar García-Roco Pérez

2002-08-01

213

Prosthodontic management of flat mandibular ridge by mini implant supported over denture.  

Science.gov (United States)

Loosening of lower denture has always been a common complaint of denture wearer, particularly in case of severe bone resorption. Various treatment modalities including preprosthetic surgery or ridge augmentation therapy to improve the ridge height and conventional implant treatments are available. But many patients are not willing to undergo through such extensive surgical procedure or conventional twin stage implant therapy owing to the chronic old age ailment and cost factor. So mini implant (SENDAX MDI) supported over denture is a boon for them who want a quick and minimally invasive solution, with a much lower cost. In this article we shall discuss the case report of a 60-year-old female patient with atropic mandibular ridge rehabilitated with MDI, (mini dental implant), Sendax mini implant. PMID:25177653

Garhnayak, Mirna; Garhnayak, Lokanath; Dev, Shruti; Kar, Aswini Kumar; Mohapatra, Abhijita

2014-07-01

214

Effect of allergen sensitization on external root resorption.  

Science.gov (United States)

In orthodontic tooth movement (OTM), we should be concerned about external root resorption (ERR) as an undesirable iatrogenic problem, but its mechanisms are not fully understood. Since our previous epidemiologic studies found that patients with allergic diseases showed higher rates of ERR during orthodontic treatment, we explored the possible effect of allergic sensitization on ERR. In ovalbumin (OVA)-sensitized Brown-Norway rats, the amounts of ERR and OTM were greater than those in animals subjected to orthodontic force alone. The expression levels of RANKL and pro-inflammatory cytokines were increased in the periodontal tissues of sensitized rats with OTM, compared with control rats. Furthermore, leukotriene B4 (LTB4), a potent lipid mediator of allergic inflammation, and enzymes of the 5-lipoxygenase pathway, the biosynthetic pathway of leukotrienes, were also up-regulated. We found that low doses of aspirin suppressed ERR in allergen-sensitized rats, as well as the expressions of RANKL, pro-inflammatory cytokines, and LTB4. The present findings indicate that allergen sensitization has adverse effects on ERR under OTM, and that aspirin is a potential therapeutic agent for combating ERR. PMID:23648742

Murata, N; Ioi, H; Ouchi, M; Takao, T; Oida, H; Aijima, R; Yamaza, T; Kido, M A

2013-07-01

215

Management of mucosal fenestration with external root resorption by multidisciplinary approach.  

Science.gov (United States)

Mucosal fenestration is a clinical condition in which the overlying gingiva is denuded and the root is exposed to the oral cavity. Invasive cervical resorption is an entirely uncommon entity and its aetiology is poorly understood. This case presents an invasive cervical resorption of maxillary right central incisor with fenestration at the cervical third of the tooth. The resorption area was chemomechanically debrided. It was then restored with Mineral Trioxide Aggregate over which pink glass ionomer cement (GC Fuji VII) was placed. Lateral pedicle flap was used to cover the fenestration. The resorptive defect was restored using tooth coloured restorative resin after removal of the pink glass ionomer cement. Orthodontic treatment was continued for correction of malocclusion. PMID:25301425

Bharti, Ramesh; Chandra, Anil; Tikku, Aseem Prakash; Prasad, Veerendra; Shakya, Vijay Kumar; Singhal, Rameshweri

2014-01-01

216

Nonsurgical endodontic retreatment of advanced inflammatory external root resorption using mineral trioxide aggregate obturation.  

Science.gov (United States)

Inflammatory external root resorption is one of the major complications after traumatic dental injury. In this case report, we describe treatment of a maxillary central incisor affected by severe, perforating external root resorption. An 18-year-old patient presented with a previously traumatized, root-filled maxillary central incisor associated with pain and sinus tract. Radiographic examination revealed periradicular lesion involving pathologic resorption of the apical region of the root and lateral root surface both mesially and distally. After removal of the root canal filling, the tooth was disinfected with intracanal triple antibiotic paste for 2 weeks. The antibiotic dressing was then removed, and the entire root canal was filled with mineral trioxide aggregate. The endodontic access cavity was restored with composite resin. After 18 months, significant osseous healing of the periradicular region and lateral periodontium had occurred with arrest of external root resorption, and no clinical symptoms were apparent. PMID:23304567

Utneja, Shivani; Garg, Gaurav; Arora, Shipra; Talwar, Sangeeta

2012-01-01

217

Response of Bone Resorption Markers to Aristolochia longa Intake by Algerian Breast Cancer Postmenopausal Women.  

Science.gov (United States)

Aristolochia longa is widely used in traditional medicine in Algeria to treat breast cancer. The aim of the present study was to investigate the response of bone resorption markers to A. longa intake by Algerian breast cancer postmenopausal women. According to the A. longa intake, breast cancer patients were grouped into A. longa group (Al) (n = 54) and non-A. longa group (non-Al) (n = 24). 32 women constituted the control group. Bone resorption markers (from urine) pyridinoline (PYD) and deoxypyridinoline (DPD) were determined by HPLC. Serum and urinary creatinine, uric acid, and urea were measured. 1?g of A. longa intake resulted in significant rise of renal serum markers and a pronounced increase of bone resorption markers. The intake of A. longa roots is detrimental for kidney function and resulted in high bone resorption, maybe due to the reduction in renal function caused by the aristolochic acids contained in the roots. PMID:24876833

Benarba, Bachir; Meddah, Boumedienne; Tir Touil, Aicha

2014-01-01

218

Beneficial role of periosteum in distraction osteogenesis of mandible. Its preservation prevents the external bone resorption  

International Nuclear Information System (INIS)

observed in two out of three dogs at 6-month post-consolidation. These findings suggest that preservation of periosteum prevents the external bone resorption during the vertical DO of mandible. (author)

219

Influence of diphenylhydantoin on lysosomal enzyme release during bone resorption in vitro  

International Nuclear Information System (INIS)

The effect of diphenylhydantoin (DPH) on the release of lysosomal enzymes during resorption of cultured mouse calvarial bone was studied. The enzyme activities of ?-glucuronidase and ?-galactosidase in the culture medium was taken as indicators for lysosomal enzyme release. In concentrations 50 ?g/ml or higher, DPH inhibited the release of ?-glucuronidase and ?-galactosidase in parallel with bone resorption as indicated by reduced release of 4Ca, Ca2, Psub(i) and hydroxyproline. The release of the cytosolic enzyme lactate dehydrogenase was not influenced by concentrations of DPH up to 50 ?g/ml but higher concentrations caused an increased release indicating cell injury. When bone resorption was stimulated by prostaglandin E2, DPH(50 ?g/ml) also reduced the mobilization of bone mineral and the release of ?- glucuronidase without influencing the release of lactate dehydrogenase. It is suggested that DPH by interfering with cellular release processes reduces the resorption on bone. (author)

220

Nutrient resorption in shrubs growing by design, and by default in Chihuahuan Desert arroyos.  

Science.gov (United States)

In the northern stretches of the Chihuahuan Desert, the margins of ephemeral stream channels called arroyos support a unique vegetation dominated by a guild of winter-deciduous shrubs. To explore the dynamics of nutrient conservation in this assemblage of arroyo shrubs, we measured nitrogen (N) and phosphorus (P) resorption efficiency and proficiency in six species of shrubs growing in arroyos in southern New Mexico. Collectively, these six species were no more efficient or proficient at resorbing N and P from senescing leaves than shrubs growing in other environments. Resorption efficiency averaged 53% and 50% for N and P, respectively, and resorption proficiency averaged 0.80% and 0.06% for N and P, respectively. However, resorption varied significantly between species specifically restricted in their distribution to riparian habitats (obligate riparian species), and those that were not. The two obligate riparian species combined (Brickellia laciniata, Chilopsis linearis) were significantly more efficient and proficient at resorbing N than the non-obligate riparian species combined (Fallugia paradoxa, Flourensia cernua, Prosopis glandulosa, Rhus microphylla). Additionally, both Brickellia and Chilopsis were individually significantly more proficient at resorbing N than any of the other four species. The dichotomy in resorption between obligate riparian species and those that were not may have been the result of the interplay between hydrology, geomorphology, and biology. Because arroyos move in space as the movement of water erodes banks and changes channel location, some plants are found along arroyos only because the arroyos have moved to them. These plants (plants growing by default) may be less well adapted to arroyo margins than obligate riparian species (plants growing by design). Significant differences in resorption between obligate and non-obligate riparian species suggested that evolutionary history and habitat specificity may be added to the list of factors known to influence resorption. Selected life history traits of the six species did not appear to be related to any measure of resorption, but leaf surface area, specific leaf mass, and nutrient concentrations in green leaves were all correlated with resorption efficiency or proficiency in one or more species. The only species capable of symbiotic N fixation, Prosopis glandulosa, retained at least 2.3 times more N in its senesced leaves than any other species. Patterns of resorption in arroyo shrubs strongly indicated that efficiency and proficiency are fundamentally different, complementary measures of resorption. PMID:24549904

Killingbeck, K; Whitford, W

2001-08-01

 
 
 
 
221

The bone resorption inhibitors odanacatib and alendronate affect post-osteoclastic events differently in ovariectomized rabbits.  

Science.gov (United States)

Odanacatib (ODN) is a bone resorption inhibitor which differs from standard antiresorptives by its ability to reduce bone resorption without decreasing bone formation. What is the reason for this difference? In contrast with other antiresorptives, such as alendronate (ALN), ODN targets only the very last step of the resorption process. We hypothesize that ODN may therefore modify the remodeling events immediately following osteoclastic resorption. These events belong to the reversal phase and include recruitment of osteoblasts, which is critical for connecting bone resorption to formation. We performed a histomorphometric study of trabecular remodeling in vertebrae of estrogen-deficient rabbits treated or not with ODN or ALN, a model where ODN, but not ALN, was previously shown to preserve bone formation. In line with our hypothesis, we found that ODN treatment compared to ALN results in a shorter reversal phase, faster initiation of osteoid deposition on the eroded surfaces, and higher osteoblast recruitment. The latter is reflected by higher densities of mature bone forming osteoblasts and an increased subpopulation of cuboidal osteoblasts. Furthermore, we found an increase in the interface between osteoclasts and surrounding osteoblast-lineage cells. This increase is expected to favor the osteoclast-osteoblast interactions required for bone formation. Regarding bone resorption itself, we show that ODN, but not ALN, treatment results in shallower resorption lacunae, a geometry favoring bone stiffness. We conclude that, compared to standard antiresorptives, ODN shows distinctive effects on resorption geometry and on reversal phase activities which positively affect osteoblast recruitment and may therefore favor bone formation. PMID:24085265

Jensen, Pia Rosgaard; Andersen, Thomas Levin; Pennypacker, Brenda L; Duong, Le T; Delaissé, Jean-Marie

2014-02-01

222

[Spontaneous resorption of thoracic calcified disc herniation: Report of two cases and review of the literature].  

Science.gov (United States)

We report on two cases of spontaneous resorption of a calcified thoracic hernia. This phenomenom is widely recognised in lumbar and cervical hernia, but is exceptional at the thoracic level. The potential mechanisms underlying this resorption are discussed trough a review of the literature. We think this could be another argument for a "wait and watch" period before a surgical decision in the patients who have few symptoms. PMID:22743329

Eap, C; Bennis, S; Blauwblomme, T; Compaore, P; Chamsedine, A; Mireau, E; Aldea, S; Gaillard, S

2012-12-01

223

Osteoclasts on bone and dentin in vitro: mechanism of trail formation and comparison of resorption behavior.  

Science.gov (United States)

The main function of osteoclasts in vivo is the resorption of bone matrix, leaving behind typical resorption traces consisting of pits and trails. The mechanism of pit formation is well described, but less is known about trail formation. Pit-forming osteoclasts possess round actin rings. In this study we show that trail-forming osteoclasts have crescent-shaped actin rings and provide a model that describes the detailed mechanism. To generate a trail, the actin ring of the resorption organelle attaches with one side outside the existing trail margin. The other side of the ring attaches to the wall inside the trail, thus sealing that narrow part to be resorbed next (3–21 lm). This 3D configuration allows vertical resorption layer-by-layer from the surface to a depth in combination with horizontal cell movement. Thus, trails are not just traces of a horizontal translation of osteoclasts during resorption. Additionally, we compared osteoclastic resorption on bone and dentin since the latter is the most frequently used in vitro model and data are extrapolated to bone. Histomorphometric analyses revealed a material-dependent effect reflected by an 11-fold higher resorption area and a sevenfold higher number of pits per square centimeter on dentin compared to bone. An important material-independent aspect was reflected by comparable mean pit area (?m²) and podosome patterns. Hence, dentin promotes the generation of resorbing osteoclasts, but once resorption has started, it proceeds independently of material properties. Thus, dentin is a suitable model substrate for data acquisition as long as osteoclast generation is not part of the analyses. PMID:24022329

Rumpler, M; Würger, T; Roschger, P; Zwettler, E; Sturmlechner, I; Altmann, P; Fratzl, P; Rogers, M J; Klaushofer, K

2013-12-01

224

Predisposing factors to severe external root resorption associated to orthodontic treatment  

Digital Repository Infrastructure Vision for European Research (DRIVER)

OBJECTIVE: The aim of this study was to evaluate predisposing factors among patients who developed moderate or severe external root resorption (Malmgren's grades 3 and 4), on the maxillary incisors, during fixed orthodontic treatment in the permanent dentition. METHODS: Ninety-nine patients who underwent orthodontic treatment with fixed edgewise appliances were selected. Patients were divided into two groups: G1 - 50 patients with no root resorption or presenting only apical irregularities (M...

Gracemia Vasconcelos Picanço; Karina Maria Salvatore de Freitas; Rodrigo Hermont Cançado; Fabricio Pinelli Valarelli; Paulo Roberto Barroso Picanço; Camila Pontes Feijão

2013-01-01

225

Ion transporters involved in acidification of the resorption lacuna in osteoclasts  

DEFF Research Database (Denmark)

Osteoclasts possess a large amount of ion transporters, which participate in bone resorption; of these, the vacuolar-adenosine trisphosphatase (V-ATPase) and the chloride-proton antiporter ClC-7 acidify the resorption lacuna. However, whether other ion transporters participate in this process is currently not well understood. We used a battery of ion channel inhibitors, human osteoclasts, and their subcellular compartments to perform an unbiased analysis of the importance of the different ion transporters for acidification of the resorption lacuna in osteoclasts. CD14(+) monocytes from human peripheral blood were isolated, and mature osteoclasts were generated using RANKL and M-CSF. The human osteoclasts were (1) used for acridine orange assays for evaluation of lysosomal acidification, (2) used for bone resorption assays, (3) used for generation of osteoclasts membranes for acid influx experiments, or (4) lysed in trizol for mRNA isolation for Affymetrix array analysis. Inhibitors targeted toward most of theion transporters showed low potency in the acidification-based assays, although some inhibitors, such as carbonic anhydrase II and the sodium-hydrogen exchanger (NHE) inhibitors, reduced resorption potently. In contrast, inhibitors targeted at V-ATPase and ClC-7 potently inhibited both acidification and resorption, as expected. We here show evidence that acidification of the resorption lacuna is mainly mediated by V-ATPase and ClC-7. Furthermore, a group of other ion transporters, including carbonic anhydrase II, the NHEs, and potassium-chloride cotransporters, are all involved in resorption but do not seem to directly be involved in acidification of the lysosomes Udgivelsesdato: 2008/9

Henriksen, K.; Sorensen, M.G.

2008-01-01

226

Effects of berberine on differentiation and bone resorption of osteoclasts derived from rat bone marrow cells  

Directory of Open Access Journals (Sweden)

Full Text Available Objective: To observe the effects of berberine on osteoclastic differentiation and bone resorption action in vitro, and to investigate the cellular mechanism of its inhibitory effects on bone resorption.Methods: The multinucleated osteoclasts (MNCs were derived by 1,25-dihydroxyvitamin D3 and dexamethasone from bone marrow cells in the coculture system with primary osteoblastic cells. The tartrate-resistant acid phosphatase (TRAP staining and image analysis of bone resorption pit on dental slices were used to identify osteoclast. The activity of TRAP was measured by p-nitrophenyl sodium phosphate assay. The bone resorption pit area on the bone slices formed by osteoclasts was measured by computer image processing.Results: At the concentrations of 0.1, 1 and 10 ?mol/L, berberine dose-dependently suppressed the formation of TRAP-positive multinucleated cells, the TRAP activity and the osteoclastic bone resorption. The strongest inhibitory effect was exhibited at the concentration of 10 ?mol/L, with the inhibiting rate of 60.45%, 42.12% and 72.69% respectively.Conclusion: Berberine can decrease bone loss through inhibition of osteoclast formation, differentiation and bone resorption.

Peng WEI

2009-04-01

227

External root resorption after orthodontic treatment: a study of contributing factors  

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The purpose of this study was to examine the patient- and treatment-related etiologic factors of external root resorption. This study consisted of 163 patients who had completed orthodontic treatments and taken the pre- and post-treatment panoramic and lateral cephalometric radiographs. The length of tooth was measured from the tooth apex to the incisal edge or cusp tip on the panoramic radiograph. Overbite and overjet were measured from the pre- and post-treatment lateral cephalometric radiographs. The root resorption of each tooth and the factors of malocclusion were analyzed with an analysis of variance. A paired t test was performed to compare the mean amount of root resorption between male and female, between extraction and non-extraction cases, and between surgery and non-surgery groups. Correlation coefficients were measured to assess the relationship between the amount of root resorption and the age in which the orthodontic treatment started, the degree of changes in overbite and overjet, and the duration of treatment. Maxillary central incisor was the most resorbed tooth, followed by the maxillary lateral incisor, the mandibular central incisor, and the mandibular lateral incisor. The history of tooth extraction was significantly associated with the root resorption. The duration of orthodontic treatment was positively correlated with the amount of root resorption. These findings show that orthodontic treatment should be carefully performed in patients who need the treatment for a long period and with a pre-treatment extraction of teeth.

Jung, Yun Hoa; Cho, Bong Hae [School of Dentistry, Pusan National University, Pusan (Korea, Republic of)

2011-03-15

228

External root resorption after orthodontic treatment: a study of contributing factors  

International Nuclear Information System (INIS)

The purpose of this study was to examine the patient- and treatment-related etiologic factors of external root resorption. This study consisted of 163 patients who had completed orthodontic treatments and taken the pre- and post-treatment panoramic and lateral cephalometric radiographs. The length of tooth was measured from the tooth apex to the incisal edge or cusp tip on the panoramic radiograph. Overbite and overjet were measured from the pre- and post-treatment lateral cephalometric radiographs. The root resorption of each tooth and the factors of malocclusion were analyzed with an analysis of variance. A paired t test was performed to compare the mean amount of root resorption between male and female, between extraction and non-extraction cases, and between surgery and non-surgery groups. Correlation coefficients were measured to assess the relationship between the amount of root resorption and the age in which the orthodontic treatment started, the degree of changes in overbite and overjet, and the duration of treatment. Maxillary central incisor was the most resorbed tooth, followed by the maxillary lateral incisor, the mandibular central incisor, and the mandibular lateral incisor. The history of tooth extraction was significantly associated with the root resorption. The duration of orthodontic treatment was positively correlated with the amount of root resorption. These findings show that orthodontic treatment should be carefully performed in patients who need the treatment for a long period and with a pre-treatment extraction of teeth.

229

Rat spontaneous foetal resorption: altered ?2-macroglobulin levels and uNK cell number.  

Science.gov (United States)

During rat pregnancy, some of the foetoplacental units undergo complete spontaneous resorption while the adjacent units remain unaffected. In an attempt to clarify the mechanisms implicated in this spontaneous resorption, implantation units from days 14 and 16 of pregnancy were examined. The number of implantation sites and resorption units was recorded, and uterine paraffin sections were stained with haematoxylin and eosin for the evaluation of tissue morphology. The incidence of resorption was about 9.2 % on day 14 and 8.2 % on day 16. Perforin and active caspase-3 immunostaining were performed for localization and characterization of uterine natural killer (uNK) and apoptotic cells, respectively. The ?2-macroglobulin (?2-MG) expression was examined by in situ hybridization, immunohistochemistry and its levels quantified by enzyme-linked immunosorbent assay. A reduction in ?2-MG decidual levels in resorpted units was observed when compared to normal implantation units in both days. This potent protease inhibitor is the major product secreted by the mesometrial decidual tissue and may constitute an indicator of maternal tissues remodelling abnormalities. Besides the decreased ?2-MG levels, an increase in uNK cell number was found in resorption units. The decreased ?2-MG levels may be related to the aberrant control of trophoblast invasion that may activate uNK cells. The elucidation of the mechanisms underlying natural pregnancy loss in rat may contribute for the clarification of the "vanishing twin" phenomenon that occurs in human pregnancy. PMID:25085343

Fonseca, B M; Almada, M; Costa, M A; Teixeira, N A; Correia-da-Silva, G

2014-12-01

230

Adrenomedullin promotes lung angiogenesis, alveolar development, and repair.  

Science.gov (United States)

Bronchopulmonary dysplasia (BPD) and emphysema are significant global health problems at the extreme stages of life. Both are characterized by alveolar simplification and abnormal distal airspace enlargement due to arrested development or loss of alveoli, respectively. Both lack effective treatments. Mechanisms that inhibit distal lung growth are poorly understood. Adrenomedullin (AM), a recently discovered potent vasodilator, promotes angiogenesis and has protective effects on the cardiovascular and respiratory system. Its role in the developing lung is unknown. We hypothesized that AM promotes lung angiogenesis and alveolar development. Accordingly, we report that lung mRNA expression of AM increases during normal alveolar development. In vivo, intranasal administration of the AM antagonist, AM22-52 decreases lung capillary density (12.4 +/- 1.5 versus 18 +/- 1.5 in control animals; P alveolar development (mean linear intercept, 52.3 +/- 1.5 versus 43.8 +/- 1.8 [P alveolar growth, AM attenuates arrested lung angiogenesis (vessel density, 6.9 +/- 1.1 versus 16.2 +/- 1.3, P alveolar development (mean linear intercept, 51.9 +/- 3.2 versus 44.4 +/- 0.7, septal counts 47.6 +/- 3.4 versus 67.7 +/- 4.0, P alveolar development. AM may have therapeutic potential in diseases associated with alveolar injury. PMID:19738161

Vadivel, Arul; Abozaid, Sameh; van Haaften, Tim; Sawicka, Monika; Eaton, Farah; Chen, Ming; Thébaud, Bernard

2010-08-01

231

Alveolar epithelial cells: master regulators of lung homeostasis.  

Science.gov (United States)

The lung interfaces with the environment across a continuous epithelium composed of various cell types along the proximal and distal airways. At the alveolar structure level, the epithelium, which is composed of type I and type II alveolar epithelial cells, represents a critical component of lung homeostasis. Indeed, its fundamental role is to provide an extensive surface for gas exchange. Additional functions that act to preserve the capacity for such unique gas transfer have been progressively identified. The alveolar epithelium represents a physical barrier that protects from environmental insults by segregating inhaled foreign agents and regulating water and ions transport, thereby contributing to the maintenance of alveolar surface fluid balance. The homeostatic role of alveolar epithelium relies on the regulated/controlled production of the pulmonary surfactant, which is not only a key determinant of alveolar mechanical stability but also a complex structure that participates in the cross-talk between local cells and the lung immune and inflammatory response. In regard to these critical functions, a major point is the maintenance of alveolar surface integrity, which relies on the renewal capacity of type II alveolar epithelial cells, and the contribution of progenitor populations within the lung. PMID:23988571

Guillot, Loïc; Nathan, Nadia; Tabary, Olivier; Thouvenin, Guillaume; Le Rouzic, Philippe; Corvol, Harriet; Amselem, Serge; Clement, Annick

2013-11-01

232

Frequency and distribution of palatal osseous alveolar marginal exostoses--POAMES.  

Science.gov (United States)

1,272 human skulls were examined for frequency and distribution of POAMES--palatal osseous alveolar marginal exostoses. The sample consisted of Blacks, Mixed, Whites and Chinese as well as adult edentulous and dentate child skulls. POAMES were most prevalent between 35 and 45 years of age, appeared most commonly in the maxillary third molar region, followed by the second and first molar region, occurred most frequently bilateraly and were least prevalent in Blacks. The overall prevalence of POAMES was 14.5 per cent with a female to male ratio of 1:3,5. Ridge POAMES occurred most frequently, followed by combined, ledge and the nodular exostose types. It did not occur in children or edentulous adults. PMID:1820682

Touyz, L Z; Tau, S

1991-09-01

233

Demineralized bone matrix for alveolar cleft management.  

