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ABSTRACT: New biomaterials including surface modifications should undergo in vitro and in vivo evaluation before clinical trials. The objective of our in vivo study was to evaluate the biocompatibility of one of the newly fabricated zirconia implant surfaces, called "mds". For this purpose, the osseointegration of these implants was analyzed after implantation in surgically created defects in the cranium of adult male rats. After a healing period of 28 and 56 days, respectively, bone tissue specimens containing the implants were processed and histologically analyzed. For this purpose, sections were stained with haematoxylin/eosin and Masson Goldner trichrome. No signs of cellular inflammatory infiltrate were found in any of the animals. After 28 days, slices showed pronounced development of blood vessels and bone regeneration. After 56 days of healing, direct bridging of the bone defects was detectable with distinctly visible kit lines. There were cell rich areas of connective tissue/bone marrow between zirconia discs and bearing bone. Histomorphometric analysis presented a regenerated bone mean value of 36.3% after 28 days of healing. After 56 days of healing, a 1.6 fold increased bone mean value was observed (58.2%). Using the same analysis, 1% and 39.9% of bone-implant-contact was visible after both healing periods, respectively. On average, connective tissue/marrow spaces occupied 99% of implant-contact-area after 28 days of healing. This area was reduced to 60.1% after 56 days. Within the limits of the animal investigation presented, it was concluded that the tested surface modification of zirconia implants were biocompatible and osseoconductive.
Annals of anatomy = Anatomischer Anzeiger: official organ of the Anatomische Gesellschaft 10/2012; · 0.88 Impact Factor
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ABSTRACT: The treatment of mucogingival problems is one of the main objectives of periodontal treatment. The insufficient or absent gingival attachment increases the risk of development of gingival recessions. Multiple gingival augmentation techniques of varying level of success are known. The aim of this study has been to clinically and histologically evaluate the integration process of scaffolds composed of primary human fibroblasts derived from keratinized gingiva on collagenous carriers. Ten patients exhibiting a mucogingival problem and gingival inflammation of the related teeth were included in the study. In total, 34 teeth in the anterior part of the maxilla and the mandible underwent treatment. Clinically, over a 6 month period of observation, a significant decrease in the distance from cemento-enamel junction to mucogingival junction (CEJ-MGJ) was revealed. Histologically, mature connective tissue covered by keratinized epithelium was found after 12 weeks. No specimens revealed an inflammatory response. A complete clinical healing was observed after 2 weeks in eight patients [early healing index (EHI)=I]. The results of clinical evaluation indicate that the method of primary culture of human fibroblasts on a collagenous carrier for gingival augmentation is an esthetic and effective method of mucogingival complex repair. The scaffolds were substituted and completely re-epithelialized within 12 weeks according to histologic results.
Annals of anatomy = Anatomischer Anzeiger: official organ of the Anatomische Gesellschaft 05/2012; · 0.88 Impact Factor
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ABSTRACT: The aim of this study was to examine the effects of BONITmatrix(®) and OSSA NOVA bone graft materials on osteogenic differentiation. For this, mRNA expression of Alpl, Acp5, Bglap, Phex and Runx2 was analysed using quantitative RT-PCR in surgically created defects to the cranium of adult male rats. Cranial samples were collected after implantation of BONITmatrix(®) or OSSA NOVA scaffolds into these defects for 4 weeks and gene expressions of Alpl, Acp5, Bglap, Phex and Runx2 were measured by quantitative RT-PCR. Real-time PCR analyses showed significantly higher expressions of Acp5, Alpl and Bglap only in the group treated with BONITmatrix(®) compared to untreated controls. No changes in transcript expression of Phex and Runx2 were detectable between the analysed groups. Furthermore, in rats treated with OSSA NOVA the same transcript level of all tested genes was detected as shown in controls. In conclusion, it can be stated that only the granular dosage form of BONITmatrix(®) is able to stimulate osteoblast differentiation, whereas OSSA NOVA has no influence on the gene expression of osteoblasts.