Science.gov (United States)

The aim of this article is to describe the results of the use of demineralized bone matrix putty in alveolar cleft of patients with cleft lip and palate. We performed a prospective, descriptive case series study, in which we evaluated the results of the management of alveolar clefts with demineralized bone matrix. Surgery was performed in 10 patients aged between 7 and 26 years (mean 13 years), involving a total of 13 clefts in the 10 patients. A preoperative cone beam computed tomography (CBCT) was taken to the patients in whom the width of the cleft was measured from each edge of the cleft reporting values between 5.76 and 16.93?mm (average, 11.18 mm). The densities of the clefts were measured with a CBCT, 6 months postoperative to assess bone formation. The results showed a register of gray values of 1,148 to 1,396 (mean, 1,270). The follow-up was conducted for 15 to 33 months (mean, 28.2 months). The results did not show satisfactory bone formation in the cleft of patients with the use of demineralized bone matrix. PMID:25383144

Madrid, Jose Rolando Prada; Gomez, Viviana; Mendoza, Bibiana

2014-12-01

234

Adult alveolar rhabdomyosarcoma of the lacrimal sac.  

Science.gov (United States)

Abstract Lacrimal sac tumours are rare, but must be considered in the diagnosis of patients presenting with masses in the medial canthal region. We report a single case of lacrimal sac rhabdomyosarcoma in a 31-year-old man. The patient self-presented to the eye department with a 4-week history of discomfort, epiphora and a medial canthal mass. After no response to 1 week of oral antibiotics for a presumed diagnosis of dacryocystitis and the presence of firm mass extending above the medial canthal tendon, surgical exploration was carried out which revealed a lacrimal sac mass. Histologically this showed an alveolar rhabdomyosarcoma, which was confirmed on immunohistochemistry. After 4 rounds of chemotherapy and 50.4Gy of radical radiotherapy, the patient is well with no signs of further local or distant disease at 11-months follow-up and 20 months following initial diagnosis. To our knowledge, there are no previously reported adult cases of lacrimal sac alveolar rhabdomyosarcoma in the peer-reviewed literature. We want to highlight the unique diagnosis in this case as well as drawing attention to the possibility of malignancy in patients responding poorly to management when an initial diagnosis of dacryocystitis is made in the presence of a medial canthal mass. PMID:25207922

Neffendorf, James E; Bagdonaite, Laura; Mudhar, Hardeep S; Pearson, Andrew R

2014-12-01

235

Consideraciones anatómicas del conducto alveolar inferior / Anatomical considerations of the inferior alveolar canal  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish INTRODUCCIÓN: el conocimiento de variantes anatómicas del conducto alveolar inferior es necesario para la realización de procedimientos que involucren la mandíbula. El objetivo fue determinar las relaciones y variaciones anatómicas del conducto alveolar inferior MÉTODOS: se hizo un estudio descripti [...] vo, en 50 hemimandíbulas humanas secas, midiendo distancias del foramen mandibular con respecto a los bordes anterior, posterior, inferior y escotadura sigmoidea, las distancias del agujero mentoniano al borde basal y la cresta alveolar. Se hicieron cortes en la rama y el cuerpo, para determinar las relaciones con estructuras anatómicas próximas. RESULTADOS: el foramen mandibular fue encontrado en el 88% en el tercio medio de rama. La distancia del foramen a la escotadura fue 19,78 ± 3,3 mm, al borde anterior 17,46 ± 3,04, al borde posterior 12,2 ± 1,9 y al borde basal 26,4 ± 3,8 mm. La ubicación del conducto alveolar inferior a nivel de rama respecto a los bordes anterior, posterior, lateral y medial fue 11,1 ± 2,6, 15,8 ± 2,7, 3,5 ± 1,0 y 1,9 ± 0,7 mm respectivamente. En el cuerpo mandibular la distancias respecto a los bordes basal, lateral, medial y alveolar fueron 10,1 ± 2,3, 4,7 ± 1,4, 2,5 ± 1,0 y 13,7 ± 2,7 mm respectivamente distal al tercer molar, 7,6 ± 1,7, 6,4 ± 1,4, 2,8 ± 1,0 y 16,4 ± 2,2 mm distal al segundo molar, 7,1 ± 1,5, 6,1 ± 1,3, 2,6 ± 0,8 y 17,0 ± 2,3 mm distal al primer molar, y 7,9 ± 1,7, 4,7 ± 1,2, 3,4 ± 1,2 y 18.3±2.7 mm distal al segundo premolar. El diámetro fue 2,82 ± 0,6 mm. La distancia del agujero mentoniano al borde basal fue 14,2 ± 1,59 mm, a la cresta alveolar 15,97 ± 2,87 mm, y se relacionó con el segundo premolar. CONCLUSIONES: los datos obtenidos, si bien, no infieren en la totalidad de la población colombiana, confirma que existen variaciones anatómicas del conducto alveolar inferior diferentes a las descritas en otras poblaciones. Abstract in english INTRODUCTION: the knowledge of anatomical variations of the inferior alveolar canal is necessary for surgical procedures involving the mandible. The purpose was to determine the relationships and anatomical variations of the mandibular canal. METHODS: a descriptive study was performed using 50 dry m [...] andibles measuring distances of the mandibular foramen with respect to the anterior posterior and lower borders and the sigmoid notch, distances from the mental foramen to the basal border and the alveolar crest. Cuts were done in ramus and body to determine the relationship with close anatomical structures. RESULTS: The mandibular foramen was found in 88% of the cases in the middle third of ramus. The distance from the foramen to the sigmoid notch was 19.78 ± 3.3 mm, to the anterior border was 17.46 ± 3.04 mm, to the posterior border was 12.2 ± 1.9 mm and to the inferior border was 26.4 ± 3.8 mm. The location of the inferior alveolar canal on the mandibular ramus with respect to the anterior, posterior, lateral and medial borders were 11.1 ± 2.6 mm, 15.8 ± 2.7 mm, 3.5 ±1.0 mm y 1.9 ± 0.7 mm respectively. On the mandibular body, the distances from the inferior alveolar canal to the inferior, lateral, medial and alveolar borders were 10.1 ± 2.3 mm, 4.7 ± 1.4 mm, 2.5 ± 1.0 mm and 13.7±2.7 mm respectively distal to the third molar, 7.6 ± 1.7 mm, 6.4 ± 1.4 mm, 2.8 ± 1.0 mm and 16.4 ± 2.2 mm distal to the second molar, 7.1 ± 1.5 mm, 6.1 ± 1.3 mm, 2.6 ± 0.8 mm and 17.0 ± 2.3 mm distal to the first molar, and 7.9 ± 1.7 mm, 4.7 ± 1.2 mm, 3.4 ± 1.2 mm and 18.3 ± 2.7 mm distal to the second bicuspid. The diameter was 2.82 ± 0.6 mm. The distance from the mental foramen to the inferior border was 14.2 ± 1.59 mm, to the alveolar crest was 15.97 ± 2.87 mm, and it was directly related to the second bicuspid. CONCLUSIONS: The data obtained, even though, do not infer in the totality of the Colombian population, confirms that there are anatomical variations of the inferior alveolar canal different from the ones

Omar Yamid, Ruge Jiménez; Oscar Andrés, Camargo Cañón; Yudy, Patricia Ortiz.

236

Oak Ridge national reservation  

International Nuclear Information System (INIS)

The US Department of Energy (DOE) Oak Ridge Reservation is located on 37 000 acres in east Tennessee. The Oak Ridge facilities include the Oak Ridge National Laboratory (ORNL), the Y-12 National Security Complex and the East Tennessee Technology Park (ETTP - originally built as a uranium enrichment facility for defence programmes and originally named 'The Oak Ridge Gaseous Diffusion Plant'. After World War II this plant was renamed Oak Ridge K-25 Site and produced enriched uranium for the commercial nuclear power industry from 1945 to 1985. It was renamed ETTP in 1987. The situation at this site is characterized by hundreds of contaminated buildings in deteriorating conditions. The water table is shallow at the site implying a short travel time of the contaminants. The overall strategy for cleanup of the Reservation is based on surface water considerations as the Reservation encompasses five distinct watersheds. The cleanup strategy is a risk-based approach that focuses first on those contaminant sources that are the greatest contributors of risk. The watershed approach is used to determine which sources are the worst contributors and therefore should be cleaned up as early as possible. At the end of site cleanup, planned by 2015, the Oak Ridge National Laboratory will continue to operate as a world-class research facility. Y-12 will continue to operate, fulfilling its national security mission. As cleanup of the East Tennessee Technology Park is completed DOE will tre Technology Park is completed DOE will transfer ownership of the uncontaminated buildings to the Community Reuse Organization of East Tennessee (CROET) which in turn will lease this property for immediate private industrial use. To further refine the overall cleanup strategy, a prioritization system has been developed to help guide decisions where investments should be made. The general priorities are as follows: (a) Mitigate immediate onsite and offsite risks; (b) Reduce offsite migration of contaminants; (c) Remediate sources of surface water and groundwater contamination; (d) Remediate remaining onsite contamination; (e) Demolish excess facilities

237

External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation  

International Nuclear Information System (INIS)

This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39±1.27 (8.24±7.22%) and 1.69±1.14 mm (10.16±6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

238

Age-related changes in resorption cavity characteristics in human trabecular bone.  

Science.gov (United States)

The depth of resorption cavities in trabecular bone is an important determinant of bone structure and has implications relevant to the cellular pathophysiology of bone loss in osteoporosis. However, assessment of resorption depth has proved difficult and few data are available; in this study we report age-related changes in iliac crest trabecular bone obtained from 41 normal healthy subjects (21 female, 20 male) aged 22-80 years. Using 8-microns undecalcified sections stained with toluidine blue, resorption cavities were quantitatively assessed by a computerized technique in which the eroded bone surface is reconstructed and measurements made interactively. Maximum and mean cavity depth showed no significant correlation with age in either sex. The absolute length of eroded surface was unrelated to age but the eroded surface/BS (%) and the number of cavities/BS (/mm) showed a significant positive correlation with age (r = 0.384 and 0.386 respectively, p less than 0.05). No significant correlation was found between age and either cavity area or density. These results suggest that increased resorption depth does not contribute to age-related bone loss, although the possibility that deeper resorption cavities occur which result in trabecular penetration and are therefore unrecognizable cannot be discounted. The age-related increase in eroded surface/BS (%) reflects a decreased available trabecular surface and/or increased number of cavities rather than a greater surface length of individual cavities; alternatively it may indicate an increased resorption period. No evidence of increased resorption depth at the time of the menopause was found in this study. PMID:1790413

Croucher, P I; Garrahan, N J; Mellish, R W; Compston, J E

1991-09-01

239

External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation  

Energy Technology Data Exchange (ETDEWEB)

This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39{+-}1.27 (8.24{+-}7.22%) and 1.69{+-}1.14 mm (10.16{+-}6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

Nanekrungsan, Kamonporn [Dept. of Dentistry, Overbrook Hospital, Chiang Rai (Thailand); Patanaporn, Virush; Janhom, Apirum; Korwanich, Narumanus [Dept. of Chiang Mai University, Chiang Mai (Thailand)

2012-09-15

240

Endostatin inhibits VEGF-A induced osteoclastic bone resorption in vitro  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Endostatin is a C-terminal fragment of collagen XVIII which is a component of basement membranes with the structural properties of both collagens and proteoglycans. Endostatin has a major role in angiogenesis which is intimately associated with bone development and remodeling. Signaling between the endothelial cells and the bone cells, for example, may have a role in recruitment of osteoclastic precursor cells. Our study aims at exploring a possibility that endostatin, either as a part of basement membrane or as a soluble molecule, may control osteoclastogenesis and osteoclastic bone resorption in vitro. Methods Rat pit formation assay was employed in order to examine the effect of endostatin alone or in combination with vascular endothelial growth factor-A (VEGF-A on bone resorption in vitro. Effect of these agents on osteoclast differentiation in vitro was also tested. Osteoclastogenesis and the number of osteoclasts were followed by tartrate resistant acid phosphatase (TRACP staining and resorption was evaluated by measuring the area of excavated pits. Results Endostatin inhibited the VEGF-A stimulated osteoclastic bone resorption, whereas endostatin alone had no effect on the basal resorption level in the absence of VEGF-A. In addition, endostatin could inhibit osteoclast differentiation in vitro independent of VEGF-A. Conclusion Our in vitro data indicate that collagen XVIII/endostatin can suppress VEGF-A induced osteoclastic bone resorption to the basal level. Osteoclastogenesis is also inhibited by endostatin. The regulatory effect of endostatin, however, is not critical since endostatin alone does not modify the basal bone resorption.

Ilvesaro Joanna

2006-07-01

 
 
 
 
241

Resorption Rate Tunable Bioceramic: Si, Zn-Modified Tricalcium Phosphate  

Energy Technology Data Exchange (ETDEWEB)

This dissertation is organized in an alternate format. Several manuscripts which have already been published or are to be submitted for publication have been included as separate chapters. Chapter 1 is a general introduction which describes the dissertation organization and introduces the human bone and ceramic materials as bone substitute. Chapter 2 is the background and literature review on dissolution behavior of calcium phosphate, and discussion of motivation for this research. Chapter 3 is a manuscript entitled ''Si,Zn-modified tricalcium phosphate: a phase composition and crystal structure study'', which was published in ''Key Engineering Materials'' [1]. Chapter 4 gives more crystal structure details by neutron powder diffraction, which identifies the position for Si and Zn substitution and explains the stabilization mechanism of the structure. A manuscript entitled ''Crystal structure analysis of Si, Zn-modified Tricalcium phosphate by Neutron Powder Diffraction'' will be submitted to Biomaterials [2]. Chapter 5 is a manuscript, entitled ''Dissolution behavior and cytotoxicity test of Si, Zn-modified tricalcium phosphate'', which is to be submitted to Biomaterials [3]. This paper discusses the additives effect on the dissolution behavior of TCP, and cytotoxicity test result is also included. Chapter 6 is the study of hydrolysis process of {alpha}-tricalcium phosphate in the simulated body fluid, and the phase development during drying process is discussed. A manuscript entitled ''Hydrolysis of {alpha}-tricalcium phosphate in simulated body fluid and phase transformation during drying process'' is to be submitted to Biomaterials [4]. Ozan Ugurlu is included as co-authors in these two papers due to his TEM contributions. Appendix A is the general introduction of the materials synthesis, crystal structure and preliminary dissolution result. A manuscript entitled ''Resorption rate tunable bioceramic: Si and Zn-modified tricalcium phosphate'' was published in Ceramic Engineering and Science Proceedings (the 29th International Conference on Advanced Ceramics and Composites - Advances in Bioceramics and Biocomposites) [5].

Xiang Wei

2006-08-09

242

Measurements of alveolar concentrations of toluene.  

Science.gov (United States)

The use of a photoionisationdetector (PID) for measurement of alveolar concentrations of gases and vapours was evaluated during a human exposure experiment with toluene. Two other methods, the standard gaspipette method and the gasbag /charcoal method, was tested for comparison. The best method appeared to be the PID-method. The major disadvantage in using this instrument was the missing selectivity towards individual compounds in a mixed atmosphere. In all other respects, the method is just as good as or better than the standard gaspipette method and the gasbag method. Results from 40 measurements with the three methods on 16 persons were examined statistically, and the average toluene absorption at 100 ppm exposure levels was estimated to be 1.6 mg/min. PMID:6724703

Mølhave, L; Pedersen, O F

1984-01-01

243

Diffuse alveolar hemorrhage due to ketorolac tromethamine.  

Science.gov (United States)

Drug-induced lung disease (DILD) is a common but frequently missed diagnosis. Therefore, a high index of clinical suspicion and familiarity with the clinical syndromes associated with DILD are important in making the diagnosis. Nonsteroidal anti-inflammatory drugs (NSAIDs) are one of the mostly commonly used classes of medications. NSAIDs are safe when used at prescribed doses. Side effects from use of NSAIDs are not uncommon and can affect almost every organ system in the body. NSAIDs are notorious for causing pulmonary toxicity, the common ones being bronchospasm and hypersensitivity reactions. Diffuse alveolar hemorrhage (DAH) secondary to NSAIDs is uncommon. Here, we report a case of DAH secondary to the use of ketorolac tromethamine. PMID:23867384

Marak, Creticus P; Alappan, Narendrakumar; Shim, Chang; Guddati, Achuta K

2013-01-01

244

Ridge from Strings  

CERN Document Server

In the colour string picture with fusion and percolation it is shown that long range azimuthal-rapidity correlations (ridge) can arise from the superposition of many events with exchange of clusters of different number of strings and not from a single event. Relation of the ridge with the flow harmonics coefficients is derived. By direct Monte-Carlo simulations, in the technique previously used to calculate these coefficients, ridge correlations are calculated for AA, pA and pp collisions. The azimuthal anisotropy follows from the assumed quenching of the emitted particles in the strong colour fields inside string clusters. It is confirmed that in pp collisions the ridge structure only appears in rare events with abnormally high multiplicity. Comarison with the experimental data shows a good agreement. Also a good agreement is found for pPb collisions. For AA collisions a reasonable agreement is found for both near-side and away-side angular correlations although it worsens at intermediate angles.

Braun, M A; Vechernin, V V

2014-01-01

245

Treatment of maxillary central incisor with external root resorption using mineral trioxide aggregate: 18 months follow-up.  

Science.gov (United States)

External cervical resorption is the loss of dental hard tissue as a result of odontoclastic action; it usually begins on the cervical region of the root surface of the teeth. This case report demonstrates an external cervical resorption in a maxillary central incisor of a 24-year-old male patient. After surgical intervention and root canal treatment, the resorption was subsequently sealed with mineral trioxide aggregate. The 18 months follow-up demonstrates no pathological changes on clinical and radiographic examination. This case report presents a treatment strategy that might improve the healing outcomes for patients with external cervical resorption. PMID:23843419

Gandi, Padma; Disha, Saraswathi

2013-01-01

246

The effects of the cathepsin K inhibitor odanacatib on osteoclastic bone resorption and vesicular trafficking.  

Science.gov (United States)

Odanacatib (ODN) is a selective, potent and reversible inhibitor of cathepsin K (CatK) that inhibits bone loss in postmenopausal osteoporosis. Evidence from osteoclast (OC) formation from bone marrow of CatK(-/-) mice or human OC progenitors treated with ODN, demonstrated that CatK inhibition has no effect on osteoclastogenesis or survival of OCs. Although having no impact on OC activation, ODN reduces resorption activity as measured by CTx release (IC(50)=9.4 nM) or resorption area (IC(50)=6.5 nM). While untreated cells generate deep trail-like resorption lacunae, treated OCs form small discrete shallow pits. ODN leads to significant accumulation of intracellular vesicles intensely stained for CatK and TRAP. CatK (+) vesicles localize toward the basolateral and functional secretory membranes of the polarized OC and TRAP(+) vesicles evenly distribute in the cytoplasm, suggesting that ODN disrupts multiple vesicular trafficking pathways. Intracellular levels of both precursor and mature TRAP were increased by 2-fold and the pre-pro and mature CatK by 6- and 2-fold in ODN-treated OCs compared to untreated controls. ODN treated OC accumulates labeled degraded bone matrix proteins in CatK containing vesicles. In summary, ODN treatment inhibits bone resorption by blocking degradation of demineralized collagen in the resorption lacunae, and retarding transcytosis for further processing of degraded proteins. PMID:21718816

Leung, P; Pickarski, M; Zhuo, Y; Masarachia, P J; Duong, L T

2011-10-01

247

Expression of RANKL mRNA during Root Resorption Induced by Orthodontic Tooth Movement in Rats  

Directory of Open Access Journals (Sweden)

Full Text Available Objective: Receptor activator for nuclear factor kappa B ligand (RANKL, which is alsocalled osteoclast differentiation factor, is an important regulatory factor in osteoclastmaturation. Knowledge of bone and cementum similarities and RANKL role in bone resorptionsuggests the possibility of a role for this protein in root resorption induced by orthodontictooth movement. The aim of this study is to examine the expression of RANKLmRNA during root resorption induced by orthodontic tooth movement in rats.Materials and Methods: In order to move maxillary right first molars mesially fixed Ni-Ticlosed coil springs (Dentaurum®-Germany were tightened to the teeth. Sample consistedof 20 male seven week old Wistar rats. For each animal, the contralateral tooth was usedas, an internal control. At day 21 the rats were sacrificed. Tissues from 10 rats were embeddedin paraffin for histologic examination. Scratched material from resorptive lacunaeon mesial sides of the roots of the other ten rats was used for extracting mRNA by RTPCR.Results: The histologic sections, analyzed histomorphometrically, showed a significantincrease in root resorption in the case group as compared to the control (p<0.001.Densitometric studies of RANKL mRNA expression band on gel electrophoresis showedsignificantly increased RANKL expression in the resorptive lacunae of the case group(p<0.001.Conclusion: This observation indicates increased RANKL

Massoud Seifi

2009-01-01

248

Apical root resorption of maxillary first molars after intrusion with zygomatic skeletal anchorage.  

Science.gov (United States)

The aim of this study was to evaluate radiographically the apical root resorption of maxillary first molars after their intrusion was done using zygomatic miniplates as skeletal anchorage in open-bite cases. The study group comprised 16 consecutively treated open-bite cases who had received special titanium miniplates in their zygomatic bones for use as anchorage to apply orthodontic intrusive forces to the maxillary posterior region. The control group consisted of 16 patients, who were matched regarding age, sex, and treatment duration but who had undergone fixed orthodontic treatment without intrusion mechanics for molars. Tooth lengths were measured on pretreatment, and posttreatment panoramic radiographs of all patients and mesiobuccal and distobuccal roots of left and right maxillary first molars were measured on-screen using a software program. The difference between the pre- and posttreatment tooth lengths was defined as apical root resorption. Comparison of the differences in root resorption of the two groups using the t-test for independent samples showed a statistically significant difference (P = .004) only for mesial roots on the right side. But because the mean difference in apical root resorption was only 0.5 mm, it was concluded that the apical root resorption of maxillary first molars after intrusion was done using zygomatic skeletal anchorage was not clinically significant. PMID:16283814

Ari-Demirkaya, Arzu; Masry, Mazin Al; Erverdi, Nejat

2005-09-01

249

Effects of intrusion combined with anterior retraction on apical root resorption.  

Science.gov (United States)

This study evaluated the influence of intrusion mechanics combined with anterior retraction on root resorption of the maxillary incisors. A sample of 56 patients was divided into two groups: group 1 comprised 28 patients (12 females and 16 males), presenting with an increased overjet and deep overbite (6.48 and 4.78 mm, respectively) treated with reverse curve of Spee intrusion mechanics and group 2 comprised 28 patients (12 females and 16 males) with an increased overjet of 5.67 mm and a normal overbite of 1.12 mm. The initial mean ages for groups 1 and 2 were 13.41 and 13.27 years, respectively. Pre- (T1) and post- (T2) treatment periapical radiographs were used to evaluate root resorption. The groups were compared using the Mann-Whitney U-test. Correlation between root resorption and tooth movement was investigated with Spearman's correlation coefficient. The subjects in group 1 had statistically greater root resorption (P intrusive mechanics causes more root resorption than anterior retraction of the maxillary incisors alone. PMID:21389075

Martins, Décio Rodrigues; Tibola, Douglas; Janson, Guilherme; Maria, Fábio Rogério Torres

2012-04-01

250

colour leaflet of gravel ridge island assi  

...I SA AI S Gravel Ridge Island has been declared as...colony of Sandwich Tern. Gravel Ridge Island is a small gravel...to maintain and enhance Gravel Ridge Island ASSI. GRAVEL RIDGE A SPISLECIAL ANDPLACE... A view...