Annals of anatomy = Anatomischer Anzeiger: official organ of the Anatomische Gesellschaft 04/2012; · 0.88 Impact Factor
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ABSTRACT: Natural fibers have long been used in several branches of industry. Nowadays, they are considered as composite materials in medicine with special focus on artificial tissue scaffolding, drug-release systems, cardiovascular patches and nerve cuffs. The purpose of this study has been to examine the in vitro biocompatibility of newly designed "green composites". Therefore, composites containing flax fibers from transgenic flax plants producing polyhydroxybutyrate (M50) and control (wt-NIKE) plants in a polylactid (PLA) or polycaprolactone (PCL) matrix were prepared and mice fibroblast viability and cytotoxicity determined after incubation for 12-48h and 3 weeks with those composites. After 24h and 48h, all green composites have a strong influence on cell viability and membrane stability without any differences among each other. The cell viability of treated cells is approximately 82.5-93% of those of untreated control cells, respectively. The increase in cytotoxicity ranged between 1.4 and 2.9 fold compared to untreated cells. After 3 weeks of incubation, no significant changes were detectable in the amount of dead and living cells between composite treated and untreated cells. In conclusion, the tested new "green composites" showed a good biocompatibility. The biocompatibility of composites from transgenic flax plant fibers producing PHB did not differ from composites of non-transgenic flax plant fibers.
Annals of anatomy = Anatomischer Anzeiger: official organ of the Anatomische Gesellschaft 02/2012; · 0.88 Impact Factor
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ABSTRACT: The activity of cytoskeletal proteins like talin, vinculin and nestin increases in muscle that regenerates. Little is known about their role or at least their expression in the process of regeneration in masticatory muscles of mdx mice, a model of Duchenne muscular dystrophy. To determine a potential role of cytoskeletal proteins in the regeneration process of mdx masticatory muscles, we examined the expression of talin 1, talin 2, vinculin and nestin in 100-day-old control and mdx mice using quantitative RT-PCR, Western blot analyses and histochemistry. The protein expression of talin 1, talin 2, nestin and vinculin in mdx muscles remained unchanged as compared with normal mice. However, in mdx masseter it was found a relative increase of nestin compared to controls. The protein expression of talin 1 and vinculin tended to be increased in mdx tongue and talin 2 to diminish in mdx masseter and temporal muscle. In mdx mice, we found significantly lower percentage of transcripts coding for nestin, talin 1, talin 2 and vinculin in masseter (p < 0.05) and temporal muscle (p < 0.001). In contrast, the mRNA expression of nestin was found to be increased in mdx tongue. Activated satellite cells, myoblasts and immature regenerated muscle fibres in mdx masseter and temporal revealed positive staining for nestin. The findings of the presented work suggest dystrophin-lack-associated changes in the expression of cytoskeletal proteins in mdx masticatory muscles could be compensatory for dystrophin absence. The expression of nestin may serve as an indicator for the regeneration in the orofacial muscles.
Archivum Immunologiae et Therapiae Experimentalis 02/2012; 60(2):137-43. · 2.54 Impact Factor
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ABSTRACT: Abstract To improve osseointegration, different possible dental implant surface modifications, e.g., alterations of surface chemistry and roughness, have been developed. The purpose of this study was to examine the in vitro biocompatibility of newly designed zirconium implants with different surface modifications in comparison with commercially available zirconium and titanium implants. Therefore, cell viability and proliferation were measured after 21 days and correlated with surface structures. In the presence of new ceramic implants with an "mds (blasted/etched)" and a "blasted" surface, cell viability was 1.29- and 1.26-fold increased, respectively, compared to untreated cells, whereas cell viability was unchanged in the presence of reference implants and new ceramic implants with an "etched" surface. The cell viability findings correlate with the results of the cell cytotoxicity assay. The etched implants showed a surface with high roughness and heterogeneity, whereas the mds and blasted implants showed a similar, very rough-textured homogenate surface. The in vitro biocompatibility of two new ceramic implants was significantly better in comparison with the tested reference ceramic and titanium implants. The good biocompatibility may be attributed to the homogenous surface of these implants, and these surfaces might hasten osseointegration.