251

Proteinose alveolar pulmonar: série de quatro casos / Pulmonary alveolar proteinosis: four cases  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Apresentar a evolução de quatro casos de proteinose alveolar pulmonar atendidos na Faculdade de Medicina da Universidade Estadual de Londrina, enfocando a importância da lavagem pulmonar total como tratamento de escolha. MÉTODOS: Trata-se de um estudo retrospectivo de quatro pacientes, sen [...] do três do gênero feminino, com idades de 22 a 34 anos, e histórias semelhantes de dispnéia progressiva e tosse seca. O diagnóstico final foi realizado por biópsia pulmonar a céu aberto. A lavagem pulmonar total foi realizada em três pacientes em centro cirúrgico, com anestesia geral e sonda de duplo lúme. RESULTADOS: Um paciente apresentou regressão espontânea da proteinose alveolar pulmonar, não sendo necessária a lavagem pulmonar. Nos outros três casos, o número de lavagens variou: uma única lavagem unilateral com remissão completa do quadro bilateralmente, três lavagens sem melhora significativa e quatro procedimentos intercalados com períodos de melhora. CONCLUSÃO: Constatamos em nossa casuística que a lavagem pulmonar se mostrou eficiente, apesar de alguns pacientes apresentarem certa resistência ao procedimento, enquanto que outros podem ter remissão completa da doença. Abstract in english OBJECTIVE: The aim of this study was to present the evolution of four patients presenting pulmonary alveolar proteinosis and treated at the State University of Londrina School of Medicine. We focus on the importance of whole-lung lavage as the treatment of choice. METHODS: A retrospective study of f [...] our patients, three females and one male, 22 to 34 years old, presenting similar histories of progressive dyspnea and dry cough. The final diagnosis was established through open-lung biopsy. Three of the patients underwent whole-lung lavage in the Department of Surgery. The procedures were performed under general anesthesia and using a double-lumen endotracheal tube. RESULTS: One patient presented spontaneous regression of the pulmonary alveolar proteinosis without the need for whole-lung lavage. In the other three cases, the number of lavages varied: in one patient, a single unilateral lavage resulted in complete remission of the bilateral process; in another patient, three lavages yielded no significant improvement; in the remaining patient, four lavages provided intervening periods of transient improvement. CONCLUSION: In the cases evaluated, whole-lung lavage proved an efficient treatment for pulmonary alveolar proteinosis. Although some patients presented a certain resistance to the procedure, it might lead to complete remission of the disease in others.

João Carlos, Thompson; Marina, Kishima; Mariana Ulbricht, Gomes; Mariano de Almeida, Menezes; José, Perandré Neto; Paula Tapia Gomes, Pereira.

2006-06-01

252

Proteinose alveolar pulmonar: série de quatro casos Pulmonary alveolar proteinosis: four cases  

Directory of Open Access Journals (Sweden)

Full Text Available OBJETIVO: Apresentar a evolução de quatro casos de proteinose alveolar pulmonar atendidos na Faculdade de Medicina da Universidade Estadual de Londrina, enfocando a importância da lavagem pulmonar total como tratamento de escolha. MÉTODOS: Trata-se de um estudo retrospectivo de quatro pacientes, sendo três do gênero feminino, com idades de 22 a 34 anos, e histórias semelhantes de dispnéia progressiva e tosse seca. O diagnóstico final foi realizado por biópsia pulmonar a céu aberto. A lavagem pulmonar total foi realizada em três pacientes em centro cirúrgico, com anestesia geral e sonda de duplo lúme. RESULTADOS: Um paciente apresentou regressão espontânea da proteinose alveolar pulmonar, não sendo necessária a lavagem pulmonar. Nos outros três casos, o número de lavagens variou: uma única lavagem unilateral com remissão completa do quadro bilateralmente, três lavagens sem melhora significativa e quatro procedimentos intercalados com períodos de melhora. CONCLUSÃO: Constatamos em nossa casuística que a lavagem pulmonar se mostrou eficiente, apesar de alguns pacientes apresentarem certa resistência ao procedimento, enquanto que outros podem ter remissão completa da doença.OBJECTIVE: The aim of this study was to present the evolution of four patients presenting pulmonary alveolar proteinosis and treated at the State University of Londrina School of Medicine. We focus on the importance of whole-lung lavage as the treatment of choice. METHODS: A retrospective study of four patients, three females and one male, 22 to 34 years old, presenting similar histories of progressive dyspnea and dry cough. The final diagnosis was established through open-lung biopsy. Three of the patients underwent whole-lung lavage in the Department of Surgery. The procedures were performed under general anesthesia and using a double-lumen endotracheal tube. RESULTS: One patient presented spontaneous regression of the pulmonary alveolar proteinosis without the need for whole-lung lavage. In the other three cases, the number of lavages varied: in one patient, a single unilateral lavage resulted in complete remission of the bilateral process; in another patient, three lavages yielded no significant improvement; in the remaining patient, four lavages provided intervening periods of transient improvement. CONCLUSION: In the cases evaluated, whole-lung lavage proved an efficient treatment for pulmonary alveolar proteinosis. Although some patients presented a certain resistance to the procedure, it might lead to complete remission of the disease in others.

João Carlos Thompson

2006-06-01

253

Proteinose alveolar pulmonar: série de quatro casos / Pulmonary alveolar proteinosis: four cases  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Apresentar a evolução de quatro casos de proteinose alveolar pulmonar atendidos na Faculdade de Medicina da Universidade Estadual de Londrina, enfocando a importância da lavagem pulmonar total como tratamento de escolha. MÉTODOS: Trata-se de um estudo retrospectivo de quatro pacientes, sen [...] do três do gênero feminino, com idades de 22 a 34 anos, e histórias semelhantes de dispnéia progressiva e tosse seca. O diagnóstico final foi realizado por biópsia pulmonar a céu aberto. A lavagem pulmonar total foi realizada em três pacientes em centro cirúrgico, com anestesia geral e sonda de duplo lúme. RESULTADOS: Um paciente apresentou regressão espontânea da proteinose alveolar pulmonar, não sendo necessária a lavagem pulmonar. Nos outros três casos, o número de lavagens variou: uma única lavagem unilateral com remissão completa do quadro bilateralmente, três lavagens sem melhora significativa e quatro procedimentos intercalados com períodos de melhora. CONCLUSÃO: Constatamos em nossa casuística que a lavagem pulmonar se mostrou eficiente, apesar de alguns pacientes apresentarem certa resistência ao procedimento, enquanto que outros podem ter remissão completa da doença. Abstract in english OBJECTIVE: The aim of this study was to present the evolution of four patients presenting pulmonary alveolar proteinosis and treated at the State University of Londrina School of Medicine. We focus on the importance of whole-lung lavage as the treatment of choice. METHODS: A retrospective study of f [...] our patients, three females and one male, 22 to 34 years old, presenting similar histories of progressive dyspnea and dry cough. The final diagnosis was established through open-lung biopsy. Three of the patients underwent whole-lung lavage in the Department of Surgery. The procedures were performed under general anesthesia and using a double-lumen endotracheal tube. RESULTS: One patient presented spontaneous regression of the pulmonary alveolar proteinosis without the need for whole-lung lavage. In the other three cases, the number of lavages varied: in one patient, a single unilateral lavage resulted in complete remission of the bilateral process; in another patient, three lavages yielded no significant improvement; in the remaining patient, four lavages provided intervening periods of transient improvement. CONCLUSION: In the cases evaluated, whole-lung lavage proved an efficient treatment for pulmonary alveolar proteinosis. Although some patients presented a certain resistance to the procedure, it might lead to complete remission of the disease in others.

João Carlos, Thompson; Marina, Kishima; Mariana Ulbricht, Gomes; Mariano de Almeida, Menezes; José, Perandré Neto; Paula Tapia Gomes, Pereira.

254

Treatment of multiple traumatized anterior teeth associated with an alveolar bone fracture in a 15-year-old school boy: a 2.5-year follow up.  

Science.gov (United States)

We report a case of multiple dental traumas in a 15-year-old school boy who was hit by a stone. Clinical examinations revealed the avulsion of teeth 21, 22, and 23, an uncomplicated crown fracture of tooth 41, and a complicated crown fracture (CCF) of teeth 11, 31, and 33. An alveolar bone fracture and a root fracture in the apical third of tooth 23 were as well noted on radiographs. The avulsed teeth were replanted and rigidly splinted after an extraoral dry time of 90 min. Endodontic treatments were performed on teeth with CCFs. The dental morphology was restored using polyethylene fiber-reinforced composite resin. Endodontic obturations were performed on replanted teeth after the arrest of external root resorptions by a long-term calcium hydroxide dressing. Esthetics and function were recovered with a 2.5-year follow-up period. PMID:21281442

Berrezouga, L; Kammoun, D; Bhouri, L; Alaya, Ben T; Belkhir, M S

2011-04-01

255

Clinical and histological evaluation of alloderm GBR and BioOss in the treatment of Siebert's class I ridge deficiency.  

Science.gov (United States)

Complete prosthetic rehabilitation using implants require the presence of adequate dimensions of alveolar bone. Ridge augmentation procedures include the use of guided bone regeneration (GBR) procedures where the barrier membrane provides cell occlusion and space for the regenerating tissues. Alloderm GBR has been introduced for the purpose of augmenting bone and has been postulated to have the additionally ability to integrate into soft tissues. Twenty-two patients with Siebert's class I ridge deficiency were treated with BioOss and Alloderm GBR and followed up for a period of nine months. Significant increase in ridge dimensions of both hard and soft tissues were observed at six months period itself, suggesting that it as an effective method of augmenting deficient ridges. PMID:20142949

Sudarsan, Sabitha; Arun, K V; Priya, M S; Arun, Ramya

2008-09-01

256

[Reducing bone resorption by cathepsin K inhibitor and treatment of osteoporosis].  

Science.gov (United States)

Cathepsin K is a lysosomal cysteine protease, secreted from osteoclasts. It plays a major role in the osteoclastic bone resorption by cleaving type 1 collagen, the major bone matrix protein, under acidic pH. In cathepsin K knockout mice, bone mineral density (BMD) is increased, bone resorption is decreased without reduction in the number of osteoclast whereas bone formation is decreased. Based on these results, cathepsin K inhibitors have been developed for the treatment of osteoporosis. Odanacatib is one of them and is perhaps closest for launching. In phase 1 and 2 trials, it markedly reduced bone resorption with a transient reduction in bone formation, thus resulted in a robust increase in both trabecular and cortical BMD in osteoporotics. Currently, Odanacatib is in phase 3 fracture prevention trial, of which results are anticipated in 2014. PMID:24369281

Watanabe, Reiko; Okazaki, Ryo

2014-01-01

257

A computerised technique for the quantitative assessment of resorption cavities in trabecular bone.  

Science.gov (United States)

A computerised technique is described for the quantitative assessment of resorption cavities in iliac trabecular bone. Using an Ibas II image analyser, the original bone surface, eroded by bone resorbing cells, is reconstructed using a curve fitting technique that maintains a smooth continuity with the trabecular bone on either side of the cavity. Resorption depths are measured using an interactive elastic circle; all identified cavities are measured regardless of whether or not resorption is complete, and the measurements made include mean and maximum cavity depth, cavity length, area, and adjacent trabecular widths. Results in 13 normal subjects are presented. The technique is reproducible, simple to operate, relatively rapid, and can be applied to less sophisticated image analysis systems. PMID:2242290

Garrahan, N J; Croucher, P I; Compston, J E

1990-01-01

258

Localized idiopathic apical root resorption: a report of five cases with emphasis on differential diagnosis.  

Science.gov (United States)

Seeking to describe the clinical and radiologic features of localized idiopathic apical root resorption (LIAR), the authors conducted a dental literature review of idiopathic external root resorption and performed a retrospective study of LIAR among the identified cases retrieved from a private general practice. Cases involved five patients--one female and four males--ranging in age from 15 to 48 years. The authors concluded that LIAR appears to be a distinct but uncommon clinicopathologic condition that is self-limiting, and therefore warrants no definitive treatment. However, the condition, which can present asymptomatically on routine radiographs or is sometimes associated with clinical symptoms, warrants differentiation from periapical replacement resorption as a result of orthodontics or trauma. PMID:22479784

Kanas, Robert J; Kanas, Scott J

2012-03-01

259

External cervical resorption case report and a brief review of literature.  

Science.gov (United States)

External cervical resorption (ECR) is the loss of dental hard tissue as a result of odontoclastic action; it usually begins on the cervical region of the root surface of the teeth. The etiology, predisposing factors, diagnosis, and management of ECR have been reviewed here. Effective management and appropriate treatment can only be carried out if the true nature and exact location of the ECR lesion are known. This paper reports on the management of a case of external cervical root resorption (ECRR), which involved root canal treatment and removal of the resorbing area of the affected tooth as well as filling the resorbed area with mineral trioxide aggregate (MTA) and resin-modified glass ionomer filling material (RMGIC). The defect was filled with bone graft material and guided tissue regeneration (GTR) membrane. This case highlights the importance of using MTA and successful management of cervical resorption with a stable uneventful clinical recovery. PMID:24678232

Ahmed, Nizar; Gopalakrishnan; Mony, Bejoy; Parthasarthy, Harinath

2014-01-01

260

Inhibition of bone resorption in cultures of mouse calvariae by apicularen A.  

Science.gov (United States)

Apicularens A and B were isolated from the myxobacterial genus Chondromyces apiculatus JW184. Apicularen A inhibited bafilomycin A1-sensitive ATP-dependent proton transport into microsome vesicles more potently than apicularen B. Bone resorption in cultures of mouse calvariae induced by human parathyroid hormone (PTH) or interleukin-1beta (IL-1beta) was inhibited by apicularen A at 10 and 100 nM, while apicularen B had no effect. The bisphosphonate incadronate inhibited bone resorption at 100 nM, being less effective than apicularen A. Our findings indicate that apicularen A inhibits bone resorption induced by PTH or IL-1beta more potently than apicularen B, probably due to inhibition of the V-ATPase. PMID:17415879

Hong, JangJa; Sasaki, Hirokazu; Niikura, Kazuaki; Yanai, Maiko; Nakano, Yasuhiro; Yokomakura, Aya; Ishihara, Kenji; Hirasawa, Noriyasu; Kang, Young-Sook; Oh, Joa Sub; Kwak, Jong Hwan; Zee, OkPyo; Ohuchi, Kazuo

2007-02-01

 
 
 
 
261

Distribution of dissolved water in magmatic glass records growth and resorption of bubbles  

Science.gov (United States)

Volcanic eruptions are driven by the growth of gas bubbles in magma. Bubbles grow when dissolved volatile species, principally water, diffuse through the silicate melt and exsolve at the bubble wall. On rapid cooling, the melt quenches to glass, preserving the spatial distribution of water concentration around the bubbles (now vesicles), offering a window into pre-eruptive conditions. We measure the water distribution around vesicles in experimentally-vesiculated samples, with high spatial resolution. We find that, contrary to expectation, water concentration increases towards vesicles, indicating that water is resorbed from bubbles during cooling; textural evidence suggests that resorption occurs largely before the melt solidifies. Speciation data indicate that the molecular water distribution records resorption, whilst the hydroxyl distribution records earlier decompressive growth. Our results challenge the emerging paradigm that resorption indicates fluctuating pressure conditions, and lay the foundations for a new tool for reconstructing the eruptive history of natural volcanic products.

McIntosh, I. M.; Llewellin, E. W.; Humphreys, M. C. S.; Nichols, A. R. L.; Burgisser, A.; Schipper, C. I.; Larsen, J. F.

2014-09-01

262

Comparison between two tomographic sections in the diagnosis of external root resorption  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVES: To assess the accuracy of coronal and sagittal CT sections to detect cavities simulating root resorption. MATERIAL AND METHODS: 60 mandibular incisors were embedded in plaster bases, and cavities with 0.6, 1.2 or 1.8 mm in diameter and 0.3, 0.6 or 0.9 mm in depth (small, medium and large cavities were drilled on the buccal surfaces with high-speed round burs with diameters of 0.6, 1.2 and 1.8 mm to simulate external inflammatory root resorption. Simulations in the cervical, middle and apical thirds of each tooth root were made randomly. The Dental Scan software was used to obtain 1-mm-thick axial images from direct scanning, which were reconstructed in the coronal and sagittal planes using 3D software (Syngo FastView. Each series was loaded into the software. Fourteen images of each tooth were reconstructed in the coronal plane and 14 in the sagittal plane. A total of 1,652 images were obtained for analysis. Series information, tooth number and the plane reconstructed were stored. The images generated were saved on a CD-ROM together with the visualization software (Syngo FastView. Images were analyzed by a previously calibrated blinded, radiologist. Cochran's Q test was conducted separately for each region analyzed followed by pair-wise comparison by the McNemar test (p=0.05. RESULTS: No statistically significant difference (p>0.05 was observed in the diagnosis of simulated resorption between the apical, middle, and coronal thirds. When the axial plane was assessed separately, diagnoses were statistically different (p0.05 between planes, irrespective of the third in which the resorptions were located. CONCLUSION: When tomographic sections are requested for the diagnosis of buccal or lingual external root resorption, sagittal sections afford the best image characterization of the resorption process.

Cláudio Afonso Lermen

2010-06-01

263

Comparison between two tomographic sections in the diagnosis of external root resorption  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVES: To assess the accuracy of coronal and sagittal CT sections to detect cavities simulating root resorption. MATERIAL AND METHODS: 60 mandibular incisors were embedded in plaster bases, and cavities with 0.6, 1.2 or 1.8 mm in diameter and 0.3, 0.6 or 0.9 mm in depth (small, medium and large [...] cavities) were drilled on the buccal surfaces with high-speed round burs with diameters of 0.6, 1.2 and 1.8 mm to simulate external inflammatory root resorption. Simulations in the cervical, middle and apical thirds of each tooth root were made randomly. The Dental Scan software was used to obtain 1-mm-thick axial images from direct scanning, which were reconstructed in the coronal and sagittal planes using 3D software (Syngo FastView). Each series was loaded into the software. Fourteen images of each tooth were reconstructed in the coronal plane and 14 in the sagittal plane. A total of 1,652 images were obtained for analysis. Series information, tooth number and the plane reconstructed were stored. The images generated were saved on a CD-ROM together with the visualization software (Syngo FastView). Images were analyzed by a previously calibrated blinded, radiologist. Cochran's Q test was conducted separately for each region analyzed followed by pair-wise comparison by the McNemar test (p=0.05). RESULTS: No statistically significant difference (p>0.05) was observed in the diagnosis of simulated resorption between the apical, middle, and coronal thirds. When the axial plane was assessed separately, diagnoses were statistically different (p0.05) between planes, irrespective of the third in which the resorptions were located. CONCLUSION: When tomographic sections are requested for the diagnosis of buccal or lingual external root resorption, sagittal sections afford the best image characterization of the resorption process.

Cláudio Afonso, Lermen; Gabriela Salatino, Liedke; Heloísa Emília Dias da, Silveira; Heraldo Luis Dias da, Silveira; Alessandro André, Mazzola; José Antônio Poli de, Figueiredo.

2010-06-01

264

Comparison between two tomographic sections in the diagnosis of external root resorption  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVES: To assess the accuracy of coronal and sagittal CT sections to detect cavities simulating root resorption. MATERIAL AND METHODS: 60 mandibular incisors were embedded in plaster bases, and cavities with 0.6, 1.2 or 1.8 mm in diameter and 0.3, 0.6 or 0.9 mm in depth (small, medium and large [...] cavities) were drilled on the buccal surfaces with high-speed round burs with diameters of 0.6, 1.2 and 1.8 mm to simulate external inflammatory root resorption. Simulations in the cervical, middle and apical thirds of each tooth root were made randomly. The Dental Scan software was used to obtain 1-mm-thick axial images from direct scanning, which were reconstructed in the coronal and sagittal planes using 3D software (Syngo FastView). Each series was loaded into the software. Fourteen images of each tooth were reconstructed in the coronal plane and 14 in the sagittal plane. A total of 1,652 images were obtained for analysis. Series information, tooth number and the plane reconstructed were stored. The images generated were saved on a CD-ROM together with the visualization software (Syngo FastView). Images were analyzed by a previously calibrated blinded, radiologist. Cochran's Q test was conducted separately for each region analyzed followed by pair-wise comparison by the McNemar test (p=0.05). RESULTS: No statistically significant difference (p>0.05) was observed in the diagnosis of simulated resorption between the apical, middle, and coronal thirds. When the axial plane was assessed separately, diagnoses were statistically different (p0.05) between planes, irrespective of the third in which the resorptions were located. CONCLUSION: When tomographic sections are requested for the diagnosis of buccal or lingual external root resorption, sagittal sections afford the best image characterization of the resorption process.

Cláudio Afonso, Lermen; Gabriela Salatino, Liedke; Heloísa Emília Dias da, Silveira; Heraldo Luis Dias da, Silveira; Alessandro André, Mazzola; José Antônio Poli de, Figueiredo.

265

AMBIENT PARTICULATE MATTER DECREASED IN HUMAN ALVEOLAR MACHROPHAGE CYTOKINE RELEASE  

Science.gov (United States)

Human exposure to ambient airborne particulate matter (PM) is associated with cardiopulmonary mortality and morbidity, including increased hospitalizations for lung infection. Normal lung immune responses to bacterial infection include alveolar macrophage cytokine production and...

266

*Ambient Particluate Matter Supresses Alveolar Macrophage Cytokine Response to Lipopolysaccharide  

Science.gov (United States)

Reports link ambient particulate matter (PM) exposure with cardiopulmonary mortality and morbidity, including the exacerbation of inflammatory disease and increased hospitalization for lung infections. Alveolar macrophages (AM) play an important defense role against infections v...

267

Inferior alveolar nerve sensitivity changes after mandibular trauma  

Directory of Open Access Journals (Sweden)

Full Text Available The investigation was performed on 195 patients, who had fracture on mandibular angle zone. In control group pain thresholds of infraorbital nerve and inferior alveolar nerve did not differ significantly (p > 0.05. Consequently, lesion degree of inferior alveolar nerve and its functional recovery dynamics were estimated objectively according to pain threshold and lesion index of neural function. Stump dislocation extent has influence on neural lesion: the more expressed dislocation, the higher likelihood of severe lesion of inferior alveolar nerve. Three degrees of neural lesion were identified in the case of mandibular angle fracture. When minor lesion of inferior alveolar nerve took place (17.4%, sensation recovered in 21 days after stump reposition and fixation; moderate lesion of nerve (55.8% had sensory recovery after 28 days, and in the case of severe lesion of nerve (26.6% neural function did not recover even after 90 days.

Simonas Grybauskas

2010-12-01

268

Comparison between two tomographic sections in the diagnosis of external root resorption  

Digital Repository Infrastructure Vision for European Research (DRIVER)

OBJECTIVES: To assess the accuracy of coronal and sagittal CT sections to detect cavities simulating root resorption. MATERIAL AND METHODS: 60 mandibular incisors were embedded in plaster bases, and cavities with 0.6, 1.2 or 1.8 mm in diameter and 0.3, 0.6 or 0.9 mm in depth (small, medium and large cavities) were drilled on the buccal surfaces with high-speed round burs with diameters of 0.6, 1.2 and 1.8 mm to simulate external inflammatory root resorption. Simulations in the cervical, middl...

Cláudio Afonso Lermen; Gabriela Salatino Liedke; Heloísa Emília Dias da Silveira; Heraldo Luis Dias da Silveira; Alessandro André Mazzola; José Antônio Poli De Figueiredo

2010-01-01

269

Dissolved water distribution in vesicular magmatic glass records both decompressive bubble growth and quench resorption  

Science.gov (United States)

Water distribution in magma varies over the lifetime of an eruption due to a variety of processes, including decompressive degassing of the melt, cooling during the quench from melt to glass, and post-emplacement hydration under ambient conditions. Correct interpretation of water distributions in erupted pyroclasts can therefore offer crucial insights into the dynamics of eruption mechanisms and emplacement histories. Volcanic eruptions are driven by the nucleation and growth of bubbles in magma. Bubbles grow as volatile species in the melt, of which water is volumetrically the most important, diffuse down a concentration gradient towards and across the bubble wall. On cooling, the melt quenches to glass, preserving the spatial distribution of water concentration around the bubbles (now vesicles). We use Backscatter Scanning Electron Microscopy (BSEM), Secondary Ion Mass Spectrometry (SIMS) and Fourier Transform Infra-Red spectroscopy (FTIR) to measure the spatial distribution of water around vesicles in experimentally-vesiculated samples. We find that, contrary to expectation, the total water concentration increases (by up to 2 wt.%) in the ~30 microns closest to the vesicle wall. Our samples record significant resorption of water back into the melt around bubbles during the quench process, a process which represents ';regassing' of the magma. We propose that the observed total water resorption profiles result from the increase in the equilibrium solubility of water as temperature decreases during the quench to glass, and that this resorption locally overprints the pre-existing concentration total water profile resulting from bubble growth during decompression. This resorption occurs over the very short timescales of rapid experimental quench (3-10 seconds) resulting in strongly disequilibrium water speciation. Water re-enters the melt as molecular water leading to enrichment in molecular water around vesicles, while the distribution of hydroxyl groups remains relatively unaltered during quench, thus preserving information about syn-experimental (or syn-eruptive) degassing. Our work demonstrates the effectiveness of two tools for deciphering the water contents of pyroclasts. BSEM imaging of glassy pyroclasts offers an easy, qualitative assessment of whether glass has been affected by quench resorption or secondary alteration processes, which becomes quantitative if calibrated by a technique such as SIMS. FTIR speciation data, meanwhile, enables the cause of bubble resorption to be identified, since resorption caused by pressure increase and by temperature decrease will result in distinctly different distributions of water species. We present here data extracted using these tools that demonstrate the potential impact of temperature-controlled quench resorption, which can reduce bubble volumes and sample porosities by a factor of two and reintroduce significant amounts of water back into the melt, with implications for obsidian and rheomorphic flow mechanisms.

McIntosh, I. M.; Llewellin, E.; Humphreys, M.; Nichols, A. R.; Burgisser, A.; Schipper, C.

2013-12-01

270

Hypoxia-inducible factors promote alveolar development and regeneration.  

Science.gov (United States)

Understanding how alveoli and the underlying capillary network develop and how these mechanisms are disrupted in disease states is critical for developing effective therapies for lung regeneration. Recent evidence suggests that lung angiogenesis promotes lung development and repair. Vascular endothelial growth factor (VEGF) preserves lung angiogenesis and alveolarization in experimental O2-induced arrested alveolar growth in newborn rats, but combined VEGF+angiopoietin 1 treatment is necessary to correct VEGF-induced vessel leakiness. Hypoxia-inducible factors (HIFs) are transcription factors that activate multiple O2-sensitive genes, including those encoding for angiogenic growth factors, but their role during postnatal lung growth is incompletely understood. By inducing the expression of a range of angiogenic factors in a coordinated fashion, HIF may orchestrate efficient and safe angiogenesis superior to VEGF. We hypothesized that HIF inhibition impairs alveolarization and that HIF activation regenerates irreversible O2-induced arrested alveolar growth. HIF inhibition by intratracheal dominant-negative adenovirus (dnHIF-1?)-mediated gene transfer or chetomin decreased lung HIF-1?, HIF-2?, and VEGF expression and led to air space enlargement and arrested lung vascular growth. In experimental O2-induced arrested alveolar growth in newborn rats, the characteristic features of air space enlargement and loss of lung capillaries were associated with decreased lung HIF-1? and HIF-2? expression. Intratracheal administration of Ad.HIF-1? restored HIF-1?, endothelial nitric oxide synthase, VEGF, VEGFR2, and Tie2 expression and preserved and rescued alveolar growth and lung capillary formation in this model. HIFs promote normal alveolar development and may be useful targets for alveolar regeneration. PMID:23962064

Vadivel, Arul; Alphonse, Rajesh S; Etches, Nicholas; van Haaften, Timothy; Collins, Jennifer J P; O'Reilly, Megan; Eaton, Farah; Thébaud, Bernard

2014-01-01

271

Alveolar lymphangioma in infants: report of two cases.  

LENUS (Irish Health Repository)

The alveolar lymphangioma is a benign but relatively rare condition found only in the oral cavities of black infants. Dentists practising in Ireland may be unaware of this condition due to its racial specificity. This paper presents two case reports of multiple alveolar lymphangiomas found in black infants in a children\\'s hospital in Ireland. The epidemiology, aetiology, clinical presentation, histology, and management options are discussed. The photographs should aid the practitioner in recognising these lesions.

FitzGerald, Kirsten

2012-02-01

272

Alveolar lymphangioma in infants: report of two cases.  

LENUS (Irish Health Repository)

The alveolar lymphangioma is a benign but relatively rare condition found only in the oral cavities of black infants. Dentists practising in Ireland may be unaware of this condition due to its racial specificity. This paper presents two case reports of multiple alveolar lymphangiomas found in black infants in a children\\'s hospital in Ireland. The epidemiology, aetiology, clinical presentation, histology, and management options are discussed. The photographs should aid the practitioner in recognising these lesions.

FitzGerald, Kirsten

2009-06-01

273

Diffuse alveolar hemorrhage in Wegener?s granulomatosis  

Directory of Open Access Journals (Sweden)

Full Text Available Diffuse alveolar hemorrhage is a life-threatening though rare manifestation of Wegener?s granulomatosis (WG. An active diagnostic workup, intensive observation, and aggressive immunosuppressive treatment are cornerstones of the management. The treatment modalities available for such complications are pulse cyclophosphamide therapy with steroids. We report here a case of WG with diffuse alveolar hemorrhage as the first manifestation of the disease in life that responded to steroids and cyclophosphamide.

Mahajan Vineet

2011-01-01

274

Hydrogen ion currents in rat alveolar epithelial cells.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Alveolar epithelial cells isolated from rats and maintained in primary culture were studied using the whole-cell configuration of the "patch-clamp" technique. After other ionic conductances were eliminated by replacing permeant ions with N-methyl-D-glucamine methanesulfonate, large voltage-activated hydrogen-selective currents were observed. Like H+ currents in snail neurons and axolotl oocytes, those in alveolar epithelium are activated by depolarization, deactivate upon repolarization, and ...

Decoursey, T. E.

1991-01-01

275

Anaesthetic management of bilateral alveolar proteinosis for bronchopulmonary lavage.  

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Full Text Available The most hazardous manifestation of pulmonary alveolar proteinosis is progressive hypoxia for which bronchopulmonary lavage (BPL is the single most effective treatment. Unfortunately this procedure under general anesthesia itself increases the risk of hypoxia due to the need for one lung ventilation. It was therefore considered interesting to report the successful anaesthetic management of a patient with pulmonary alveolar proteinosis for Bronchopulmonary lavage.

Dixit R

1998-01-01

276

Influence of ridge type on mandibular distal extension removable partial denture.  

Science.gov (United States)

The aim of this study was to use photoelastic models to analyze the distribution of stress caused by the incidence of loads on a mandibular distal extension removable partial denture, both on the abutment teeth and on differently shaped residual ridges: distal ascending, descending-ascending, horizontal and distal descending. The best type of retainer and location of the rest on the last abutment tooth were determined for the different types of ridge. Four models were made from photoelastic resin (PL-1 for the teeth and PL-2 for the alveolar ridge), one for each kind of ridge. For each model, 4 removable partial dentures (RPD) were made (16 RPD altogether): T-bar retainer and distal rest, T-bar retainer and mesial rest, circumferential retainer and distal rest, and circumferential retainer and mesial rest. The models were placed on a circular polariscope and a 100 N axial load (point load) was applied to premolars and molars of the RPD. The formation of photoelastic bands was photographed for qualitative analysis. Results showed that the horizontal ridge had better distribution of stress, while the distal descending ridge had greater concentration of stress. The circumferential retainer had greater areas of stress for all types of ridges except the horizontal ridge, where there was no influence related to retainer type. The distribution of stress was similar among the different types of ridges when the rest was mesial or distal to the last abutment tooth, except for the distal descending ridge, where there was greater concentration of stress when the rest was located distally to the last abutment tooth. Thus, it may be concluded that (1) the situation was least favorable for the distal descending ridge and most favorable for the horizontal ridge, (2) the T-bar retainer had more favorable stress distribution, except when the ridge was horizontal, in which case there was no influence in relation to the type of retainer, (3) the location of the rest showed similar behavior in all except the distal descending ridge. PMID:20645647

Pellizzer, Eduardo Piza; Ferraço, Renato; Tonella, Bianca Piccolotto; Oliveira, Bruno J de Cazaes; Souza, Fabiano Lopes; Falcón-Antenucci, Rosse M

2010-01-01

277

Pulmonary surfactant surface tension influences alveolar capillary shape and oxygenation.  

Science.gov (United States)

Alveolar capillaries are located in close proximity to the alveolar epithelium and beneath the surfactant film. We hypothesized that the shape of alveolar capillaries and accompanying oxygenation are influenced by surfactant surface tension in the alveolus. To prove our hypothesis, surfactant surface tension was regulated by conditional expression of surfactant protein (SP)-B in Sftpb(-/-) mice, thereby inhibiting surface tension-lowering properties of surfactant in vivo within 24 hours after depletion of Sftpb. Minimum surface tension of isolated surfactant was increased and oxygen saturation was significantly reduced after 2 days of SP-B deficiency in association with deformation of alveolar capillaries. Intravascularly injected 3.2-mum-diameter microbeads through jugular vein were retained within narrowed pulmonary capillaries after reduction of SP-B. Ultrastructure studies demonstrated that the capillary protrusion typical of the normal alveolar-capillary unit was reduced in size, consistent with altered pulmonary blood flow. Pulmonary hypertension and intrapulmonary shunting are commonly associated with surfactant deficiency and dysfunction in neonates and adults with respiratory distress syndromes. Increased surfactant surface tension caused by reduction in SP-B induced narrowing of alveolar capillaries and oxygen desaturation, demonstrating an important role of surface tension-lowering properties of surfactant in the regulation of pulmonary vascular perfusion. PMID:19202005

Ikegami, Machiko; Weaver, Timothy E; Grant, Shawn N; Whitsett, Jeffrey A

2009-10-01

278

Horizontal alveolar bone loss: A periodontal orphan  

Directory of Open Access Journals (Sweden)

Full Text Available Background: Attempts to successfully regenerate lost alveolar bone have always been a clinician?s dream. Angular defects, at least, have a fairer chance, but the same cannot be said about horizontal bone loss. The purpose of the present study was to evaluate the prevalence of horizontal alveolar bone loss and vertical bone defects in periodontal patients; and later, to correlate it with the treatment modalities available in the literature for horizontal and vertical bone defects. Materials and Methods: The study was conducted in two parts. Part I was the radiographic evaluation of 150 orthopantomographs (OPGs (of patients diagnosed with chronic periodontitis and seeking periodontal care, which were digitized and read using the AutoCAD 2006 software. All the periodontitis-affected teeth were categorized as teeth with vertical defects (if the defect angle was ?45° and defect depth was ?3 mm or as having horizontal bone loss. Part II of the study comprised search of the literature on treatment modalities for horizontal and vertical bone loss in four selected periodontal journals. Results: Out of the 150 OPGs studied, 54 (36% OPGs showed one or more vertical defects. Totally, 3,371 teeth were studied, out of which horizontal bone loss was found in 3,107 (92.2% teeth, and vertical defects were found only in 264 (7.8% of the teeth, which was statistically significant (P<.001. Search of the selected journals revealed 477 papers have addressed the treatment modalities for vertical and horizontal types of bone loss specifically. Out of the 477 papers, 461 (96.3% have addressed vertical bone loss, and 18 (3.7% have addressed treatment options for horizontal bone loss. Two papers have addressed both types of bone loss and are included in both categories. Conclusion: Horizontal bone loss is more prevalent than vertical bone loss but has been sidelined by researchers as very few papers have been published on the subject of regenerative treatment modalities for this type of bone loss. This study should be an impetus for greater attention to an otherwise ubiquitous periodontal challenge.

Jayakumar A

2010-01-01

279

Reduction of mandibular residual ridge after vestibuloplasty. A two-year follow-up study comparing the Edlan flap, mucosal and skin graft operations  

DEFF Research Database (Denmark)

Mandibular residual ridge reduction (RRR) after Edlan flap vestibuloplasty, buccal mucosal graft, and split skin graft vestibuloplasty was measured on lateral cephalometric radiographs obtained 1, 3, 6, 12 and 24 months postsurgery in 50 patients. The ridge reduction was most severe during the immediate postoperative period. The different operation methods did not give rise to significant variations in the reduction pattern, neither did the sex of the patient appear to be an important factor. The temporary increase of mandibular resorption after vestibuloplasty surgery is of a magnitude comparable to the average RRR during 1 year in full denture wearers with a long denture experience.

Hillerup, SØren; Eriksen, Erik

1989-01-01

280

Bayesian inference of the lung alveolar spatial model for the identification of alveolar mechanics associated with acute respiratory distress syndrome  

Science.gov (United States)

Acute respiratory distress syndrome (ARDS) is acute lung failure secondary to severe systemic inflammation, resulting in a derangement of alveolar mechanics (i.e. the dynamic change in alveolar size and shape during tidal ventilation), leading to alveolar instability that can cause further damage to the pulmonary parenchyma. Mechanical ventilation is a mainstay in the treatment of ARDS, but may induce mechano-physical stresses on unstable alveoli, which can paradoxically propagate the cellular and molecular processes exacerbating ARDS pathology. This phenomenon is called ventilator induced lung injury (VILI), and plays a significant role in morbidity and mortality associated with ARDS. In order to identify optimal ventilation strategies to limit VILI and treat ARDS, it is necessary to understand the complex interplay between biological and physical mechanisms of VILI, first at the alveolar level, and then in aggregate at the whole-lung level. Since there is no current consensus about the underlying dynamics of alveolar mechanics, as an initial step we investigate the ventilatory dynamics of an alveolar sac (AS) with the lung alveolar spatial model (LASM), a 3D spatial biomechanical representation of the AS and its interaction with airflow pressure and the surface tension effects of pulmonary surfactant. We use the LASM to identify the mechanical ramifications of alveolar dynamics associated with ARDS. Using graphical processing unit parallel algorithms, we perform Bayesian inference on the model parameters using experimental data from rat lung under control and Tween-induced ARDS conditions. Our results provide two plausible models that recapitulate two fundamental hypotheses about volume change at the alveolar level: (1) increase in alveolar size through isotropic volume change, or (2) minimal change in AS radius with primary expansion of the mouth of the AS, with the implication that the majority of change in lung volume during the respiratory cycle occurs in the alveolar ducts. These two model solutions correspond to significantly different mechanical properties of the tissue, and we discuss the implications of these different properties and the requirements for new experimental data to discriminate between the hypotheses.

Christley, Scott; Emr, Bryanna; Ghosh, Auyon; Satalin, Josh; Gatto, Louis; Vodovotz, Yoram; Nieman, Gary F.; An, Gary

2013-06-01

 
 
 
 
281

Bayesian inference of the lung alveolar spatial model for the identification of alveolar mechanics associated with acute respiratory distress syndrome  

International Nuclear Information System (INIS)

Acute respiratory distress syndrome (ARDS) is acute lung failure secondary to severe systemic inflammation, resulting in a derangement of alveolar mechanics (i.e. the dynamic change in alveolar size and shape during tidal ventilation), leading to alveolar instability that can cause further damage to the pulmonary parenchyma. Mechanical ventilation is a mainstay in the treatment of ARDS, but may induce mechano-physical stresses on unstable alveoli, which can paradoxically propagate the cellular and molecular processes exacerbating ARDS pathology. This phenomenon is called ventilator induced lung injury (VILI), and plays a significant role in morbidity and mortality associated with ARDS. In order to identify optimal ventilation strategies to limit VILI and treat ARDS, it is necessary to understand the complex interplay between biological and physical mechanisms of VILI, first at the alveolar level, and then in aggregate at the whole-lung level. Since there is no current consensus about the underlying dynamics of alveolar mechanics, as an initial step we investigate the ventilatory dynamics of an alveolar sac (AS) with the lung alveolar spatial model (LASM), a 3D spatial biomechanical representation of the AS and its interaction with airflow pressure and the surface tension effects of pulmonary surfactant. We use the LASM to identify the mechanical ramifications of alveolar dynamics associated with ARDS. Using graphical processing unit parallel algorithms, we perform Bayg unit parallel algorithms, we perform Bayesian inference on the model parameters using experimental data from rat lung under control and Tween-induced ARDS conditions. Our results provide two plausible models that recapitulate two fundamental hypotheses about volume change at the alveolar level: (1) increase in alveolar size through isotropic volume change, or (2) minimal change in AS radius with primary expansion of the mouth of the AS, with the implication that the majority of change in lung volume during the respiratory cycle occurs in the alveolar ducts. These two model solutions correspond to significantly different mechanical properties of the tissue, and we discuss the implications of these different properties and the requirements for new experimental data to discriminate between the hypotheses. (paper)

282

Screening of protein kinase inhibitors identifies PKC inhibitors as inhibitors of osteoclastic acid secretion and bone resorption  

DEFF Research Database (Denmark)

Bone resorption is initiated by osteoclastic acidification of the resorption lacunae. This process is mediated by secretion of protons through the V-ATPase and chloride through the chloride antiporter ClC-7. To shed light on the intracellular signalling controlling extracellular acidification, we screened a protein kinase inhibitor library in human osteoclasts.

SØrensen, Mette G; Karsdal, Morten A

2010-01-01

283

Antithetic effects of ryanodine and ruthenium red on osteoclast-mediated bone resorption and intracellular calcium concentrations.  

Science.gov (United States)

In the process of bone remodeling, osteoclasts are responsible for resorption of bone. High levels of intracellular calcium decrease the bone resorbing activity of osteoclasts and increase detachment of osteoclasts from the bone surface. The regulatory role of intracellular calcium in bone resorption is not clearly understood. To understand this phenomenon, we studied the effects of the intracellular calcium modulators ryanodine and ruthenium red on bone resorption using the disaggregated osteoclast pit assay. Changes in intracellular calcium concentrations after treatment with these compounds were detected with the fluoroprobe fura2. With ryanodine, a significant, dose-dependent decrease in bone resorption was detected. This inhibition of bone resorption was reversible upon the removal of ryanodine. Ryanodine increased intracellular calcium concentrations, suggesting that the mechanism of inhibition by ryanodine was via alterations in intracellular stores of calcium. After treatment with ruthenium red, osteoclasts resorbed significantly more bone compared to vehicle-treated cells. This increase in bone resorption correlated with a decrease in intracellular calcium concentrations. The addition of parathyroid hormone or ruthenium red to osteoclast cultures containing ryanodine did not attenuate the decrease in bone resorption caused by ryanodine, suggesting that the mechanism of ryanodine inhibition of bone resorption may involve the "locking" of a calcium channel in an open position. PMID:8904321

Ritchie, C K; Strei, T A; Maercklein, P B; Fitzpatrick, L A

1995-10-01

284

The angiogenic factor midkine is regulated by dexamethasone and retinoic acid during alveolarization and in alveolar epithelial cells  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background A precise balance exists between the actions of endogenous glucocorticoids (GC and retinoids to promote normal lung development, in particular during alveolarization. The mechanisms controlling this balance are largely unknown, but recent evidence suggests that midkine (MK, a retinoic acid-regulated, pro-angiogenic growth factor, may function as a critical regulator. The purpose of this study was to examine regulation of MK by GC and RA during postnatal alveolar formation in rats. Methods Newborn rats were treated with dexamethasone (DEX and/or all-trans-retinoic acid (RA during the first two weeks of life. Lung morphology was assessed by light microscopy and radial alveolar counts. MK mRNA and protein expression in response to different treatment were determined by Northern and Western blots. In addition, MK protein expression in cultured human alveolar type 2-like cells treated with DEX and RA was also determined. Results Lung histology confirmed that DEX treatment inhibited and RA treatment stimulated alveolar formation, whereas concurrent administration of RA with DEX prevented the DEX effects. During normal development, MK expression was maximal during the period of alveolarization from postnatal day 5 (PN5 to PN15. DEX treatment of rat pups decreased, and RA treatment increased lung MK expression, whereas concurrent DEX+RA treatment prevented the DEX-induced decrease in MK expression. Using human alveolar type 2 (AT2-like cells differentiated in culture, we confirmed that DEX and cAMP decreased, and RA increased MK expression. Conclusion We conclude that MK is expressed by AT2 cells, and is differentially regulated by corticosteroid and retinoid treatment in a manner consistent with hormonal effects on alveolarization during postnatal lung development.

Sweezey Neil B

2009-08-01

285

Assessment of different markers of bone resorption in postmenopausal osteoporotic women treated with pamidronate.  

Science.gov (United States)

The aim of this study was to evaluate the different bone resorption markers, total pyridinoline (Pyr) and total deoxypyridinoline (Dpyr), assessed by a HPLC method, free Dpyr, assessed by a new immunoassay, and urinary excretion of hydroxyproline (OH-proline), in postmenopausal osteoporotic women during long-term treatment with pamidronate. A total of 60 postmenopausal women with previous distal forearm fracture were included in this 12-month placebo-controlled and double-blind study, where intermittent oral pamidronate, 75 or 150 mg, or placebo were given daily for 4 weeks, every 16 weeks. After 1 week a significant reduction in urinary excretion of total Dpyr was observed in the group treated with 150 mg pamidronate compared to the placebo (p Pyrilinks-D assay) at baseline was r = 0.91. Total Dpyr assessed by the HPLC method reflects the pamidronate-induced decrease in bone resorption, and the changes in this resorption marker were more pronounced than changes in free Dpyr, total Pyr and OH-proline. In this study free Dpyr analysis was less suitable for reflecting bone resorption during bisphosphonate therapy. PMID:9350066

Kollerup, G; Sørensen, H A; Hyldstrup, L; Storm, T

1997-10-01

286

Characteristics of trabecular bone resorption cavities in patients with chronic renal failure.  

Science.gov (United States)

Using a computerised technique, resorption cavity characteristics in iliac crest trabecular bone were assessed in 30 patients with chronic renal failure and compared with data obtained from healthy subjects. The mean and maximum cavity depth were significantly greater in the patient group (P less than 0.0001); in addition, cavity area, the percentage of bone being remodelled, the number of cavities per mm trabecular surface and the percentage eroded surface were all significantly greater than in controls (P less than 0.0001). However, the surface length of individual cavities in the patient group did not differ significantly from that of controls. In the patient group, serum intact parathyroid hormone concentrations showed a significant positive correlation with mean resorption cavity depth (r = 0.451, P less than 0.05). Our results demonstrate that the increase in bone resorption associated with hyperparathyroidism secondary to chronic renal failure is due to an increase both in the number and depth of cavities, although the surface extent of individual cavities is normal. These findings indicate that factors determining the length of trabecular surface eroded and the depth of individual resorption cavities are controlled by different mechanisms. PMID:1576489

Croucher, P I; Wright, C D; Garrahan, N J; Kudlac, H; Williams, A J; Compston, J E

1992-02-01

287

On the assessment of radionuclide resorption from the gastro-intestinal tract of the blood  

International Nuclear Information System (INIS)

A comparison of the resorption rates measured for the radionuclides Ce, Co, Pu, Ru, Sr and Zn as well as the vitamin B12 with the recommendations for calculation given by the SSK showed that the values used by the SSK partly are too low by orders of magnitude. The dose factors therefore no longer correspond to the international level of science. (DG)

288

Immunohistochemical expression of biglycan and decorin in the pulp tissue of human primary teeth during resorption  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Primary teeth are interesting models that can be used to study physiological and pathological processes involving cells and extracellular matrices in hard and soft tissues. This study investigated the expression and distribution of biglycan and decorin-the non-collagenous components of the extracell [...] ular matrix-in primary teeth tissue, during physiological root resorption. Thirty healthy human primary teeth were grouped together according to root length: Group I - two-thirds root length, Group II - one-third root length, and Group III - teeth with no root. The streptavidin-biotin-peroxidase immunohistochemical method was used with antibodies against the previously named antigens. The proteoglycans studied were found in the pulp and dentin extracellular matrix in all groups without any differences in the proteins, among the groups. Biglycan was observed mainly in predentin and in pulp connective tissue in the resorption area. In addition, decorin was observed mainly in pulp connective tissue, but near the resorption area. Biglycan and decorin were distributed differentially in the dental tissues. The present immunohistocytochemical data, combined with previously reported data, suggest that these proteoglycans could be involved in regulating the physiological resorption process in healthy primary teeth.

Monique Saveriano De, Benedetto; Filipe Modolo, Siqueira; Marcelo Betti, Mascaro; Vera Cavalcanti, Araujo; Marcelo Jose Strazzeri, Bonecker.

289

Glucocorticoid-Induced Changes in the Geometry of Osteoclast Resorption Cavities Affect Trabecular Bone Stiffness  

DEFF Research Database (Denmark)

Bone fracture risk can increase through bone microstructural changes observed in bone pathologies, such as glucocorticoid-induced osteoporosis. Resorption cavities present one of these microstructural aspects. We recently found that glucocorticoids (GCs) affect the shape of the resorption cavities. Specifically, we found that in the presence of GC osteoclasts (OCs) cultured on bone slices make more trenchlike cavities, compared to rather round cavities in the absence of GCs, while the total eroded surface remained constant. For this study, we hypothesized that trenchlike cavities affect bone strength differently compared to round cavities. To test this hypothesis, we cultured OCs on bone slices in the presence and absence of GC and quantified their dimensions. These data were used to model the effects of OC resorption cavities on bone mechanical properties using a validated beam-shell finite element model of trabecular bone. We demonstrated that a change in the geometry of resorption cavities is sufficient toaffect bone competence. After correcting for the increased EV/BV with GCs, the difference to the control condition was no longer significant, indicating that the GC-induced increase in EV/BV, which is closely related to the shape of the cavities, highly determines the stiffness effect. The lumbar spine was the anatomic site most affected by the GC-induced changes on the shape of the cavities. These findings might explain the clinical observation that the prevalence of vertebral fractures during GC treatment increases more than hip, forearm and other nonvertebral fractures.