Biomedizinische Technik/Biomedical Engineering 01/2012; 57(1):11-5. · 0.53 Impact Factor
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ABSTRACT: Abstract One of the conditions for ensuring success in implant surgery with an immediate loading (IL) protocol is to achieve maximum primary stability (PS) through the use of dental implants with the appropriate design and surface and a properly prepared osseous bed. The aim of this study was to assess the stability, degree of osseointegration, and success rate after inserting an implant with IL in an osseous bed prepared with burs or an ultrasonic device. Twenty-five patients requiring single tooth replacement (tioLogic; Dentaurum, Ispringen, Germany) in the aesthetic zone were divided randomly into the test (K0) and control (K1) groups. The following factors were investigated: primary (PS-ISQ) and secondary (SS-ISQ) stability- implant stability quotient (ISQ value) by Ostell Mentor, initial width of the alveolar ridge, marginal bone loss (MBL), and buccal bone thickness. The effectiveness of the implant treatment 1 year after the surgery was 100% for group K0 and 93.3% for group K1. A significant correlation was observed between PS and MBL after 1 month. No statistically significant differences were noted between the groups with regard to MBL after 6 months (K0 0.5±0.4 mm vs. K1 0.8±1.3 mm), PS-ISQ (K0 70±4 vs. K1 71±4), and SS-ISQ (K0 70±2 vs. K1 72±3). The average ISQ value of 70±4 is sufficient to allow for IL. A high level of PS results in lower MBL.
Biomedizinische Technik/Biomedical Engineering 01/2012; 57(1):3-9. · 0.53 Impact Factor
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ABSTRACT: Abstract The modification of flax fibers to create biologically active dressings is of undoubted scientific and practical interest. Flax fibers, derived from transgenic flax expressing three bacterial genes for the synthesis of poly-3-hydroxybutyric acid (PHB), have better mechanical properties than unmodified flax fibers; do not show any inflammation response after subcutaneous insertion; and have a good in vitro and in vivo biocompatibility. The aim of this study was to examine the applicability of composites containing flax fibers of genetically modified (M50) or non-modified (wt-Nike) flax within a polylactide (PLA) matrix for bone regeneration. For this, the mRNA expression of genes coding for growth factors (insulin-like growth factor IGF1, IGF2, vascular endothelial growth factor), for osteogenic differentiation (alkaline phosphatase, osteocalcin, Runx2, Phex, type 1 and type 2 collagen), and for bone resorption markers [matrix metalloproteinase 8 (MMP8), acid phosphatase type 5] were analyzed using quantitative real-time polymerase chain reaction. We found a significant elevated mRNA expression of IGF1 with PLA and PLA-wt-Nike composites. The mRNA amount of MMP8 and osteocalcin was significantly decreased in all biocomposite-treated cranial tissue samples compared to controls, whereas the expression of all other tested transcripts did not show any differences. It is assumed that both flax composites are able to stimulate bone regeneration, but composites from transgenic flax plants producing PHB showed faster bone regeneration than composites of non-transgenic flax plants. The application of these linen membranes for bone tissue engineering should be proved in further studies.