Vanderoost, Jef; SØe, Kent

2012-01-01

290

Immunohistochemical expression of biglycan and decorin in the pulp tissue of human primary teeth during resorption  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Primary teeth are interesting models that can be used to study physiological and pathological processes involving cells and extracellular matrices in hard and soft tissues. This study investigated the expression and distribution of biglycan and decorin-the non-collagenous components of the extracell [...] ular matrix-in primary teeth tissue, during physiological root resorption. Thirty healthy human primary teeth were grouped together according to root length: Group I - two-thirds root length, Group II - one-third root length, and Group III - teeth with no root. The streptavidin-biotin-peroxidase immunohistochemical method was used with antibodies against the previously named antigens. The proteoglycans studied were found in the pulp and dentin extracellular matrix in all groups without any differences in the proteins, among the groups. Biglycan was observed mainly in predentin and in pulp connective tissue in the resorption area. In addition, decorin was observed mainly in pulp connective tissue, but near the resorption area. Biglycan and decorin were distributed differentially in the dental tissues. The present immunohistocytochemical data, combined with previously reported data, suggest that these proteoglycans could be involved in regulating the physiological resorption process in healthy primary teeth.

Monique Saveriano De, Benedetto; Filipe Modolo, Siqueira; Marcelo Betti, Mascaro; Vera Cavalcanti, Araujo; Marcelo Jose Strazzeri, Bonecker.

2013-09-01

291

Identifying enamel diffusion properties in feline teeth affected with resorptive lesions  

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Full Text Available Various factors have been suggested in the pathogenesis of feline resorptive lesions, such as periodontal disease, dietary factors, mechanical stress, developmental tooth defects, breed and viral disease, although none of these factors have been definitively proven to be the direct cause. It was recently published that normally enamel in cats is significantly thinner at the cemento-enamel junction, and both enamel and dentine are significantly less mineralized than elsewhere on the tooth. However, it is still unclear what anatomical features of the tooth surface are associated with a predisposition for resorptive lesions, and what is the initiating cause for the clastic activity afterwards. The present study was undertaken with the aim to describe enamel properties of transport and distribution of organic molecules in intact feline teeth and teeth affected with resorptive lesions. The results indicate that damaged enamel is prone to a greater bilateral diffusion process, leading to continuous disruption of the enamel structure. Also, teeth that are subjected to occlusal stress are at greater risk of destruction because micro fractures produce disarrangements in feline dental tissue diffusion homeostasis. The relationship between these features with feline dental resorptive lesions requires further studies.

Živkovi? R.

2011-01-01

292

Inhibition of osteoclast bone resorption activity through osteoprotegerin-induced damage of the sealing zone.  

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Bone remodeling is dependent on the dynamic equilibrium between osteoclast-mediated bone resorption and osteoblast-mediated osteogenesis. The sealing zone is an osteoclast-specific cytoskeletal structure, the integrity of which is critical for osteoclast-mediated bone resorption. To date, studies have focused mainly on the osteoprotegerin (OPG)?induced inhibition of osteoclast differentiation through the OPG/receptor activator of the nuclear factor kappa-B ligand (RANKL)/RANK system, which affects the bone resorption of osteoclasts. However, the effects of OPG on the sealing zone have not been reported to date. In this study, the formation of the sealing zone was observed by Hoffman modulation contrast (HMC) microscopy and confocal laser scanning microscopy. The effects of OPG on the existing sealing zone and osteoclast-mediated bone resorption activity, as well as the regulatory role of genes involved in the formation of the sealing zone were examined by immunofluorescence staining, HMC microscopy, quantitative reverse transcription polymerase chain reaction (RT-qPCR), western blot analysis and scanning electron microscopy. The sealing zone was formed on day 5, with belt-like protuberances at the cell edge and scattered distribution of cell nuclei, but no filopodia. The sealing zone was intact in the untreated control group. However, defects in the sealing zone were observed in the OPG-treated group (20 ng/ml) and the structure was absent in the groups treated with 40 and 80 ng/ml OPG. The podosomes showed a scattered or clustered distribution between the basal surface of the osteoclasts and the well surface. Furthermore, resorption lacunae were not detected in the 20 ng/ml OPG-treated group, indicating the loss of osteoclast-mediated bone resorption activity. Treatment with OPG resulted in a significant decrease in the expression of Arhgef8/Net1 and DOCK5 Rho guanine nucleotide exchange factors (RhoGEFs), 10 of 18 RhoGTPases (RhoA, RhoB, cdc42v1, cdc42v2, RhoU/Wrch1, RhoF/Rif, Rac2, RhoG, Rnd1 and RhoBTB1), ROCK1 and ROCK2. In conclusion, podosome distribution was affected by the OPG-induced inhibition of the expression of genes in the RhoGTPase signaling pathway. This resulted in damage to or destruction of the sealing zone, thus inhibiting osteoclast-mediated bone resorption activity. PMID:25017214

Song, Ruilong; Gu, Jianhong; Liu, Xuezhong; Zhu, Jiaqiao; Wang, Qichao; Gao, Qian; Zhang, Jiaming; Cheng, Laiyang; Tong, Xishuai; Qi, Xinyi; Yuan, Yan; Liu, Zongping

2014-09-01

293

Asymmetric ( UC)albumin transport across bullfrog alveolar epithelium  

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Bullfrog lungs were prepared as planar sheets and bathed with Ringer solution in Ussing chambers. In the presence of a constant electrical gradient (20, 0, or -20 mV) across the tissue, UC-labeled bovine serum albumin or inulin was instilled into the upstream reservoir and the rate of appearance of the tracer in the downstream reservoir was monitored. Two lungs from the same animal were used to determine any directional difference in tracer fluxes. An apparent permeability coefficient was estimated from a relationship between normalized downstream radioactivities and time. Results showed that the apparent permeability of albumin in the alveolar to pleural direction across the alveolar epithelial barrier is 2.3 X 10(-7) cm/s, significantly greater (P less than 0.0005) than that in the pleural to alveolar direction (5.3 X 10(-8) cm/s) when the tissue was short circuited. Permeability of inulin, on the other hand, did not show any directional dependence and averaged 3.1 X 10(-8) cm/s in both directions. There was no effect on radiotracer fluxes permeabilities of different electrical gradients across the tissue. Gel electrophoretograms and corresponding radiochromatograms suggest that the large and asymmetric isotope fluxes are not primarily due to digestion or degradation of labeled molecules. Inulin appears to traverse the alveolar epithelial barrier by simple diffusion through hydrated paracellular pathways. On the other hand, ( UC)albumin crosses the alveolar epithelium more rapidly than would be expected by simple diffusion. These asymmetric and large tracer fluxes suggest that a specialized mechanism is present in alveolar epithelium that may be capable of helping to remove albumin from the alveolar space.

Kim, K.J.; LeBon, T.R.; Shinbane, J.S.; Crandall, E.D.

1985-10-01

294

Asymmetric [14C]albumin transport across bullfrog alveolar epithelium  

International Nuclear Information System (INIS)

Bullfrog lungs were prepared as planar sheets and bathed with Ringer solution in Ussing chambers. In the presence of a constant electrical gradient (20, 0, or -20 mV) across the tissue, 14C-labeled bovine serum albumin or inulin was instilled into the upstream reservoir and the rate of appearance of the tracer in the downstream reservoir was monitored. Two lungs from the same animal were used to determine any directional difference in tracer fluxes. An apparent permeability coefficient was estimated from a relationship between normalized downstream radioactivities and time. Results showed that the apparent permeability of albumin in the alveolar to pleural direction across the alveolar epithelial barrier is 2.3 X 10(-7) cm/s, significantly greater (P less than 0.0005) than that in the pleural to alveolar direction (5.3 X 10(-8) cm/s) when the tissue was short circuited. Permeability of inulin, on the other hand, did not show any directional dependence and averaged 3.1 X 10(-8) cm/s in both directions. There was no effect on radiotracer fluxes permeabilities of different electrical gradients across the tissue. Gel electrophoretograms and corresponding radiochromatograms suggest that the large and asymmetric isotope fluxes are not primarily due to digestion or degradation of labeled molecules. Inulin appears to traverse the alveolar epithelial barrier by simple diffusion through hydrated paracellular pathways. On the other hand, [14C]albumin crosseother hand, [14C]albumin crosses the alveolar epithelium more rapidly than would be expected by simple diffusion. These asymmetric and large tracer fluxes suggest that a specialized mechanism is present in alveolar epithelium that may be capable of helping to remove albumin from the alveolar space

295

Partial pulmonary embolization disrupts alveolarization in fetal sheep  

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Full Text Available Abstract Background Although bronchopulmonary dysplasia is closely associated with an arrest of alveolar development and pulmonary capillary dysplasia, it is unknown whether these two features are causally related. To investigate the relationship between pulmonary capillaries and alveolar formation, we partially embolized the pulmonary capillary bed. Methods Partial pulmonary embolization (PPE was induced in chronically catheterized fetal sheep by injection of microspheres into the left pulmonary artery for 1 day (1d PPE; 115d gestational age; GA or 5 days (5d PPE; 110-115d GA. Control fetuses received vehicle injections. Lung morphology, secondary septal crests, elastin, collagen, myofibroblast, PECAM1 and HIF1? abundance and localization were determined histologically. VEGF-A, Flk-1, PDGF-A and PDGF-R? mRNA levels were measured using real-time PCR. Results At 130d GA (term ~147d, in embolized regions of the lung the percentage of lung occupied by tissue was increased from 29 ± 1% in controls to 35 ± 1% in 1d PPE and 44 ± 1% in 5d PPE fetuses (p VEGF and Flk-1, although a small increase in PDGF-R? expression at 116d GA, from 1.00 ± 0.12 in control fetuses to 1.61 ± 0.18 in 5d PPE fetuses may account for impaired differentiation of alveolar myofibroblasts and alveolar development. Conclusions PPE impairs alveolarization without adverse systemic effects and is a novel model for investigating the role of pulmonary capillaries and alveolar myofibroblasts in alveolar formation.

Hooper Stuart B

2010-04-01

296

Assessment of global morphological and topological changes in trabecular structure under the bone resorption process  

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Osteoporosis is a frequent skeletal disease characterised both by loss of bone mineral mass and deterioration of cancellous bone micro-architecture. It can be caused by mechanical disuse, estrogen deficiency or natural age-related resorption process. Numerical analysis of high-resolution images of the trabecular network is recognised as a powerful tool for assessment of structural characteristics. Using ?CT images of 73 thoracic and 78 lumbar human vertebral specimens in vitro with isotropic resolution of 26?m we simulate bone atrophy as random resorption of bone surface voxels. Global morphological and topological characteristics provided by four Minkowski Functionals (MF) are calculated for two numerical resorption models with and without conservation of global topological connectivity of the trabecular network, which simulates different types of bone loss in osteoporosis, as it has been described in males and females. Diagnostic performance of morphological and topological characteristics as a function of relative bone loss is evaluated by a correlation analysis with respect to experimentally measured Maximum Compressive Strength (MCS). In both resorption models the second MF, which coincides with bone surface fraction BS/TV, demonstrates almost constant value of Pearson's correlation coefficient with respect to the relative bone loss ?BV/TV. This morphological characteristic does not vary considerably under age-related random resorption and can be used for predicting bone strength in the elderly. The third and fourth MF demonstrate an increasing correlation coefficients with MCS after applying random bone surface thinning without preserving topological connectivity, what can be used for improvement of evaluation of the current state of the structure.

Sidorenko, Irina N.; Bauer, Jan; Monetti, Roberto; Baum, Thomas; Rummeny, Ernst J.; Eckstein, Felix; Matsuura, Maiko; Lochmueller, Eva-Maria; Zysset, Philippe K.; Raeth, Christoph W.

2012-03-01

297

Chronic pneumonia with Pseudomonas aeruginosa and impaired alveolar fluid clearance  

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Full Text Available Abstract Background While the functional consequences of acute pulmonary infections are widely documented, few studies focused on chronic pneumonia. We evaluated the consequences of chronic Pseudomonas lung infection on alveolar function. Methods P. aeruginosa, included in agar beads, was instilled intratracheally in Sprague Dawley rats. Analysis was performed from day 2 to 21, a control group received only sterile agar beads. Alveolar-capillary barrier permeability, lung liquid clearance (LLC and distal alveolar fluid clearance (DAFC were measured using a vascular (131I-Albumin and an alveolar tracer (125I-Albumin. Results The increase in permeability and LLC peaked on the second day, to return to baseline on the fifth. DAFC increased independently of TNF-? or endogenous catecholamine production. Despite the persistence of the pathogen within the alveoli, DAFC returned to baseline on the 5th day. Stimulation with terbutaline failed to increase DAFC. Eradication of the pathogen with ceftazidime did not restore DAFC response. Conclusions From these results, we observe an adequate initial alveolar response to increased permeability with an increase of DAFC. However, DAFC increase does not persist after the 5th day and remains unresponsive to stimulation. This impairment of DAFC may partly explain the higher susceptibility of chronically infected patients to subsequent lung injury.

Prangere Thierry

2005-02-01

298

Alveolar targeting of aerosol pentamidine. Toward a rational delivery system  

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Nebulizer systems that deposit a high proportion of aerosolized pentamidine on large airways are likely to be associated with marked adverse side effects, which may lead to premature cessation of treatment. We have measured alveolar deposition and large airway-related side effects (e.g., cough, breathlessness, and effect on pulmonary function) after aerosolization of 150 mg pentamidine isethionate labeled with 99mTc-Sn-colloid. Nine patients with AIDS were studied using three nebulizer systems producing different droplet size profiles: the Acorn System 22, Respirgard II, and Respirgard II with the inspiratory baffle removed. Alveolar deposition was greatest and side effects least with the nebulizer producing the smallest droplet size profile (Respirgard II), whereas large airway-related side effects were prominent and alveolar deposition lowest with the nebulizer producing the largest droplet size (Acorn System 22). Values for alveolar deposition and adverse airway effects were intermediate using the Respirgard with inspiratory baffle removed, thus indicating the importance of the baffle valve in determining droplet size. Addition of a similar baffle valve to the Acorn System 22 produced a marked improvement in droplet size profile. Selection of a nebulizer that produces an optimal droplet size range offers the advantage of enhancing alveolar targeting of aerosolized pentamidine while reducing large airway-related side effectside effects

299

A supra-cellular model for coupling of bone resorption to formation during remodeling: lessons from two bone resorption inhibitors affecting bone formation differently.  

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The bone matrix is maintained functional through the combined action of bone resorbing osteoclasts and bone forming osteoblasts, in so-called bone remodeling units. The coupling of these two activities is critical for securing bone replenishment and involves osteogenic factors released by the osteoclasts. However, the osteoclasts are separated from the mature bone forming osteoblasts in time and space. Therefore the target cell of these osteoclastic factors has remained unknown. Recent explorations of the physical microenvironment of osteoclasts revealed a cell layer lining the bone marrow and forming a canopy over the whole remodeling surface, spanning from the osteoclasts to the bone forming osteoblasts. Several observations show that these canopy cells are a source of osteoblast progenitors, and we hypothesized therefore that they are the likely cells targeted by the osteogenic factors of the osteoclasts. Here we provide evidence supporting this hypothesis, by comparing the osteoclast-canopy interface in response to two types of bone resorption inhibitors in rabbit lumbar vertebrae. The bisphosphonate alendronate, an inhibitor leading to low bone formation levels, reduces the extent of canopy coverage above osteoclasts. This effect is in accordance with its toxic action on periosteoclastic cells. In contrast, odanacatib, an inhibitor preserving bone formation, increases the extent of the osteoclast-canopy interface. Interestingly, these distinct effects correlate with how fast bone formation follows resorption during these respective treatments. Furthermore, canopy cells exhibit uPARAP/Endo180, a receptor able to bind the collagen made available by osteoclasts, and reported to mediate osteoblast recruitment. Overall these observations support a mechanism where the recruitment of bone forming osteoblasts from the canopy is induced by osteoclastic factors, thereby favoring initiation of bone formation. They lead to a model where the osteoclast-canopy interface is the physical site where coupling of bone resorption to bone formation occurs. PMID:24333871

Jensen, Pia Rosgaard; Andersen, Thomas Levin; Pennypacker, Brenda L; Duong, Le T; Engelholm, Lars H; Delaissé, Jean-Marie

2014-01-10

300

A supra-cellular model for coupling of bone resorption to formation during remodeling : Lessons from two bone resorption inhibitors affecting bone formation differently  

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The bone matrix is maintained functional through the combined action of bone resorbing osteoclasts and bone forming osteoblasts, in so-called bone remodeling units. The coupling of these two activities is critical for securing bone replenishment and involves osteogenic factors released by the osteoclasts. However, the osteoclasts are separated from the mature bone forming osteoblasts in time and space. Therefore the target cell of these osteoclastic factors has remained unknown. Recent explorations of the physical microenvironment of osteoclasts revealed a cell layer lining the bone marrow and forming a canopy over the whole remodeling surface, spanning from the osteoclasts to the bone forming osteoblasts. Several observations show that these canopy cells are a source of osteoblast progenitors, and we hypothesized therefore that they are the likely cells targeted by the osteogenic factors of the osteoclasts. Here we provide evidence supporting this hypothesis, by comparing the osteoclast-canopy interface in response to two types of bone resorption inhibitors in rabbit lumbar vertebrae. The bisphosphonate alendronate, an inhibitor leading to low bone formation levels, reduces the extent of canopy coverage above osteoclasts. This effect is in accordance with its toxic action on periosteoclastic cells. In contrast, odanacatib, an inhibitor preserving bone formation, increases the extent of the osteoclast-canopy interface. Interestingly, these distinct effects correlate with how fast bone formation follows resorption during these respective treatments. Furthermore, canopy cells exhibit uPARAP/Endo180, a receptor able to bind the collagen made available by osteoclasts, and reported to mediate osteoblast recruitment. Overall these observations support a mechanism where the recruitment of bone forming osteoblasts from the canopy is induced by osteoclastic factors, thereby favoring initiation of bone formation. They lead to a model where the osteoclast-canopy interface is the physical site where coupling of bone resorption to bone formation occurs.

Jensen, Pia Rosgaard; Andersen, Thomas Levin

2013-01-01

 
 
 
 
301

A supra-cellular model for coupling of bone resorption to formation during remodeling : lessons from two bone resorption inhibitors affecting bone formation differently  

DEFF Research Database (Denmark)

The bone matrix is maintained functional through the combined action of bone resorbing osteoclasts and bone forming osteoblasts, in so-called bone remodeling units. The coupling of these two activities is critical for securing bone replenishment and involves osteogenic factors released by the osteoclasts. However, the osteoclasts are separated from the mature bone forming osteoblasts in time and space. Therefore the target cell of these osteoclastic factors has remained unknown. Recent explorations of the physical microenvironment of osteoclasts revealed a cell layer lining the bone marrow and forming a canopy over the whole remodeling surface, spanning from the osteoclasts to the bone forming osteoblasts. Several observations show that these canopy cells are a source of osteoblast progenitors, and we hypothesized therefore that they are the likely cells targeted by the osteogenic factors of the osteoclasts. Here we provide evidence supporting this hypothesis, by comparing the osteoclast-canopy interface in response to two types of bone resorption inhibitors in rabbit lumbar vertebrae. The bisphosphonate alendronate, an inhibitor leading to low bone formation levels, reduces the extent of canopy coverage above osteoclasts. This effect is in accordance with its toxic action on periosteoclastic cells. In contrast, odanacatib, an inhibitor preserving bone formation, increases the extent of the osteoclast-canopy interface. Interestingly, these distinct effects correlate with how fast bone formation follows resorption during these respective treatments. Furthermore, canopy cells exhibit uPARAP/Endo180, a receptor able to bind the collagen made available by osteoclasts, and reported to mediate osteoblast recruitment. Overall these observations support a mechanism where the recruitment of bone forming osteoblasts from the canopy is induced by osteoclastic factors, thereby favoring initiation of bone formation. They lead to a model where the osteoclast-canopy interface is the physical site where coupling of bone resorption to bone formation occurs.

Jensen, Pia Rosgaard; Andersen, Thomas Levin

2014-01-01

302

Structural requirements for the action of parathyroid hormone-related protein (PTHrP) on bone resorption by isolated osteoclasts  

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Parathyroid hormone-related protein (PTHrP) plays a major role in the syndrome of humoral hypercalcemia of malignancy (HHM) by its actions on bone and kidney. In this study an isolated osteoclast bone resorption assay was used to investigate the actions of this peptide and the structure-activity relationships for its resorption effect. As with PTH, neither synthetic nor recombinant PTHrP preparations stimulated resorption within highly purified osteoclast populations. Resorption was stimulated only in the presence of contaminating osteoblasts or in cocultures with the osteoblast-like cell line UMR-106. In the presence of osteoblasts PTHrP-(1-34) and PTHrP-(1-84) stimulated bone resorption in a dose-dependent manner with a potency comparable to that of PTH-(1-34) on a molar basis. The biologic activity of the PTHrP was shown to reside in the first 34 amino acids, and within that region the structural requirements for promotion of osteoclastic resorption resembled closely those for promotion of cyclic AMP formation in osteoblast-like cells. Using emulsion autoradiography with iodinated PTHrP-(1-34) and PTHrP-(1-84) on mixed bone cell preparations from neonatal rats, specific binding was demonstrated only to osteoblasts, not to osteoclasts. These results clearly demonstrate that PTHrP is a potent stimulator of bone resorption and that these effects are, like those of PTH, mediated by initial actions upon cells of the osteoblast lineage.

Evely, R.S.; Bonomo, A.; Schneider, H.G.; Moseley, J.M.; Gallagher, J.; Martin, T.J. (St. Vincent' s Institute of Medical Research, Melbourne (Australia))

1991-01-01

303

A young non-immunocompromised woman with diffuse alveolar opacities  

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Full Text Available Diffuse alveolar opacities (DAO due to pulmonary tuberculosis are usually described in immunocompromised patients. In adult patients residing in high endemic areas such as India, alveolar opacities are not reported frequently in non-immunocompromised pulmonary tuberculosis patients. We describe a twenty-five-year-old woman who presented with bilateral diffuse alveolar opacities and initial diagnostic work up was directed to non-tuberculosis etiologies. Her sputum was not suggestive of tuberculous or any other infective etiology. However, histopathological examination of specimen from fine needle aspiration cytology through percutaneous route suggested chronic granulomatous disease with detection of mycobacterium. Polymerase chain reaction test in BAL and FNAC specimen confirmed tubercular etiology. Though not frequent, pulmonary tuberculous etiology is worth considering in the differential diagnosis of DAO as not only tuberculosis is fully treatable but also early detection shall help to avoid unnecessary invasive tests and cut down transmission to contacts.

Gupta Prem

2010-01-01

304

Alveolar rhabdomyosarcoma involving the mandibular ramus and its surrounding tissues  

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Rhabdomyosarcoma, when it occurs in the head and neck, is primarily found in children. Alveolar rhabdomyosarcoma is rarely seen in the oral lesion, comparing to the embryonal and the pleomorphic variants. This is a report of a case of alveolar rhabdomyosarcoma in the mandible in a ten-year old girl who complained of a non-painful swelling on the right cheek. The right lower 1st molar was mobile. Her radiographs revealed an extensive radiolucency with somewhat irregular border on the right mandibular ramus. The right mandibular 1st and 2nd molars lost their lamina dura and were floating. CT images revealed smooth-outlined soft tissue mass occupying the pterygomandibular space, the infratemporal space, and the masseteric muscle with thinning and perforation of the right mandibular angle and ramus. Histopathological and immunohistochemical findings established the final diagnosis of alveolar rhabdomyosarcoma.

305

Alveolar rhabdomyosarcoma involving the mandibular ramus and its surrounding tissues  

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Rhabdomyosarcoma, when it occurs in the head and neck, is primarily found in children. Alveolar rhabdomyosarcoma is rarely seen in the oral lesion, comparing to the embryonal and the pleomorphic variants. This is a report of a case of alveolar rhabdomyosarcoma in the mandible in a ten-year old girl who complained of a non-painful swelling on the right cheek. The right lower 1st molar was mobile. Her radiographs revealed an extensive radiolucency with somewhat irregular border on the right mandibular ramus. The right mandibular 1st and 2nd molars lost their lamina dura and were floating. CT images revealed smooth-outlined soft tissue mass occupying the pterygomandibular space, the infratemporal space, and the masseteric muscle with thinning and perforation of the right mandibular angle and ramus. Histopathological and immunohistochemical findings established the final diagnosis of alveolar rhabdomyosarcoma.

Yoon, Suk Ja; Kang, Byung Cheol [Chonnam National University College of Medicine, Gwangju (Korea, Republic of)

2004-06-15

306

Hypothermic insult to the periodontium: a model for the study of aseptic tooth resorption.  