Biomedizinische Technik/Biomedical Engineering 01/2012; 57(1):53-8. · 0.53 Impact Factor
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ABSTRACT: Abstract Objective: To determine the lingual surface morphology of central and lateral upper incisors evaluating constant morphological regions for better adhesion of industrial prefabricated lingual brackets. Material and methods: A total of 102 randomly selected patients at the end of the first phase of second dentition with intact central and lateral upper incisors participated in this study. After impression taking and cast model preparation, 3D laser scans of the lingual surface of the upper central and lateral incisors were taken (Laserscan 3D®, Willytec, Munich, Germany), digitalised, and transferred into CAD software to analyse the surface morphology by superimposition. For better comparison of morphological variations and determination of the most constant lingual regions, the surface was divided into five parts: incisal edge, mesial ridge, lateral ridge, cingulum, and medial sector. Statistical analysis was performed by the paired t-test. Results: Statistically significant differences were found in all surfaces, with cingulum as the most inconstant region. The most constant region was the medial sector and the mesial ridge. Conclusion: As expected, the lingual surface underlies a high intra-individual variation complicating industrial prefabricated lingual brackets adhesion. However, the mesial ridge and the medial sector seem to be the most constant regions within intra-individual morphological variations.
Biomedizinische Technik/Biomedical Engineering 01/2012; 57(1):71-7. · 0.53 Impact Factor
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ABSTRACT: Adaptive remodelling of the mandibular condyle in response to mandibular advancement is the mechanism exploited by orthodontic forward displacement devices.
This work investigated the expression of collagens, matrix metalloproteinases and vascular endothelial growth factor during this process.
Twenty juvenile pigs were randomly divided into two experimental groups, where the treatment group was fitted with mandibular advancement splints, and the control group was not. Changes in the mRNA content of condylar cartilage tissue was then were measured by real-time PCR using specific primers after 4weeks of treatment.
The temporal pattern of the expression of Col1 and MMP13 during condylar adaptation coincided with that during natural condylar growth. The amount of the expression of Col10 during condylar adaptation was significantly lower (p<0.05), whereas the expression of Col2, MMP8 and VEGF was significantly higher compared to natural growth (p<0.05).
It is suggested that condylar adaptation in growing pigs triggered by mandibular forward positioning results not only from passive adaptation of cartilage, but also involves growth affected processes. Our results showed that mechanical strain produced by mandibular advancement induced remodelling and revascularization in the posteriocranial mandibular condyle. These results are mostly consistent with former published histological and histomorphometrical analyses.
Archives of oral biology 10/2011; 57(6):594-8. · 1.65 Impact Factor
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ABSTRACT: The aim of this study was to investigate the effects of BONITmatrix(®) and OSSA NOVA on the expression of growth factors and osteogenic differentiation. For this purpose, the mRNA expression of VEGF, IGF1, IGF2, collagen-1, collagen-2 and MMP8 was analysed in surgically created defects on the crania of adult male rats. Cranial samples were collected after implantation of BONITmatrix(®) or OSSA NOVA scaffolds for 4 weeks and determinations of gene expression were performed by quantitative RT-PCR. Real-time RT-PCR analyses showed a significantly higher expression of IGF1 in both groups treated with BONITmatrix(®) and OSSA NOVA compared to untreated controls, whereas type I collagen mRNA expression only increased in BONITmatrix(®) treated rats compared to controls. No changes in transcript expression of IGF2, VEGF, collagen-2 and MMP8 were detectable between the analysed groups. In conclusion, BONITmatrix(®) and OSSA NOVA stimulate the expression of growth factor IGF1, but only the granular dosage form is able to stimulate osteoblast differentiation.
Annals of anatomy = Anatomischer Anzeiger: official organ of the Anatomische Gesellschaft 10/2011; 194(2):179-84. · 0.88 Impact Factor
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09/2011; , ISBN: 978-953-307-481-8
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ABSTRACT: It has been suggested that increased oxidative stress and the glutathione antioxidant system play an important role in the pathogenesis of Duchenne muscular dystrophy. However, there is still a lack of data about the oxidative status in dystrophic masticatory muscles.
In the masticatory muscles of the mouse model of Duchenne muscular dystrophy (mdx and controls; 100 days old, n=8-10 each group) we examined the GSH and GSSG content (glutathione reduced/oxidized form) and the level of lipid peroxidation (LPO) as measured by the thiobarbituric acid-reaction.
In the mdx mice masticatory muscles we found increased oxidative stress as compared to the controls. The GSH values in mdx muscles were decreased (mean±SEM; masseter 339.8±37.6 μg/g vs. 523.1±36.1 μg/g, temporal 304.1±49.6 μg/g vs.512.6±60.6 μg/g, tongue muscle 243.3±28. 8 μg/g vs. 474.9±40.1 μg/g; Fig. 1) as compared to normal mice. The GSH/GSSG ratio in mdx mice was consequently decreased. No significant differences in GSSG content and LPO levels were found between mdx and control mice.
The results imply that oxidative stress is present in all three studied mdx mouse masticatory muscles.
Experimental and toxicologic pathology: official journal of the Gesellschaft fur Toxikologische Pathologie 09/2011; 63(6):549-52. · 1.43 Impact Factor
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ABSTRACT: The present study aimed to examine the validity of the visual color assessment and an electronic tooth color measurement system by means of Shade Inspector™ in comparison with a gold standard. Additionally, reproducibility of electronic measurements was demonstrated by means of two reference systems.
Ceramic specimens of two thicknesses (h=1.6 mm, h=2.6 mm) were used. Three experienced dental technicians using the VITAPAN Classical(®) color scale carried out all visual tests. Validity of the visual assessment and the electronic measurements was confirmed separately for both thicknesses by means of lightness and hue of the VITAPAN Classical(®) color scale. Reproducibility of electronic measurements was confirmed by means of the VITAPAN Classical(®) and 3D-Master(®). The 3D-Master(®) data were calculated according to lightness, hue and chroma. Intraclass correlation coefficient (ICC) was used in assessing validity/reproducibility for lightness and chroma, Kappa statistics were used for hue. A level ≥0.75 was pre-established for ICC and ≥0.60 for the Kappa index. RESULTS OF VISUAL COLOR ASSESSMENT: Validity for lightness was good for both thicknesses; agreement rates for hue were inconsistent. ELECTRONIC MEASUREMENT: Validity for lightness was fair to good, hue values were below 0.60. Reproducibility of lightness was good to very good for both reference systems. Hue values (VITAPAN Classical(®)) for 1.6 mm test specimens were upside, for 2.6 mm below 0.60, Kappa values for 3D-Master(®) were ≥0.60 for all measurements, reproducibility of chroma was very good.
Validity was better for visual than for electronic color assessment. Reproducibility of the electronic device by means of the Shade Inspector™ was given for the VITAPAN Classical(®) and 3D-Master(®) systems.
Biomedizinische Technik/Biomedical Engineering 03/2011; 56(2):115-22. · 0.53 Impact Factor
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ABSTRACT: The activities of myogenic regulatory factors (MRF) and muscle growth factors increase in muscle that is undergoing regeneration, and may correspond to some specific changes. Little is known about the role of MRFs in masticatory muscles in mdx mice (the model of Duchenne muscular dystrophy) and particularly about their mRNA expression during the process of muscle regeneration. Using Taqman RT-PCR, we examined the mRNA expression of the MRFs myogenin and MyoD1 (myogenic differentiation 1), and of the muscle growth factors myostatin, IGF1 (insulin-like growth factor) and MGF (mechano-growth factor) in the masseter, temporal and tongue masticatory muscles of mdx mice (n = 6 to 10 per group). The myogenin mRNA expression in the mdx masseter and temporal muscle was found to have increased (P < 0.05), whereas the myostatin mRNA expressions in the mdx masseter (P < 0.005) and tongue (P < 0.05) were found to have diminished compared to those for the controls. The IGF and MGF mRNA amounts in the mdx mice remained unchanged. Inside the mdx animal group, gender-related differences in the mRNA expressions were also found. A higher mRNA expression of myogenin and MyoD1 in the mdx massterer and temporal muscles was found in females in comparison to males, and the level of myostatin was higher in the masseter and tongue muscle (P < 0.001 for all comparisons). Similar gender-related differences were also found within the control groups. This study reveals the intermuscular differences in the mRNA expression pattern of myogenin and myostatin in mdx mice. The existence of these differences implies that dystrophinopathy affects the skeletal muscles differentially. The finding of gender-related differences in the mRNA expression of the examined factors may indicate the importance of hormonal influences on muscle regeneration.