Science.gov (United States)

The aim of the current investigation was to define an animal model for the study of hard tissue resorption by examining the responses of the periodontal ligament (PDL) to both single and multiple episodes of hypothermic injury to the crowns of rat teeth. A group of 12 male rats weighing 200-250 g were anesthetized, and pellets of dry ice (CO2) were applied once to the crowns of the right first maxillary molars for continuous periods of 10 or 20 min. Animals were sacrificed at 2, 7, 14 and 28 days and tissues were processed for routine histological examination. A second group of eight animals and a third group of 12 animals were subjected to three applications of dry ice over a period of 1 week and sacrificed at 2 and 14 days respectively after the final application. In addition to thermal insult, the periodontium of teeth from a fourth group of six rats was subjected to mechanical trauma. Examination of the sections from the group undergoing a single freezing episode revealed that, by 1 week, shallow resorption lacunae had appeared on the root surface. These became more extensive after 14 days. At the same time hyaline degeneration was evident in the PDL. Within this group, teeth subjected to the longer 20-min application times generally showed more extensive injuries. By 28 days, evidence of repair was observed with reparative cementum beginning to line the resorption lacunae in the root dentin. Sections from animals subjected to multiple episodes of thermal trauma and those subjected to additional mechanical insult showed more extensive external root resorption than those from single-injury animals. It was concluded that low temperature stimuli applied to the crowns of rat molars were capable of eliciting a sterile degenerative response in the PDL which, in turn, resulted in external root resorption. Furthermore, the degree of this tissue injury was commensurate with the duration and number of exposures to the trauma. The results also indicated that progression of the resorptive process required periodic exposure to the injury, in the absence of which repair to the damaged root occurred. PMID:11202857

Dreyer, C W; Pierce, A M; Lindskog, S

2000-02-01

307

Characterization of the bone-resorptive effect of interleukin-11 in cultured mouse calvarial bones.  

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Interleukin-11 (IL-11) is a stromal cell-derived cytokine that can enhance osteoclast formation and stimulate bone resorption. In the present study, the characteristics of the resorptive effect of IL-11 in mouse calvarial bones were investigated. Both recombinant mouse IL-11 and human IL-11 caused concentration- and time-dependent stimulations of (45)Ca release from prelabeled mouse calvariae. Half-maximal responses were obtained at 0.7 ng/mL (approximately 40 pmol/L). Mouse and human IL-11 also stimulated release of (3)H from [(3)H]-proline-labeled bones. The magnitude of the (45)Ca and (3)H release (1.4-1.6-fold) caused by a maximally effective concentration of IL-11 was less than the stimulation (2.5-4.0-fold) elicited by a maximum concentration of parathyroid hormone (PTH). Release of (45)Ca by IL-11 was unaffected by the mitotic inhibitors, hydroxyurea and aphidicolin. In addition to resorption of bone, IL-11 caused a small (1.5-2.0-fold) enhancement of prostaglandin E(2) (PGE(2)) biosynthesis in calvariae, but had no effect on the mRNA expression of cyclooxygenase-1 and -2, or cytosolic phospholipase A(2). Indomethacin and flurbiprofen abolished the formation of PGE(2) and partially reduced (45)Ca release stimulated by IL-11. When either mouse interleukin-4 (IL-4) or interleukin-13 (IL-13) was added to calvariae treated with IL-11, (45)Ca release was inhibited. Resorption caused by IL-11 was also inhibited by both anti-mouse glycoprotein 130 (gp130) and an antibody neutralizing IL-11, but these agents had no effect on (45)Ca release caused by PTH or 1,25(OH)(2)vitamin D(3) (D(3)). Real-time, quantitative polymerase chain reaction (PCR) analysis (TaqMan PCR) and semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) demonstrated that IL-11 caused concentration-dependent enhancements of receptor activator of nuclear factor-kappaB ligand (RANKL) and osteoprotegerin (OPG) mRNA, without affecting the mRNA expression of RANK. Mouse RANKL stimulated (45)Ca release in the calvarial bones. The stimulatory effects of RANKL and IL-11 were inhibited by mouse OPG. These data demonstrate that IL-11 stimulates osteoclastic resorption in mouse calvariae by mechanisms that are independent of cell proliferation; partially dependent on prostaglandin biosynthesis; sensitive to inhibition by IL-4, IL-13, and OPG; and associated with enhanced expression of RANKL and OPG. In addition, IL-11 was not found to play an essential role in resorption stimulated by other calciotropic agents in calvariae. PMID:12110441

Ahlen, J; Andersson, S; Mukohyama, H; Roth, C; Bäckman, A; Conaway, H H; Lerner, U H

2002-07-01

308

Alveolar macrophage kinetics and function after interruption of canine marrow function  

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To study the kinetics and function of alveolar macrophages after interruption of marrow function, we performed serial bronchoalveolar lavages in dogs. The studies were performed before and after 9.0 to 9.5 Grey total body irradiation and marrow infusion. Monocytes had disappeared from the bloodstream by Day 7 after the irradiation. Alveolar macrophages were significantly decreased at Day 21. At Days 14 and 21 myeloperoxidase-positive alveolar macrophages were also significantly decreased. Beyond Day 30 the number of circulating monocytes, myeloperoxidase-positive and total alveolar macrophages had returned. Sex chromatin stains of alveolar macrophages obtained from a male dog that received female marrow indicated that the repopulating macrophages were of marrow origin. In vitro studies of alveolar macrophage migration and phagocytosis demonstrated increased activities beyond Day 30. These studies suggest that in this model the alveolar macrophage is dependent on the bone marrow for support and that the alveolar macrophage depletion may impair lung defense mechanisms

309

Poliangeíte microscópica com hemorragia alveolar difusa / Microscopic polyangiitis with diffuse alveolar hemorrhage  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Poliangeíte microscópica é uma forma de vasculite sistêmica de pequenos vasos, associada aos anticorpos anticitoplasma de neutrófilos, que preferencialmente acomete vênulas, capilares e arteríolas, e que pode, entretanto, envolver artérias e veias. Está entre as vasculites sistêmicas primárias de pe [...] quenos vasos mais freqüentes, e pode ter apresentação clínica indistinguível da granulomatose de Wegener e da síndrome de Churg-Strauss. Estas vasculites de pequenos vasos são histologicamente semelhantes e podem ser diferenciadas pela presença de granulomas na granulomatose de Wegener, ou de quadro clínico-funcional de asma na síndrome de Churg-Strauss. Relata-se o caso de um paciente do sexo masculino de 66 anos com poliangeíte microscópica com hemorragia alveolar difusa como forma de apresentação clínica, com ênfase no diagnóstico diferencial com outras vasculites pulmonares de pequenos vasos. Abstract in english Microscopic Polyangiitis is a form of Anti-Neutrophil Cytoplasmic Antibody (ANCA)- associated small-vessel vasculitis that preferentially involves venules, capillaries and arterioles and may also involve arteries and veins. It is one of the most common primary systemic small-vessel vasculitis. Its c [...] linical presentation is not distinguishable from the Wegener’s granulomatosis (WG) and the Churg-Strauss syndrome (CSS). These types of small-vessel vasculitis are histologically similar and can be differentiated by the presence of granulomatous inflammation in WG or asthma in CSS. The case of a 66-year-old man with microscopic polyangiitis presenting with alveolar hemorrhage is reported with a discussion of the differential diagnosis of other types of pulmonary small-vessel vasculitis.

José Wellington Alves dos, Santos; Gustavo Trindade, Michel; Carlos Eurico da Luz, Pereira; Vera Luiza, Capelozzi; Jader Nascimento, Mileto; Cleber Antonio, Fiorini.

310

Alveolar epithelial permeability in bronchial asthma in children  

International Nuclear Information System (INIS)

To evaluate alveolar epithelial permeability (kep) in children with bronchial asthma, 99mTc-DTPA (diethylene triamine penta acetate) aerosol lung inhalation scintigraphies were performed. There was no correlation between the kep value and the severity of asthma. On the other hand, out of 10 cases which had no aerosol deposition defect in the lung field, 4 showed high kep values on the whole lung field and 7 had high kep value areas, particularly apparent in the upper lung field. These results suggest that even when the central airway lesions are mild, severe damage exists in the alveolar region of the peripheral airway. (author)

311

From alveolar diffuse atrophy to aggressive periodontitis: a brief history.  

Science.gov (United States)

Technologic advances in mechanics, electronics, physics, chemistry, and computer science have contributed to advances in dental medicine. Periodontology is not only a clinical science but is also directly related to the basic sciences. Research is conducted in laboratories rather than in clinics now. During the last century, aggressive periodontitis has received attention from numerous researchers because of its multifactorial features. This paper explores the long scientific journey of aggressive periodontitis, beginning with its first definition as alveolar diffuse atrophy. Perhaps in the future, "alveolar diffuse atrophy" will be referred to by another name or term. However, this journey will never end. PMID:17354672

Guzeldemir, Esra; Toygar, Hilal Uslu

2006-01-01

312

Pulmonary alveolar microlithiasis and probe-based confocal laser endomicroscopy.  

Science.gov (United States)

Pulmonary alveolar microlithiasis (PAM) is a rare disease in which calcium-phosphate microliths accumulate within the alveolar space. We report cases of 2 siblings with PAM, presenting differently as regards the distribution and clinical severity. Immune cytologic analysis of bronchoalveolar lavage showed a CD4 alveolitis in the radiologically most affected patient, whereas the least affected had a normal bronchoalveolar lavage analysis, demonstrating the low specificity of immune cytologic lavage analysis in diagnosing familial PAM. For the first time, we describe the endoscopic findings using a probe-based confocal laser endomicroscopy. PMID:23609253

Yserbyt, Jonas; Alamé, Touffic; Dooms, Christophe; Ninane, Vincent

2013-04-01

313

Superoxide dismutase protects against apoptosis and alveolar enlargement induced by ceramide  

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The molecular events leading to emphysema development include generation of oxidative stress and alveolar cell apoptosis. Oxidative stress upregulates ceramides, proapoptotic signaling sphingolipids that trigger further oxidative stress and alveolar space enlargement, as shown in an experimental model of emphysema due to VEGF blockade. As alveolar cell apoptosis and oxidative stress mutually interact to mediate alveolar destruction, we hypothesized that the oxidative stress generated by ceram...

Petrache, Irina; Medler, Terry R.; Richter, Amy T.; Kamocki, Krzysztof; Chukwueke, Ugonma; Zhen, Lijie; Gu, Yuan; Adamowicz, Jeremy; Schweitzer, Kelly S.; Hubbard, Walter C.; Berdyshev, Evgeny V.; Lungarella, Giuseppe; Tuder, Rubin M.

2008-01-01

314

DMPD: Silica binding and toxicity in alveolar macrophages. [Dynamic Macrophage Pathway CSML Database  

Full Text Available 18226603 Silica binding and toxicity ... in alveolar macrophages. Hamilton RF Jr, Thakur SA, Holian ... ng) (.svg) (.html) (.csml) Show Silica binding and toxicity ... in alveolar macrophages. PubmedID 18226603 Title S ... ilica binding and toxicity ... in alveolar macrophages. Authors Hamilton RF Jr, T ...

315

Hemorragia alveolar masiva por citomegalovirus (CMV) e infección por VIH / Massive alveolar hemorrhage due to cytomegalovirus (CMV) and HIV infection  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish La hemorragia alveolar puede ser la complicación de enfermedades con manifestaciones locales y sistémicas, ambas comparten el mismo concepto fisiopatológico: daño a la microcirculación alveolar. Es una entidad clínica que genera un reto diagnóstico para el médico. El reconocimiento oportuno favorece [...] un tratamiento agresivo, con lo que puede mejorar el pronóstico. A pesar de los avances tecnológicos en el diagnóstico y tratamiento, se mantiene como una condición de elevada morbilidad y mortalidad. Se presenta el caso de una mujer de 42 años con diagnóstico de hemorragia alveolar masiva por citomegalovirus (CMV) e infección por VIH. La forma de presentación es atípica debido a que la mayoría de los casos reportados se presentan como proceso neumónico, siendo infrecuentes los episodios de hemorragia masiva. El diagnóstico se documentó mediante broncoscopia con lavado broncoalveolar y el diagnóstico etiológico con técnicas moleculares utilizando la reacción en cadena de la polimerasa en transcriptasa reversa. Abstract in english Alveolar hemorrhage may be a complication of diseases with local and systemic manifestations. Both share the same pathophysiological concept: damage to the alveolar microcirculation. It is a clinical entity that generates a diagnostic challenge for the physician. Early recognition favors aggressive [...] treatment, which can improve the outcome. Despite the technological advances in its diagnosis and treatment, it is still a condition having high morbidity and mortality. We present the case of a 42-year old woman diagnosed of massive alveolar hemorrhage induced by cytomegalovirus (CMV) and HIV infection. Its presentation is atypical because most reported cases have occurred as a pneumonic process, episodes of massive hemorrhage being uncommon. The diagnosis was documented by bronchoscopy with bronchoalveolar lavage and etiological diagnosis with molecular techniques using reverse transcription polymerase chain reaction.

A., Cortés; E., Peña; R., Vega; G., Reyes; E., Bautista.

316

Etiology and prevention of external cervical root resorption associated to teeth bleaching  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction and objective: Esthetic dentistry has been prioritizedand the desire for whiter teeth has been increasingly present in dental offices, since whiter teeth tend to indicate health, beauty, youth and a more attractive smile. Teeth bleaching is a conservative method widely used to restore the original color of darkened teeth. However, possible relations with the external cervical root resorption have concerned many researchers and clinicians. Literature review: There are many mechanisms that can activate the external cervical root resorption, such as: chemical and physical action of the bleaching materials used, morphology of the cementoenamel junction associated to the immune system, material concentration, traumas and bleaching technique used. Conclusion: Therefore, considering many factors that are still not conclusive, preventing deleterious effects on teeth and support structures, care must be taken when choosing bleaching agent and bleaching technique, as well as when selecting each case, beyond a proper restoration after teeth bleaching.

Eliane Mendes da SILVA

2010-03-01

317

Prosthodontic rehabilitation of a patient diagnosed with multiple idiopathic root resorption.  

Science.gov (United States)

A female college student was referred by her general dentist for evaluation of the interproximal caries-like lesions discovered during her biannual visit. The lesions were determined to result from external resorption of unknown origin. After the most affected teeth had been extracted and the other teeth were restored after periodontal surgery, an interim partial removable dental prosthesis was placed. Two months later, the resorption pattern had proliferated to the rest of her dentition, thus revising the treatment plan to involve full mouth extractions and to place immediate maxillary and mandibular complete removable dental prostheses. Subsequently, 6 titanium dental implants were placed in each arch, and, after healing, opposing metal ceramic screw-retained fixed dental prostheses were inserted. PMID:24120211

Haeberle, C Brent

2013-12-01

318

Management of recurrent fracture of central incisor with internal resorption using light transmitting (luminex post  

Directory of Open Access Journals (Sweden)

Full Text Available The normal root canal anatomy may be altered in various pathological processes and making it very difficult and at times impossible to achieve ideal obturation by normal methods. Internal resorption is one among them. There are several treatment protocols advised for this pathological condition. A crown-root fracture is defined as a fracture involving enamel, dentin and cementum and accounts for 5% of all traumatic injuries to the permanent dentition. In anterior teeth, these fractures are usually caused by direct trauma and often complicated in fully erupted teeth. In cases where the fracture line extends down along the long axis of the root, extraction of the tooth is indicated. The purpose of this report is to present the use of light transmitting post system to reinforce the crown root fractured maxillary central incisor due to trauma and internal resorption.

Hariharan V

2010-01-01

319

Role of mineral trioxide aggregate in management of external root resorption  

Science.gov (United States)

External root resorption (ERR) is a lytic process occurring in the cementum or cementum and dentin of the roots of teeth. Here we report a case of inflammatory ERR in a mandibular right molar in a 22-year-old male patient with history of incomplete root canal treatment with the same. Considering the biological properties of mineral trioxide aggregate cement, especially its alkalinity and sustained calcium hydroxide release, this material was used for the treatment of ERR, followed by permanent prosthesis. The clinical and radiographic follow-up for 24 months revealed that treated teeth were functional, the progression of the ERR had ceased, the resorptive area were replaced with newly formed bone and periapical radiolucencies was healed. PMID:24347899

Ashwini, TS; Hosmani, Namrata; Patil, Chetan R; Yalgi, Viraj S

2013-01-01

320

Study on bone resorption behavior of osteoclast under drug effect using 41Ca tracing  

Science.gov (United States)

The mechanisms governing calcium fluxes during bone remodeling processes in Osteoporosis (OP) patients are poorly known. Understanding the changes of Osteoclasts (OC) during this dynamic transition is important to prevent and cure OP. The exploration of long-lived 41Ca (T1/2 = 1.04 × 105 years) tracer combined with AMS measurements leads to the possibility of monitoring the bone resorption behavior of OC in OP patients. In this work, the behavior of OC with the administration of Strontium Ranelate (SR), a drug for OP, was studied by using 41Ca labeled hydroxyapatite (HAP) to simulate the bone. AMS on the HI-13 tandem accelerator at CIAE was used to determine trace amounts of 41Ca. The results show that the technique of 41Ca tracing with AMS can be used to quantitatively monitor the behavior of OC in bone resorption under the effects of drugs. Experimental details and preliminary results will be presented.

Kejun, Dong; Liyan, Lu; Ming, He; Yinggen, Ouyang; Yan, Xue; Chaoli, Li; Shaoyong, Wu; Xianggao, Wang; Hongtao, Shen; Jianjun, Gao; Wei, Wang; Dafu, Chen; Yonggang, Xing; Jian, Yuan; Shan, Jiang

2013-01-01

 
 
 
 
321

Study on bone resorption behavior of osteoclast under drug effect using 41Ca tracing  

International Nuclear Information System (INIS)

The mechanisms governing calcium fluxes during bone remodeling processes in Osteoporosis (OP) patients are poorly known. Understanding the changes of Osteoclasts (OC) during this dynamic transition is important to prevent and cure OP. The exploration of long-lived 41Ca (T1/2 = 1.04 × 105 years) tracer combined with AMS measurements leads to the possibility of monitoring the bone resorption behavior of OC in OP patients. In this work, the behavior of OC with the administration of Strontium Ranelate (SR), a drug for OP, was studied by using 41Ca labeled hydroxyapatite (HAP) to simulate the bone. AMS on the HI-13 tandem accelerator at CIAE was used to determine trace amounts of 41Ca. The results show that the technique of 41Ca tracing with AMS can be used to quantitatively monitor the behavior of OC in bone resorption under the effects of drugs. Experimental details and preliminary results will be presented.

322

Nitrogen and phosphorus resorption in a neotropical rain forest of a nutrient-rich soil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Costa Rica | Language: English Abstract in spanish En las selvas tropicales con suelos fértiles se ha observado que la reabsorción de nutrientes de los arboles de las hojas seniles no siempre es baja. Esta falta de consistencia en el resultado es talvez debida en parte a la metodología de reabsorción de nutrientes utilizada. El objetivo de este estu [...] dio fue analizar la reabsorción final de N y P de arboles de la selva húmeda tropical en un suelo rico en nutrientes. La hipótesis planteada fue que en un suelo rico en nutrientes los arboles presentarían una baja reabsorción final de nutrientes. En 30 muestras del suelo superficial (10 cm) de tres sitios de la selva no perturbada, se analizó entre otras características físicas y químicas, la concentración de N total y P extraíble. A través de la concentración de N y P en hojas seniles, se determinó la reabsorción real de 11 especies dominantes de arboles de esta selva. El N se analizó por digestión microkjeldahl con ácido sulfúrico y destilación con ácido bórico, y el P se analizó por digestión con ácido nítrico y destilación con perclórico. El suelo fue rico en N total (0.50%, n = 30) y P extraíble (4.11 µg g-1, n = 30). Tal como se esperaba, los arboles mostraron una reabsorción incompleta para el N (1.13%, n = 11) y P (0.11%, n = 11). Abstract in english In tropical forests with nutrient-rich soil tree’s nutrient resorption from senesced leaves has not always been observed to be low. Perhaps this lack of consistence is partly owing to the nutrient resorption methods used. The aim of the study was to analyse N and P resorption proficiency from tropic [...] al rain forest trees in a nutrient-rich soil. It was hypothesised that trees would exhibit low nutrient resorption in a nutrient-rich soil. The soil concentrations of total N and extractable P, among other physical and chemical characteristics, were analysed in 30 samples in the soil surface (10 cm) of three undisturbed forest plots at ‘Estación de Biología Los Tuxtlas’ on the east coast of Mexico (18°34’ - 18°36’ N, 95°04’ - 95°09’ W). N and P resorption proficiency were determined from senescing leaves in 11 dominant tree species. Nitrogen was analysed by microkjeldahl digestion with sulphuric acid and distilled with boric acid, and phosphorus was analysed by digestion with nitric acid and perchloric acid. Soil was rich in total N (0.50%, n = 30) and extractable P (4.11 µg g-1, n = 30). As expected, trees showed incomplete N (1.13%, n = 11) and P (0.11%, n = 11) resorption. With a more accurate method of nutrient resorption assessment, it is possible to prove that a forest community with a nutrient-rich soil can have low levels of N and P resorption. Rev. Biol. Trop. 53(3-4): 353-359. Epub 2005 Oct 3.

José Luis, Martínez-Sánchez.

2005-09-01

323

Apical root resorption caused by orthodontic forces: A brief review and a long-term observation  

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External apical root resorption (ARR) is a common iatrogenic consequence of orthodontic treatment. One of the aims of this article is to present a brief overview of the literature, including; diagnosis and etiology, with emphasis on orthodontic forces to facilitate an understand of the prevention or management of ARR in orthodontic patients. We also present a long-term follow-up observation of severe ARR, including the last obtained cone beam computed tomography (CBCT) records, to demonstrate...

Topkara, Ahu; Karaman, Ali I.; Kau, Chung H.

2012-01-01

324

Etiology and prevention of external cervical root resorption associated to teeth bleaching  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Introduction and objective: Esthetic dentistry has been prioritizedand the desire for whiter teeth has been increasingly present in dental offices, since whiter teeth tend to indicate health, beauty, youth and a more attractive smile. Teeth bleaching is a conservative method widely used to restore the original color of darkened teeth. However, possible relations with the external cervical root resorption have concerned many researchers and clinicians. Literature review: There are many mechani...

Silva, Eliane Mendes Da; Leonardi, Denise Piotto; Haragushiku, Gisele Aihara; Tomazinho, Fla?via Sens Fagundes; Baratto Filho, Flares; Zielak, Joa?o Ce?sar

2010-01-01

325

Accuracy of Digital Subtraction Radiography in detection of artificial external root resorption (in vitro)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Introduction: External root resorption refers to the loss of cementum and/or dentin from the rootof the teeth. 40% mineral loss occur in conventional radiographies but digital subtractionradiography is capable of localizing a lesion with only 1-5% mineral loss. This in vitro study aimedto determine the accuracy of digital subtraction radiography in diagnosis of simulated external rootresorption.Methods and Materials: Ten premolar teeth with clinically intact roots were used were fixed insuita...

Ghafari, R.; Keshavarzi, M.

2008-01-01

326

Estrogen directly attenuates human osteoclastogenesis, but has no effect on resorption by mature osteoclasts  

DEFF Research Database (Denmark)

Estrogen deficiency arising with the menopause promotes marked acceleration of bone resorption, which can be restored by hormone replacement therapy. The inhibitory effects of estrogen seem to involve indirect cytokine- mediated effects via supporting bone marrow cells, but direct estrogen-receptor mediated effects on the bone-resorbing osteoclasts have also been proposed. Little information is available on whether estrogens modulate human osteoclastogenesis or merely inhibit the functional activity of osteoclasts. To clarify whether estrogens directly modulate osteoclastic activities human CD14+ monocytes were cultured in the presence of M-CSF and RANKL to induce osteoclast differentiation. Addition of 0.1-10 nM 17beta-estradiol to differentiating osteoclasts resulted in a dose-dependent reduction in tartrate resistant acid phosphatase (TRACP) activity reaching 60% at 0.1 nM. In addition, 17beta-estradiol inhibited bone resorption, as measured by the release of the C-terminal crosslinked telopeptide (CTX), by 60% at 0.1 nM, but had no effect on the overall cell viability. In contrast to the results obtained with differentiating osteoclasts, addition of 17beta-estradiol (0.001-10 nM) to mature osteoclasts did not affect bone resorption or TRACP activity. We investigated expression of the estrogen receptors, using immunocytochemistry and Western blotting. We found that ER-alpha is expressed in osteoclast precursors, whereas ER- beta is expressed at all stages, indicating that the inhibitory effect of estrogen on osteoclastogenesis is mediated by ER-alpha for the major part. In conclusion, these results suggest that the in vivo effects of estrogen are mediated by reduction of osteoclastogenesis rather than direct inhibition of the resorptive activity of mature osteoclasts.