Cellular & Molecular Biology Letters 02/2011; 16(2):214-25. · 1.50 Impact Factor
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ABSTRACT: Duchenne muscular dystrophy (DMD) and murine X-linked muscular dystrophy (mdx), its murine model, are characterized by muscle damage and muscle weakness associated with inflammation and new vessel formation. Caveolins, dystrophin-associated proteins, are involved in the pathogenesis of DMD, because increased numbers of caveolae are found in DMD and mdx hindlimb muscles. Caveolae influence angiogenesis due to their content of vascular endothelial growth factor (VEGF) receptors. Orofacial muscles in mdx mice undergo muscle necrosis followed by muscle regeneration. To ascertain the role of caveolins and VEGF in the pathogenesis of dystrophic masticatory muscles, we examined the expression of caveolin-1 (cav-1), caveolin-3 (cav-3) and VEGF in control and mdx mice. In mdx masticatory muscles, no changes in transcript and protein levels of VEGF were found, whereas cav-1 and cav-3 expression was increased. Using immunohistochemistry, a strong sarcolemmal staining of caveolin-3 in regenerated muscle fibers was found. Furthermore, immunohistochemistry with the caveolin-1 antibody showed an increase in the amount of blood vessels in areas with regenerating muscle fibers. Dystrophic masticatory muscles showed changes comparable to those of hindlimb muscles in the expression of cav-1 and cav-3. The angiogenesis seems to be unaffected in the jaw muscles of mdx mice. We speculate that the increased caveolin expression could cause extensive and efficient muscle regeneration.
Folia Histochemica et Cytobiologica 01/2011; 49(2):291-8. · 0.81 Impact Factor
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Werner Götz,
Solvig Lenz,
Christoph Reichert,
Kai-Olaf Henkel,
Volker Bienengräber,
Laura Pernicka,
Karsten K H Gundlach,
Tomasz Gredes,
Thomas Gerber, Tomasz Gedrange,
Friedhelm Heinemann
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ABSTRACT: To test the probable osteoinductive properties of NanoBone, a new highly non-sintered porous nano-crystalline hydroxylapatite bone substitute embedded into a silica gel matrix, granules were implanted subcutaneously and intramuscularly into the back region of 18 mini pigs. After periods of 5 and 10 weeks as well as 4 and 8 months, implantation sites were investigated using histological and histomorphometric procedures. Signs of early osteogenesis could already be detected after 5 weeks. The later periods were characterized by increasing membranous osteogenesis in and around the granules leading to the formation of bone-like structures showing periosteal and tendon-like structures with bone marrow and focal chondrogenesis. Bone formation was better in the subcutaneous than in the intramuscular implantation sites. This ectopic osteogenesis is discussed with regard to the nanoporosity and microporosity of the material, physico-chemical interactions at its surface, the differentiation of osteoblasts, the role of angiogenesis and the probable involvement of growth factors. The results of this preliminary study indicate that this biomaterial has osteoinductive potential and induces the formation of bone structures, mainly in subcutaneous adipose tissue in the pig.