SØrensen, M G; Henriksen, K

2006-01-01

327

Diagnosis of invasive cervical resorption by using cone beam computed tomography: report of two cases  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese A interpretação radiográfica é essencial para o diagnóstico da reabsorção cervical invasiva (RCI) e a dificuldade em distingui-la da reabsorção radicular interna tem sido destacada na literatura. Este trabalho relata o uso da tomografia computadorizada de feixe cônico (TCFC) no diagnóstico da RCI. O [...] s casos descrevem como a TCFC pode ser utilizada no diagnóstico diferencial e relatam também como esta tecnologia pode providenciar relevantes informações sobre a localização e natureza das reabsorções radiculares, limitadas pelas radiografias convencionais. Como resultado, o tratamento do canal radicular não foi inicialmente considerado. Os pacientes serão acompanhados e após curto período de tempo novos exames tomográficos serão realizados no intuito de detectar pequenas alterações. Observa-se que ambos os casos beneficiaram-se com o uso da TCFC no diagnóstico de RCI, pois esta modalidade de imagem determinou a real extensão da reabsorção e possíveis pontos de comunicação com o espaço periodontal. Abstract in english A radiographic interpretation is essential to the diagnosis of invasive cervical resorption (ICR) and the difficulty in distinguishing this lesion from internal root resorption has been highlighted in the literature. This paper reports the use of cone beam computed tomography (CBCT) in the diagnosis [...] of ICR. The cases reports describe how CBCT can be used to make a differential diagnosis and also show that the use of this technology can provide relevant information on the location and nature of root resorption, which conventional radiographs cannot. As a result, the root canal treatment was not initially considered. The patients will be monitored and will undergo a scan after a short period of time to detect any small changes. It was observed that both cases benefited from CBCT in the diagnosis of ICR, because this imaging modality determined the real extent of resorption and possible points of communication with the periodontal space.

Karla de Faria, Vasconcelos; Yuri, Nejaim; Francisco, Haiter Neto; Frab Norberto, Bóscolo.

2012-10-01

328

Relative contributions of testosterone and estrogen in regulating bone resorption and formation in normal elderly men  

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Young adult males who cannot produce or respond to estrogen (E) are osteopenic, suggesting that E may regulate bone turnover in men, as well as in women. Both bioavailable E and testosterone (T) decrease substantially in aging men, but it is unclear which deficiency is the more important factor contributing to the increased bone resorption and impaired bone formation that leads to their bone loss. Thus, we addressed this issue directly by eliminating endogenous T and E production in 59 elderl...

Falahati-nini, Alireza; Riggs, B. Lawrence; Atkinson, Elizabeth J.; O’fallon, W. Michael; Eastell, Richard; Khosla, Sundeep

2000-01-01

329

N-acetyl muramyl dipeptide stimulation of bone resorption in tissue culture.  

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N-Acetyl-muramyl-L-alanyl-D-isoglutamine (MDP), a structurally defined fragment of bacterial peptidoglycan, stimulated significant release of previously incorporated 45Ca from fetal rat bones in tissue culture over the concentration range of 0.1 to 10.0 micrograms/ml. MDP-Stimulated bone resorption was not inhibited by the addition of the prostaglandin synthetase inhibitor indomethacin to the culture medium. MDP was neither mitogenic for nor stimulated the release of osteoclast-activating fac...

Dewhirst, F. E.

1982-01-01

330

Mapping nutrient resorption efficiencies of subarctic cryptogams and seed plants onto the Tree of Life  

Science.gov (United States)

Nutrient resorption from senescing photosynthetic organs is a powerful mechanism for conserving nitrogen (N) and phosphorus (P) in infertile environments. Evolution has resulted in enhanced differentiation of conducting tissues to facilitate transport of photosynthate to other plant parts, ultimately leading to phloem. Such tissues may also serve to translocate N and P to other plant parts upon their senescence. Therefore, we hypothesize that nutrient resorption efficiency (RE, % of nutrient pool exported) should correspond with the degree of specialization of these conducting tissues across the autotrophic branches of the Tree of Life. To test this hypothesis, we had to compare members of different plant clades and lichens within a climatic region, to minimize confounding effects of climatic drivers on nutrient resorption. Thus, we compared RE among wide-ranging basal clades from the principally N-limited subarctic region, employing a novel method to correct for mass loss during senescence. Even with the limited numbers of species available for certain clades in this region, we found some consistent patterns. Mosses, lichens, and lycophytes generally showed low REN (70%). REP appeared higher in eudicots and liverworts than in mosses. Within mosses, taxa with more efficient conductance also showed higher REN. The differences in REN among clades broadly matched the degree of specialization of conducting tissues. This novel mapping of a physiological process onto the Tree of Life broadly supports the idea that the evolution of conducting tissues toward specialized phloem has aided land plants to optimize their internal nitrogen recycling. The generality of evolutionary lines in conducting tissues and nutrient resorption efficiency needs to be tested across different floras in different climatic regions with different levels of N versus P availability. PMID:25360262

Lang, Simone I; Aerts, Rien; van Logtestijn, Richard S P; Schweikert, Wenka; Klahn, Thorsten; Quested, Helen M; van Hal, Jurgen R; Cornelissen, Johannes H C

2014-01-01

331

Investigation of microscopic bone resorption in cortical Bone Multicellular Units using a lattice-based computational model  

CERN Document Server

Bone resorption by osteoclasts is an essential phase in the bone remodelling cycle as it creates the physiological conditions for subsequent bone formation. While several properties of osteoclastic bone resorption in cortical Bone Multicellular Units (BMU) have been assessed experimentally, the precise spatio-temporal dynamics, movement pattern, apoptotic state (single nuclei vs. whole cell) of the osteoclasts remain to be eludicated. Furthermore, the individual effects that these behaviours confer on the shape and extent of the resorption cavity are unclear. In this paper, we develop a lattice-based computational model focused on bone resorption in cortical BMUs to address these questions. Our model takes into account the interaction of osteoclasts with the bone matrix, the interaction of osteoclasts with each other, the production of osteoclasts from the tip of a growing blood vessel, and the renewal of osteoclasts' nuclei by cell fusion. All these features are shown to strongly affect the geometrical prope...

Buenzli, P R; Pivonka, P; Smith, D W; Cummings, P T

2011-01-01

332

Morphological characteristics of frontal sinus and nasal bone focusing on bone resorption and apposition in hypophosphatemic rickets  

DEFF Research Database (Denmark)

To characterize the size and the morphology of the frontal sinus (i.e., structure evolved by bone resorption) and the nasal bone (i.e., structure evolved by bone formation) in adults with hypophosphatemic rickets (HR) compared with controls.

GjØrup, Hans; Kjaer, I

2013-01-01

333

Does increased local bone resorption secondary to breast and prostate cancer result in increased cartilage degradation?  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Breast and prostate cancer patients often develop lesions of locally high bone turnover, when the primary tumor metastasizes to the bone causing an abnormal high bone resorption at this site. The objective of the present study was to determine whether local increased bone turnover in breast and prostate cancer patients is associated with an increase in cartilage degradation and to test in vitro whether osteoclasts or cathepsin K alone generate CTXII from human bone. Methods The study included 132 breast and prostate cancer patient, where presence of bone metastases was graded according to the Soloway score. Total bone resorption (CTXItotal and cartilage degradation (CTXII were determined. Results Breast and prostate cancer patients with bone metastases revealed significant increased levels of CTXItotal at Soloway scores 1 and higher compared to patients without bone metastases (p total significantly decreased at score 3 and 4 (p total, CTXII and CTXII/CTXItotal changed +900%, +130%, and -90%, respectively at Soloway score 4 compared to score 0. The in vitro experiments revealed that osteoclasts released CTXI fragments but not CTXII from bone specimens. The same was observed for cathepsin K. Conclusion Data suggest that an uncoupling between bone resorption and cartilage degradation occurs in breast and lung cancer patient.

Fregerslev Michael

2008-06-01

334

An osteoprotegerin-like peptidomimetic inhibits osteoclastic bone resorption and osteolytic bone disease in myeloma.  

Science.gov (United States)

Multiple myeloma is a B-cell malignancy characterized by the uncontrolled growth of plasma cells in the bone marrow and the development of osteolytic bone disease. Myeloma cells express the receptor activator of nuclear factor kappaB ligand (RANKL), induce RANKL expression in the bone marrow, and down-regulate expression of the decoy receptor osteoprotegerin, thereby promoting bone resorption. Targeting this system in myeloma has clear therapeutic potential. However, osteoprotegerin also binds tumor necrosis factor-related apoptosis inducing ligand (TRAIL) and prevents TRAIL-induced apoptosis of myeloma cells. Whether or not osteoprotegerin can bind TRAIL and prevent apoptosis in vivo and the relative importance of osteoprotegerin binding to TRAIL and RANKL are unclear. In the present study, we have investigated the ability of an osteoprotegerin-like peptidomimetic (OP3-4), designed to block the RANKL/RANK interaction, to inhibit osteoclastic bone resorption and TRAIL-induced apoptosis in vitro and myeloma bone disease in vivo. OP3-4 inhibited osteoclast formation (P bone resorption (P bone surface covered by osteoclasts (P bone area and the development of osteolytic lesions (P bone disease and offer a novel therapeutic approach to treating this aspect of myeloma. [Cancer Res 2007;67(1):202-8]. PMID:17210700

Heath, Deborah J; Vanderkerken, Karin; Cheng, Xin; Gallagher, Orla; Prideaux, Matthew; Murali, Ramachandran; Croucher, Peter I

2007-01-01

335

Effects of initial stresses and time on orthodontic external root resorption.  

Science.gov (United States)

Optimum stresses for a favorable response to orthodontics are still unknown. Here, we compared the effects of initial periodontal ligament (PDL) stresses over time in orthodontic external root resorption (OERR), necrosis, and the TRAP+ cell population. Forty-two rats (Fischer CDF) were treated with 10 cN of force for 5 different time periods. Finite element (FE) models of the first maxillary molars were constructed from ?CT scans to calculate initial PDL stresses. The scans were also used for OERR measurements before histology. Time, stress, and their interaction were significant to result in an OERR increase only in the regions of medium and high stress. OERR was not significantly different between control and treated animals over time in the region of low stress. After 30 days, OERR was increased by 5- and 3-fold in the zone of high- and medium-stress regions, respectively. The TRAP+ cell population initially followed the stress gradient, but changed after bone and necrotic tissue resorption. In the 30-day modeling cycle, the correspondent 3rd principal stress range to promote direct bone resorption and insignificant OERR was between -9.92 and -7.75 KPa. These translate to approximate forces of 30 to 40 cN applied at the bracket level (tipping) of a human maxillary canine. PMID:23442247

Viecilli, R F; Kar-Kuri, M H; Varriale, J; Budiman, A; Janal, M

2013-04-01

336

Nectar resorption in flowers of Sinapis alba L., Brassicaceae and Platanthera chlorantha Custer (Rchb.), Orchidaceae  

International Nuclear Information System (INIS)

Full text: In the flowers of Sinapis alba nectar is secreted by two pairs of nectaries and accumulated as drops between filaments and in the cavity of sepals whereas in Platanthera chlorantha nectar is produced and accumulated within a spur. Previous studies of these species revealed that after a period of secretion and cessation, rapid nectar resorption occurs. The aim of this study was the observation of nectar resorption by the nectaries using radiolabelled sucrose. During the peak of secretion the nectar accumulated in unpollinated flowers was replaced with the same volume of labelled sucrose and after 12-48 hrs of incubation, at the resorption phase, parts of S. alba flowers with nectaries as well as fragments of P. chlorantha spur were sampled and fixed for microautoradiographic studies. In S. alba the presence of [14C(U)] sucrose was detected at the base of nectaries, in phloem elements of main vascular strands supplying glands, whereas both epidermis and nectary parenchyma showed no traces of radiolabelled sugars. In P. chlorantha the presence of labelled sucrose was stated mainly in the walls of nectary cells, which indicate an apoplastic route of reabsorbed nectar. (author)

337

Experimental studies on the resorption and translocation of 14C-aldimorph in selected plant species  

International Nuclear Information System (INIS)

Experimental studies were performed with 14C-labelled 4-n-dodecyl-trans-2,6-dimethyl morpholine and both isolated plant segments and intact seedlings of Hordeum distichon L. and Sinapis alba L. to elucidate resorption and transportation of the fungicidal substance aldimorph. The compound is quickly resorbed by isolated roots and leaves during the initial phase, and accumulated in plant tissue. In the steady state of influx/efflux equilibrium, the root concentration factor amounts to 10 with barley roots and the tissue concentration factor is 3 with mustard cotyledons. The relationship between the resorption of active substance and the concentration of ambient solution was found to be linear, thus corroborating a postulated resorption by diffusion. The morpholine derivative also penetrates into the leaf tissue of intact barley seedlings within few hours and at rather high rates. Nevertheless, according to translocation studies aldimorph has to be considered only moderately mobile. However, metabolites originated in the plant, especially during longer trial periods, show markedly improved translocation properties compared with the mother compound. (author)

338

Resorption of apatite-wollastonite containing glass-ceramic and beta-tricalcium phosphate in vivo.  

Directory of Open Access Journals (Sweden)

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Apatite-wollastonite containing glass ceramic is considered to be difficult to resorb, but we experienced the disappearance of the porous type of Apatite-wollastonite glass ceramic particles . In this study, the resorption of porous apatite-wollastonite glass-ceramic implanted in the femurs of rabbits was investigated, and the process was compared with beta-tricalcium phosphate, a resorbable ceramics. Porous apatite-wollastonite glass-ceramic (70, 80, and 90% porosity and beta-tricalcium phosphate (75% porosity were implanted in the femurs of Japanese white rabbits. Samples were harvested and examined 0, 4, 8, 12, 24 and 36 weeks after implantation. Quantitative analysis of the radiographic and histologic findings was performed with NIH Image software. Radiographic examination demonstrated that the radiopacity and size of the porous apatite-wollastonite glassceramic cylinders decreased gradually after implantation. Histologic examination revealed that the surface area of the apatite-wollastonite glass-ceramic cylinders decreased continuously, and approached 20% of the original area 36 weeks after implantation. However, the resorption rate of porous apatite-wollastonite glass-ceramic was slower than that of beta-tricalcium phosphate. Toluidine blue staining showed abundant new bone formation on the surface of the apatite-wollastonite glassceramic matrix. Considering its mechanical strength, gradual resorption characteristics, and good osteochonductive activity, porous apatite-wollastonite glass-ceramic appears to be a suitable artificial bone substitutes.

Teramoto,Hidefumi

2005-10-01

339

Dioscin inhibits osteoclast differentiation and bone resorption though down-regulating the Akt signaling cascades  

Energy Technology Data Exchange (ETDEWEB)

Highlights: •A natural-derived compound, dioscin, suppresses osteoclast formation and bone resorption. •Dioscin inhibits osteolytic bone loss in vivo. •Dioscin impairs the Akt signaling cascades pathways during osteoclastogenesis. •Dioscin have therapeutic value in treating osteoclast-related diseases. -- Abstract: Bone resorption is the unique function of osteoclasts (OCs) and is critical for both bone homeostasis and pathologic bone diseases including osteoporosis, rheumatoid arthritis and tumor bone metastasis. Thus, searching for natural compounds that may suppress osteoclast formation and/or function is promising for the treatment of osteoclast-related diseases. In this study, we for the first time demonstrated that dioscin suppressed RANKL-mediated osteoclast differentiation and bone resorption in vitro in a dose-dependent manner. The suppressive effect of dioscin is supported by the reduced expression of osteoclast-specific markers. Further molecular analysis revealed that dioscin abrogated AKT phosphorylation, which subsequently impaired RANKL-induced nuclear factor-kappaB (NF-?B) signaling pathway and inhibited NFATc1 transcriptional activity. Moreover, in vivo studies further verified the bone protection activity of dioscin in osteolytic animal model. Together our data demonstrate that dioscin suppressed RANKL-induced osteoclast formation and function through Akt signaling cascades. Therefore, dioscin is a potential natural agent for the treatment of osteoclast-related diseases.

Qu, Xinhua; Zhai, Zanjing; Liu, Xuqiang; Li, Haowei [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Ouyang, Zhengxiao [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Department of Orthopaedics, Hunan Provincial Tumor Hospital and Tumor Hospital of Xiangya School of Medicine, Central South University, Changsha (China); Wu, Chuanlong [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Liu, Guangwang [Department of Orthopaedic Surgery, The Central Hospital of Xuzhou, Affiliated Hospital of Medical Collage of Southeast University, Xuzhou (China); Fan, Qiming; Tang, Tingting [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Qin, An, E-mail: dr.qinan@gmail.com [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Dai, Kerong, E-mail: krdai@163.com [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China)

2014-01-10

340

Dioscin inhibits osteoclast differentiation and bone resorption though down-regulating the Akt signaling cascades  

International Nuclear Information System (INIS)

Highlights: •A natural-derived compound, dioscin, suppresses osteoclast formation and bone resorption. •Dioscin inhibits osteolytic bone loss in vivo. •Dioscin impairs the Akt signaling cascades pathways during osteoclastogenesis. •Dioscin have therapeutic value in treating osteoclast-related diseases. -- Abstract: Bone resorption is the unique function of osteoclasts (OCs) and is critical for both bone homeostasis and pathologic bone diseases including osteoporosis, rheumatoid arthritis and tumor bone metastasis. Thus, searching for natural compounds that may suppress osteoclast formation and/or function is promising for the treatment of osteoclast-related diseases. In this study, we for the first time demonstrated that dioscin suppressed RANKL-mediated osteoclast differentiation and bone resorption in vitro in a dose-dependent manner. The suppressive effect of dioscin is supported by the reduced expression of osteoclast-specific markers. Further molecular analysis revealed that dioscin abrogated AKT phosphorylation, which subsequently impaired RANKL-induced nuclear factor-kappaB (NF-?B) signaling pathway and inhibited NFATc1 transcriptional activity. Moreover, in vivo studies further verified the bone protection activity of dioscin in osteolytic animal model. Together our data demonstrate that dioscin suppressed RANKL-induced osteoclast formation and function through Akt signaling cascades. Therefore, dioscin is a potential natural agent for the treatment of osteoclast-related diseases

 
 
 
 
341

Passive and active in vitro resorption of calcium and magnesium phosphate cements by osteoclastic cells.  

Science.gov (United States)

Biocements are clinically applied materials for bone replacement in non-load-bearing defects. Depending on their final composition, cements can be either resorbed or remain stable at the implantation site. Degradation can occur by two different mechanisms, by simple dissolution (passive) or after osteoclastic bone remodeling (active). This study investigated both the passive and active in vitro resorption behavior of brushite (CaHPO??· 2H?O), monetite (CaHPO?), calcium-deficient hydroxyapatite (CDHA; Ca?(PO?)?HPO?OH), and struvite (MgNH?PO??·?6H?O) cements. Passive resorption was measured by incubating the cement samples in a cell culture medium, whereas active resorption was determined during the surface culture of multinuclear osteoclastic cells derived from RAW 264.7 macrophages. Osteoclast formation was confirmed by showing tartrate resistant acid phosphatase (TRAP) activity on CDHA, brushite, and monetite surfaces, as well as by measuring calcitonin receptor (CT-R) expression as an osteoclast-specific protein by Western blot analysis for struvite ceramics. An absence of passive degradation and only marginally active degradation of cement was the most degradable with a passive (active) release of 9.26 (2.92) Mg²+ ions and a total weight loss of 4.7% over 13 days of the study. PMID:20673025

Grossardt, Christian; Ewald, Andrea; Grover, Liam M; Barralet, Jake E; Gbureck, Uwe

2010-12-01

342

Normal Tempo of Bone Formation in Turner Syndrome despite Signs of Accelerated Bone Resorption  

DEFF Research Database (Denmark)

Aims: To evaluate area bone mineral density (aBMD) and volumetric BMD (vBMD) by dual-energy X-ray absorptiometry, and relations to bone markers and hormones in adolescent women with Turner syndrome (TS). Methods: Cross-sectional study in TS patients (n = 37, 16.7 ± 3.4 years) and control group (n = 49), assessed by dual-energy X-ray absorptiometry, bone markers and hormones. TS patients were divided into a young group receiving ('ongoing') GH (n = 15) and an older group previously receiving ('previous') GH (n = 22). Results: vBMD(spine) was similar in 'ongoing GH' TS, but higher in 'previous GH' TS, compared to controls. vBMD(hip) was lower in 'ongoing GH' TS, but similar in 'previous GH'. z scores for aBMD were uniformly reduced in 'ongoing TS', but near-normalized in 'previous GH' TS. Bone formation and resorption markers were increased in 'ongoing GH' TS, while 'previous GH' TS had elevated bone resorption markers. Conclusion: BMD increased in parallel with age in TS patients receiving optimal estradiol replacement therapy and GH according to consensus guidelines, and in controls. Young TS undergoing pubertal induction and still receiving GH have lower z score BMD than older TS patients receiving hormonal replacement therapy, where a near-normalization of BMD was achieved. TS patients previously receiving GH showed signs of increased bone resorption.

Cleemann, Line; Holm, Kirsten

2011-01-01

343

Risedronate decreases bone resorption and improves low back pain in postmenopausal osteoporosis patients without vertebral fractures.  

Science.gov (United States)

Elderly postmenopausal women who have osteoporosis sometimes experience low back pain, however, the relationship between low back pain and osteoporosis in the absence of vertebral fractures remains unclear. We examined the relationship between bone mineral density (BMD), bone resorption and low back pain in elderly female patients who did not have osteoporotic vertebral fractures. The average BMD was 0.675 g/cm(2) when assessed by dual-energy X-ray absorptiometry (DEXA). Patients were excluded from the study if they had vertebral fractures revealed by radiography, CT scans or MRI. Bisphosphonate (risedronate) was administered for 4 months. The visual analogue scale (VAS) pain score, Roland Morris Disability Questionnaire (RDQ), Short Form-36 (SF-36) questionnaire, BMD and N-terminal telopeptide of type I collagen (NTx; a marker for bone resorption) were examined before and after treatment. DEXA did not increase significantly, but serum and urinary NTx were decreased (-51.4% and -62.0%, respectively) after 4 months of risedronate treatment (p<0.01). The assessment was repeated using the VAS score, RDQ and SF-36, which revealed an improvement after risedronate treatment (p<0.01). A decrease in serum and urinary NTx was associated with improvement of low back pain, suggesting that despite the absence of vertebral fractures, bone resorption due to osteoporosis may cause low back pain. PMID:20044258

Ohtori, Seiji; Akazawa, Tsutomu; Murata, Yasuaki; Kinoshita, Tomoaki; Yamashita, Masaomi; Nakagawa, Koichi; Inoue, Gen; Nakamura, Junichi; Orita, Sumihisa; Ochiai, Nobuyasu; Kishida, Shunji; Takaso, Masashi; Eguchi, Yawara; Yamauchi, Kazuyo; Suzuki, Munetaka; Aoki, Yasuchika; Takahashi, Kazuhisa

2010-02-01

344

Foliar Nitrogen (N, Phosphorus (P Dynamics, and Foliar Resorption of Corylus avellana var. avellana  

Directory of Open Access Journals (Sweden)

Full Text Available Corylus avellana var. avellana (Corylaceae has a widespread distribution in the Central Black Sea Region of Turkey and is very valuable in the food industry and plays an important role in the economy of the Black Sea Region of Turkey. In this study, nitrogen (N and phosphorus (P concentrations along a topographical gradient (from sea level to 550 m and through the growing season (from April to October were investigated. In addition to this, foliar resorption was also studied as resorption efficiency (RE and resorption proficiency (RP which is defined as the proportion of nutrients withdrawn from leaves and the N and P concentrations in senesced leaves, respectively. Statistically significant differences were not found with respect to leaf N concentration and SLA during the growing season although leaf P concentration, leaf N/P ratio and SLA were significantly changed during the growing season. Except for NRE, PRE, ARP, and PRP all of the leaf traits were significantly changed along the topographic gradient. The N/P ratio which is an indicator of N- and P- limitation decreased during the growing season and along the topographic gradient. The N and P concentrations in the senescent leaves of C. avellana was below 50 ?g cm-2 and 3 ?g cm-2, respectively along the topographic gradient and this species is N and P-proficient according to the threshold values. Soil properties along the topographic gradient also changed.