Folia Histochemica et Cytobiologica 12/2010; 48(4):589-96. · 0.81 Impact Factor
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ABSTRACT: Glycodelin (Gd), which is localized in cells of bronchial epithelium, type II pneumocytes and alveolar macrophages in rats and humans, plays an important role in the pulmonary immune response in asthmatic inflammation. In this study, sections of paraffin-embedded tumor adjacent lung tissue and sections of adenocarcinoma of the lung, squamous cell carcinoma of the lung and metastases of colonic adenocarcinoma were investigated for the distribution and expression of Gd using a polyclonal anti-Gd antibody. Glycodelin protein is located in the cytoplasm of bronchial epithelial cells, pneumocytes and alveolar macrophages. Furthermore, Gd is expressed in adenocarcinoma and squamous cell carcinoma of the lung as well as in lung metastases of colonic adenocarcinoma. Densitometric analyses showed a significantly increased expression of glycodelin protein in cancer tissue compared to tumor adjacent lung tissue. The Gd protein level was 1.7-2.6-fold increased in lung carcinoma compared to tumor adjacent lung tissue. The Gd protein level did not differ from each other between the investigated types of cancer tissue. Because these data validate the recent findings of Gd mRNA expression, it may be concluded that glycodelin plays an important role in the pathogenesis of lung cancer and lung metastases.
Acta histochemica 12/2010; 113(8):798-802. · 1.23 Impact Factor
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ABSTRACT: The dystrophin-deficient mouse (mdx) is a homologue animal model of Duchenne muscular dystrophy (DMD) and is characterized by slowly progressive muscle weakness accompanied by changes in myosin heavy chain (MyHC) composition. It is likely that the masticatory muscles undergo similar changes. The aim of this study was to examine the masticatory muscles (masseter, temporal, tongue, and soleus) of 100-day-old mdx and control mice (n = 8-10), and the fibre type distribution (by immunohistochemistry) as well as the expression of the corresponding MyHC messenger RNA (mRNA) (protein and mRNA expression, using Western blot or quantitative real-time polymerase chain reaction (RT-PCR)). Immunohistochemistry and western blot analysis revealed that the masticatory muscles in the control and mdx mice consisted mainly of type 2 fibres, whereas soleus muscle consisted of both type 1 and 2 fibres. In the masseter muscle, the mRNA in mdx mice was not different from that found in the controls. However, the mRNA content of the MyHC-2b isoform in mdx mice was lower in comparison with the controls in the temporal muscle [11.9 versus 36.9 per cent; P < 0.01; mean ± standard error of the mean (SEM), Student's unpaired t-test], as well as in the tongue muscle (65.7 versus 73.8 per cent; P < 0.05). Similarly, the content of MyHC-2x isoforms in mdx tongue muscle was lower than in the controls (25.9 versus 30.8 per cent; P < 0.05). The observed down-regulation of the MyHC-2x and MyHC-2b mRNA in the masticatory muscles of mdx mice may lead to changed fibre type composition. The different MyHC gene expression in mdx mice masticatory muscles may be seen as an adaptive mechanism to muscular dystrophy.
The European Journal of Orthodontics 12/2010; 33(6):613-9. · 0.89 Impact Factor
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ABSTRACT: In recent years, the use of immediately loaded implants became more acceptable as a standard protocol for completely edentulous lower jaw and/or partially edentulous upper jaw cases, predominantly in the anterior region, after it was one of the cornerstones of the early protocols to avoid any occlusal loading of the implants for at least 3 months. This technique could potentially provide immediate function and aesthetics to the patient. This review aims to present the clinical indications of the immediately loaded protocol according to the individual cases and the corresponding risk factors and contraindications. The clinical, biomechanical and biological requirements concerning bone quality, occlusal loading and implant primary stability are discussed. Primary stability in immediate loading is determined rather by surgical than biological parameters. Peri-implant osteogenesis leading to secondary stability depends on the same biological factors than in unloaded implant healing. However, specific mechanical effects on the biology of immediate loading osseointegration are yet to be investigated.
Biomedizinische Technik/Biomedical Engineering 10/2010; 55(6):311-5. · 0.53 Impact Factor