Tugba Bayrak Ozbucak

2011-12-01

345

The estimation of the resorption of radionuclides from the gastro-intestinal tract into blood  

International Nuclear Information System (INIS)

Taking a look at the international literature, resorption rates for the transfer of the following radionuclides from stomach-intestinal tract into the blood have been determined: Cerium, cobalt (also as vitamin B 12), plutonium, ruthenium, strontium and zinc. It was found that the resorption rates determined in experiments and measurements, partly varies by several orders of dimension and are dependent on numerous parameters. A comparison of the measured resorption rates for the single radionuclides with the values based on the recommendations of the radiation protection commission showed that the values used by the radiation protection commission are in many cases too low, partly by several orders of dimension. One may thus conclude that the dose factors given in the fundamental calculation of the radiation protection commission do no longer correspond with the international state of science. In interest of an exact estimation of the radiation burden caused by the nuclear power plant Biblis, we therefore recommend to recheck the further parameters relevant for dose factors and a new calculation of the dose factors within the framework of the model study radioecology Biblis. (orig./MG)

346

Understanding coupling between bone resorption and formation : are reversal cells the missing link?  

DEFF Research Database (Denmark)

Bone remodeling requires bone resorption by osteoclasts, bone formation by osteoblasts, and a poorly investigated reversal phase coupling resorption to formation. Likely players of the reversal phase are the cells recruited into the lacunae vacated by the osteoclasts and presumably preparing these lacunae for bone formation. These cells, called herein reversal cells, cover >80% of the eroded surfaces, but their nature is not identified, and it is not known whether malfunction of these cells may contribute to bone loss in diseases such as postmenopausal osteoporosis. Herein, we combined histomorphometry and IHC on human iliac biopsy specimens, and showed that reversal cells are immunoreactive for factors typically expressed by osteoblasts, but not for monocytic markers. Furthermore, a subpopulation of reversal cells showed several distinctive characteristics suggestive of an arrested physiological status. Their prevalence correlated with decreased trabecular bone volume and osteoid and osteoblast surfaces in postmenopausal osteoporosis. They were, however, virtually absent in primary hyperparathyroidism, in which the transition between bone resorption and formation occurs optimally. Collectively, our observations suggest that arrested reversal cells reflect aborted remodeling cycles that did not progress to the bone formation step. We, therefore, propose that bone loss in postmenopausal osteoporosis does not only result from a failure of the bone formation step, as commonly believed, but also from a failure at the reversal step.

Andersen, Thomas L; Abdelgawad, Mohamed E

2013-01-01

347

Two distinct effects of recombinant human tumor necrosis factor-? on osteoclast development and subsequent resorption of mineralized matrix  

International Nuclear Information System (INIS)

The multifunctional cytokine tumor necrosis factor-? (TNF ?) stimulates osteoclastic resorption. It is not known which steps in osteoclast formation are affected by TNF ?. The authors have investigated the effects of recombinant human TNF ? (rhTNF ?) on osteoclast development and osteoclastic resorption in two different in vitro resorption systems which are each characterized by a different stage of development of the osteoclast. The effects were further compared to those of bovine PTH-(1-84). rhTNF ? at concentrations between 0.01-50 ng/ml (3 x 10(-13) to 1.5 x 10(-9) M) did not alter the activity of mature osteoclasts, measured as 45Ca release in fetal mouse radii. In the osteoclast precursor-dependent system (fetal mouse metacarpals) rhTNF ? had a biphasic effect. It stimulated resorption dose-dependently from 0.01 ng/ml onward, with a maximal response at 0.5 ng/ml. At concentrations above 10 ng/ml rhTNF ?, resorption was inhibited. In experiments in which irradiation was used to block replication, it was found that TNF ? stimulates the proliferation of osteoclast progenitors at both low and high concentrations. As a result, at relatively low concentrations, more osteoclasts were formed in the calcified matrix, coinciding with an increased release of 45Ca. However, at relatively high concentrations, the increase in osteoclast progenitors did not lead to increased resorption, since the putative osteoclast progenitors were arrested in the periosteum. In comprested in the periosteum. In comparison, bovine PTH-(1-84) stimulated resorption independent of proliferation by enhancing the differentiation of postmitotic osteoclast precursors and activating mature osteoclasts. In conclusion, the effects of TNF ? on osteoclastic resorption are dependent on the stage of osteoclast development and the concentrations applied

348

A Comparison of Apical Root Resorption in Incisors after Fixed Orthodontic Treatment with Standard Edgewise and Straight Wire (MBT Method  

Directory of Open Access Journals (Sweden)

Full Text Available Statement of Problem: One of the major outcomes of orthodontic treatment is the apical root resorption of teeth moved during the treatment. Identifying the possible risk factors, are necessary for every orthodontist. Purpose: The aim of this study was to compare the rate of apical root resorption after fixed orthodontic treatment with standard edgewise and straight wire (MBT method, and also to evaluate other factors effecting the rate of root resorption in orthodontic treatments.Materials and Method: In this study, parallel periapical radiographs of 127 patients imaging a total of 737 individual teeth, were collected. A total of 76 patients were treated by standard edgewise and 51 patients by straight wire method. The periapical radiographs were scanned and then the percentage of root resorption was calculated by Photoshop software. The data were analyzed by Paired-Samples t-test and the Generalized Linear Model adopting the SPSS 15.0.Results: In patients treated with straight wire method (MBT, mean root resorption was 18.26% compared to 14.82% in patients treated with standard edgewise tech-nique (p< .05. Male patients had higher rate of root resorption,statistically significant (p< .05. Age at onset of treatment, duration of treatment, type of dental occlusion, premolar extractions and the use of intermaxillary elastics had no significant effect on the root resorption in this study.Conclusion: Having more root resorption in the straight wire method and less in the standard edgewise technique can be attributed to more root movement in pre-adjusted MBT technique due to the brackets employed in this method.

Zahed Zahedani SM.

2013-09-01

349

Ridge 2000 Data Management System  

Science.gov (United States)

Hosted at Lamont by the marine geoscience Data Management group, mgDMS, the NSF-funded Ridge 2000 electronic database, http://www.marine-geo.org/ridge2000/, is a key component of the Ridge 2000 multi-disciplinary program. The database covers each of the three Ridge 2000 Integrated Study Sites: Endeavour Segment, Lau Basin, and 8-11N Segment. It promotes the sharing of information to the broader community, facilitates integration of the suite of information collected at each study site, and enables comparisons between sites. The Ridge 2000 data system provides easy web access to a relational database that is built around a catalogue of cruise metadata. Any web browser can be used to perform a versatile text-based search which returns basic cruise and submersible dive information, sample and data inventories, navigation, and other relevant metadata such as shipboard personnel and links to NSF program awards. In addition, non-proprietary data files, images, and derived products which are hosted locally or in national repositories, as well as science and technical reports, can be freely downloaded. On the Ridge 2000 database page, our Data Link allows users to search the database using a broad range of parameters including data type, cruise ID, chief scientist, geographical location. The first Ridge 2000 field programs sailed in 2004 and, in addition to numerous data sets collected prior to the Ridge 2000 program, the database currently contains information on fifteen Ridge 2000-funded cruises and almost sixty Alvin dives. Track lines can be viewed using a recently- implemented Web Map Service button labelled Map View. The Ridge 2000 database is fully integrated with databases hosted by the mgDMS group for MARGINS and the Antarctic multibeam and seismic reflection data initiatives. Links are provided to partner databases including PetDB, SIOExplorer, and the ODP Janus system. Improved inter-operability with existing and new partner repositories continues to be strengthened. One major effort involves the gradual unification of the metadata across these partner databases. Standardised electronic metadata forms that can be filled in at sea are available from our web site. Interactive map-based exploration and visualisation of the Ridge 2000 database is provided by GeoMapApp, a freely-available Java(tm) application being developed within the mgDMS group. GeoMapApp includes high-resolution bathymetric grids for the 8-11N EPR segment and allows customised maps and grids for any of the Ridge 2000 ISS to be created. Vent and instrument locations can be plotted and saved as images, and Alvin dive photos are also available.

Goodwillie, A. M.; Carbotte, S. M.; Arko, R. A.; Haxby, W. F.; Ryan, W. B.; Chayes, D. N.; Lehnert, K. A.; Shank, T. M.

2005-12-01

350

Alveolar osseous defect in rat for cell therapy: preliminary report / Defeito ósseo alveolar em ratos para terapia celular: estudo preliminar  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: Reproduzir um novo modelo de defeito ósseo alveolar em ratos Wistar que será utilizado para terapia genética e estudos com células tronco. Adicionalmente, outro objetivo do presente estudo foi determinar o pico de regeneração óssea do defeito criado na região alveolar do modelo experimenta [...] l. MÉTODOS: Os animais foram aleatoriamente divididos em dois grupos de sete animais. Através de uma incisão gengivobucal foi criado um defeito ósseo medindo 28 mm² de área na região alveolar dos ratos. Os ratos foram sacrificados após duas semanas (n=7) e quatro semanas (n=7) da cirurgia. RESULTADOS: A área média do defeito alveolar após duas semanas de cirurgia foi de 22.27 ± 1.31 mm² e a área média do defeito alveolar após quatro semanas de cirurgia foi de 9.03 ± 1.17 mm². A taxa de formação óssea foi de 5.73 ± 1.31 mm² após duas semanas de cirurgia e de 19 ± 1.17 mm² após quatro semanas de cirurgia. Foi observada diferença estatisticamente significante na taxa de formação óssea entre o grupo dos animais sacrificados com duas e quatro semanas (p=0.003). CONCLUSÃO: Este estudo demonstrou que a maior taxa de regeneração óssea ocorreu no período entre duas e quatro semanas após a cirurgia de criação do defeito ósseo alveolar, portanto esta observação sugere que o período de tempo de quatro semanas será suficiente para avaliar a capacidade de células tronco em regenerar osso em ratos Wistar com defeito ósseo alveolar. Abstract in english PURPOSE: To study were to reproduce an alveolar bone defect model in Wistar rats to be used for testing the efficacy of stem cell therapies. Additionally, we also aimed to determine the osteogenesis process of this osseous defect in the 1 month period post-surgery. METHODS: The animals were randomly [...] divided into two groups of 7 animals each. A gingivobuccal incision was made, and a bone defect of 28 mm² of area was performed in the alveolar region. Animals were killed at 2 weeks after surgery (n=7) and 4 weeks after surgery (n=7). RESULTS: The average area of the alveolar defect at time point of 2 weeks was 22.27 ± 1.31 mm² and the average area of alveolar defect at time point of 4 weeks was 9.03 ± 1.17 mm². The average amount of bone formation at time point of 2 weeks was 5.73 ± 1.31 mm² and the average amount of bone formation at time point of 4 weeks was 19 ± 1.17 mm². Statistically significant differences between the amount of bone formation at 2 weeks and 4 weeks after surgery were seen (p=0.003). CONCLUSION: The highest rate of ossification occurred mostly from 2 to 4 weeks after surgery. This observation suggests that 4 weeks after the bone defect creation should be a satisfactory timing to assess the potential of bone inductive stem cells to accelerate bone regeneration in Wistar rats.

Cassio Eduardo, Raposo-Amaral; Gerson Shigeru, Kobayashi; Ana Beatriz, Almeida; Daniela F., Bueno; Fatima Rodrigues de Souza e, Freitas; Luiz Carlos, Vulcano; Maria Rita, Passos-Bueno; Nivaldo, Alonso.

2010-08-01

351

Alveolar haemorrhage in eosinophilic granulomatosis and polyangiitis (Churg-Strauss).  

Science.gov (United States)

We describe two patients of alveolar haemorrhage in patients with eosinophilic granulomatosis with polyangiitis (eGPA). This report adds to the evidence that pulmonary haemorrhage is a rare but severe manifestation of eGPA. It may not be associated with positive ANCA antibodies and requires aggressive treatment. PMID:24464436

Jagadeesh, L Yalakki; Sangle, S R; Verma, H; D'Cruz, D

2014-08-01

352

Alveolar occupation infiltrations, eosinophilia in peripheral blood and bronchoalveolar lavage  

International Nuclear Information System (INIS)

A case of a patient of 25 years old is shown with the antecedent of no potable water consumption who entered for having pulmonary symptoms, fever, presence of alveolar occupation infiltrations and eosinophilia in peripheral blood treatment with antiparasitary started with a significant improvement of the symptoms, infiltrations and eosinophilia. It is considered eosinophilic pneumonia diagnostic by parasitary infection (Loefffers Syndrome)

353

Development, maturation, and aging of the alveolar bone. New insights.  

Science.gov (United States)

Osteoblasts and bone tissue of the mandibular and maxillary alveolar processes substantially differ from osteoblasts and bone in other parts of the skeleton. These differences are apparent during embryonic development, maturation, and aging of these bones. The cellular and molecular basis for these differences is still not clear, but it is unfolding at record speed. PMID:9023059

Zernik, J H; Nowroozi, N; Liu, Y H; Maxson, R

1997-01-01

354

Is there correlation between alveolar and systemic bone density?  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: avaliar a correlação entre a densidade óssea alveolar maxilomandibular e a densidade mineral óssea sistêmica. MÉTODOS: a absorciometria duoenergética por raios X do osso alveolar maxilomandibular (região anterior e posterior), dos sítios sistêmicos padrões (coluna lombar e fêmur) e da terc [...] eira vértebra cervical foi realizada em 23 mulheres de meia idade. Radiografias periapicais dos incisivos superiores também foram obtidas com uma escala de alumínio como referência para a leitura digital da densidade óssea da região apical. RESULTADOS: o teste de correlação de Spearman revelou que a densidade da região apical foi correlacionada com a do colo femoral (r = 0,433; p Abstract in english OBJECTIVE: The present study assessed the correlation between maxillomandibular alveolar bone density and systemic bone mineral density (BMD). METHODS: Dual-energy X-ray absorptiometry of the anterior and posterior maxillomandibular alveolar bone, of the standard sites for the measurement of BMD (lu [...] mbar spine and femur) and the third cervical vertebra was performed on 23 middle-aged women. Periapical radiographs were also obtained, with an aluminum step-wedge as reference for the digital reading of apical bone density of the upper incisors. RESULTS: Spearman's correlations coefficients revealed that density in the apical region was correlated with that of the femoral neck (r = 0.433; p

Paula Cabrini, Scheibel; Adilson Luiz, Ramos; Lilian Cristina Vessoni, Iwaki.

355

Reconstruction of alveolar cleft with allogenous bone graft: clinical considerations  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese INTRODUÇÃO: o enxerto ósseo secundário consiste em um procedimento rotineiro no tratamento de pacientes com fissura alveolar. Via de regra, é realizado no final da dentadura mista, na época de erupção do canino permanente, com osso medular autógeno retirado da crista ilíaca. OBJETIVO: o presente art [...] igo discorre sobre a alternativa de enxerto ósseo autógeno realizado com osso alógeno, obtido de banco de ossos humanos, ilustrando o resultado com a apresentação de um caso clínico de fissura alveolar unilateral do lado esquerdo. Abstract in english INTRODUCTION: Secondary bone grafting consists in a routine procedure on the treatment of patients with alveolar cleft. Usually, it is performed by the end of the mixed dentition, when the permanent canine is erupting, with autogenous cancellous bone from the iliac crest. OBJECTIVE: The present arti [...] cle discusses the alternative of autogenous bone grafting with allogeneic bone, obtained from human bone bank, illustrating the result with the presentation of a clinical case of left unilateral alveolar cleft.

Omar Gabriel da, Silva Filho; Terumi Okada, Ozawa; Cláudia, Bachega; Marco Aurélio, Bachega.

2013-12-01

356

EVALUATION OF TRACE-ELEMENT INTERACTIONS USING CULTURED ALVEOLAR MACROPHAGES  

Science.gov (United States)

It is important to consider the interactions of toxic trace elements in an evaluation of the toxicity of environmental pollutants. The in vitro toxicity screening system, using the rabbit alveolar macrophage, provides a particularly useful system for evaluating trace-element inte...

357

Effects of Nonsurgical Periodontal Treatment on the Alveolar Bone Density  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo desse estudo foi avaliar os efeitos do tratamento periodontal não cirúrgico na densidade do osso alveolar e na altura óssea alveolar usando radiografias digitais diretas. Dezenove pacientes (média de idade 36±7,3 anos) com pacientes com periodontite crônica generalizada foram examinados n [...] o tempo 0 e aos 90 (90AT) e 180 (180AT) dias após o tratamento periodontal não cirúrgico. Dois grupos de sítios foram radiografados, 39 com profundidade de bolsa a sondagem (PBS)?3 mm e nível de inserção clínica (NIC)?1 mm (sítios rasos) e 62 com PBS?5 mm and NIC?3 mm (sítios profundos). A densidade foi avaliada considerando as regiões ósseas de interesse na crista óssea alveolar (ROI I) e no osso medular (ROI II). A altura óssea compreendia a distância entre a crista óssea alveolar e a junção cemento-esmalte. Os sítios profundos mostraram um significante aumento na densidade óssea na ROI I tendo p Abstract in english The aim of this study was to evaluate the effects of nonsurgical periodontal treatment on alveolar bone density (ABD) and bone height (BH) using direct digital radiography. Nineteen patients (mean age: 36±7.3 years) with generalized chronic periodontitis were examined at baseline, 90 (90AT) and 180 [...] (180AT) days after nonsurgical periodontal therapy. Radiographs were taken from two sites with specific characteristics: 39 sites with probing pocket depth (PPD)?3 mm and clinical attachment level (CAL)?1 mm (shallow sites); and 62 sites with PPD?5 mm and CAL?3 mm (deep sites). The ABD was assessed considering the bone regions of interest at the alveolar bone crest (ROI I) and at the medullar bone (ROI II). The BH was assessed considering the distance from the alveolar bone crest to the cementoenamel junction. Mann-Whitney test was used for the overall demographic data, Wilcoxon test was used to compare the baseline, 90AT and 180AT data as well as to compare the groups and subgroups within the same evaluation period. The significance level was set at 5%. The deep sites showed a significant increase of ABD in ROI I at 90AT (p

Fabiana Cervo de, Barros; Flávia Farah, Braga; Ricardo Guimarães, Fischer; Carlos Marcelo da Silva, Figueredo.

2014-04-01

358

Role of carbonic anhydrase in bone resorption induced by 1,25 dihydroxyvitamin D3 in vitro  

Science.gov (United States)

The calvaria of 5-to-6-day-old mice treated with 1 x 10 to the -8th M of 1,25(OH)2D3 in vitro for 48 hours are examined in order to study the function of carbonic anhydrase in bone resorption. Calcium concentrations in the culture were measured to assess bone resorption. It is observed that 1,25(OH)2D3 effectively stimulates bone resorption in vitro and the resorption is dose-dependent. The effects of azetazolamide on 1,25(OH)2D3-induced bone resorption are investigated. The data reveal that 1,25(OH)2D3-induced calcium release is associated with an increase in the carbonic anhydrase activity of bone, and bone alkaline phosphatase activity is decreased and acid phosphatase activity is increased in response to 1,25(OH)2D3. A two-fold mechanism for 1,25(OH)2D3-induced bone resorption is proposed; the first mechanism is an indirect activation of osteoclasts and the second involves an interaction between hormone and osteoclast precursors.

Hall, G. E.; Kenny, A. D.

1985-01-01

359

Mobilization of the inferior alveolar nerve with simultaneous implant insertion: a new technique. Case report.  

Science.gov (United States)

For reconstruction of an atrophied posterior mandible, different therapeutic options have been proposed, such as autologous bone grafting, guided bone regeneration for vertical ridge augmentation, and inferior alveolar nerve (IAN) mobilization with simultaneous implant placement. The possible dehiscence of soft tissues covering the surgical zone makes the first and second techniques unpredictable. Moreover, two surgical sites are necessary and a long treatment time is required (about 12 months). With IAN mobilization, only one surgical intervention is required and the total treatment time is shorter (about 6 months). However, this technique risks irreversible damage to the IAN, with consequent functional alterations. Current studies have shown extreme variability in the examination of functionality of the neurovascular bundle after its mobilization. This variability can be attributed both to the methodology used for the tests, which evoke subjective answers from the patient, and to the surgical procedure, which is highly dependent on operator technique. Nerve damage can be the result of an overstretched mucoperiosteal flap in the premolar area to achieve optimal visibility of the surgical zone. This article reports a case in which a new surgical approach to IAN mobilization is performed using a specifically engineered device for simplified bone surgery (Mectron Piezosurgery). This device enables the surgeon to cut hard tissue without injuring the soft tissues. Therefore, there is a lower risk of damaging the IAN, and it is possible to reduce overstretching of the mental nerve by creating a smaller bone window and using an apicocoronal inclination of instruments to capture the neurovascular bundle. PMID:16089045

Bovi, Mauro

2005-08-01

360

The role of time and pressure on alveolar recruitment  

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Inappropriate mechanical ventilation in patients with acute respiratory distress syndrome can lead to ventilator-induced lung injury (VILI) and increase the morbidity and mortality. Reopening collapsed lung units may significantly reduce VILI, but the mechanisms governing lung recruitment are unclear. We thus investigated the dynamics of lung recruitment at the alveolar level. Rats (n = 6) were anesthetized and mechanically ventilated. The lungs were then lavaged with saline to simulate acute respiratory distress syndrome (ARDS). A left thoracotomy was performed, and an in vivo microscope was placed on the lung surface. The lung was recruited to three recruitment pressures (RP) of 20, 30, or 40 cmH2O for 40 s while subpleural alveoli were continuously filmed. Following measurement of microscopic alveolar recruitment, the lungs were excised, and macroscopic gross lung recruitment was digitally filmed. Recruitment was quantified by computer image analysis, and data were interpreted using a mathematical model. The majority of alveolar recruitment (78.3 ± 7.4 and 84.6 ± 5.1%) occurred in the first 2 s (T2) following application of RP 30 and 40, respectively. Only 51.9 ± 5.4% of the microscopic field was recruited by T2 with RP 20. There was limited recruitment from T2 to T40 at all RPs. The majority of gross lung recruitment also occurred by T2 with gradual recruitment to T40. The data were accurately predicted by a mathematical model incorporating the effects of both pressure and time. Alveolar recruitment is determined by the magnitude of recruiting pressure and length of time pressure is applied, a concept supported by our mathematical model. Such a temporal dependence of alveolar recruitment needs to be considered when recruitment maneuvers for clinical application are designed. PMID:19074576

Albert, Scott P.; DiRocco, Joseph; Allen, Gilman B.; Bates, Jason H. T.; Lafollette, Ryan; Kubiak, Brian D.; Fischer, John; Maroney, Sean; Nieman, Gary F.

2009-01-01

 
 
 
 
361

Mantle flow and melting beneath oceanic ridge ridge ridge triple junctions  

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Plate boundary geometry likely has an important influence on crustal production at mid-ocean ridges. Many studies have explored the effects of geometrical features such as transform offsets and oblique ridge segments on mantle flow and melting. This study investigates how triple junction (TJ) geometry may influence mantle dynamics. An earlier study [Georgen, J.E., Lin, J., 2002. Three-dimensional passive flow and temperature structure beneath oceanic ridge-ridge-ridge triple junctions. Earth Planet. Sci. Lett. 204, 115-132.] suggested that the effects of a ridge-ridge-ridge configuration are most pronounced under the branch with the slowest spreading rate. Thus, we create a three-dimensional, finite element, variable viscosity model that focuses on the slowest-diverging ridge of a triple junction with geometry similar to the Rodrigues TJ. This spreading axis may be considered to be analogous to the Southwest Indian Ridge. Within 100 km of the TJ, temperatures at depths within the partial melting zone and crustal thickness are predicted to increase by ~ 40 °C and 1 km, respectively. We also investigate the effects of differential motion of the TJ with respect to the underlying mantle, by imposing bottom model boundary conditions replicating (a) absolute plate motion and (b) a three-dimensional solution for plate-driven and density-driven asthenospheric flow in the African region. Neither of these basal boundary conditions significantly affects the model solutions, suggesting that the system is dominated by the divergence of the surface places. Finally, we explore how varying spreading rate magnitudes affects TJ geodynamics. When ridge divergence rates are all relatively slow (i.e., with plate kinematics similar to the Azores TJ), significant along-axis increases in mantle temperature and crustal thickness are calculated. At depths within the partial melting zone, temperatures are predicted to increase by ~ 150 °C, similar to the excess temperatures associated with mantle plumes. Likewise, crustal thickness is calculated to increase by approximately 6 km over the 200 km of ridge closest to the TJ. These results could imply that some component of the excess volcanism observed in geologic settings such as the Terceira Rift may be attributed to the effects of TJ geometry, although the important influence of features like nearby hotspots (e.g., the Azores hotspot) cannot be evaluated without additional numerical modeling.

Georgen, Jennifer E.

2008-06-01