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1.
J Microsc ; 294(2): 215-224, 2024 May.
Article in English | MEDLINE | ID: mdl-38556727

ABSTRACT

Global efforts to minimise carbon dioxide emissions are also leading to attempts to use calcined clays (CC) as a partial substitute for cement in concrete. While the hydration mechanism of such CC blended cements is now well understood, the range of effective admixtures like polycarboxylate ethers (PCE) is limited. There are PCE types that promise relatively high effectiveness, but the mechanisms of action are not yet sufficiently understood. For a detailed understanding of the adsorption of such PCEs, spatially resolved studies of the binder were performed using a combination of fluorescence and scanning electron microscopy. In a comparison of two superplasticisers, the investigations have shown different sites of preferred adsorption in a CC blended system and the results can be correlated with flow tests and setting behaviour. The investigations have shown that a certain PCE type has a higher adsorption on CC and other components of a blended system in comparison to other types.

2.
Int J Obes (Lond) ; 45(1): 45-55, 2021 01.
Article in English | MEDLINE | ID: mdl-32884101

ABSTRACT

BACKGROUND/OBJECTIVES: In Samoa, where 80% of the adult population is living with obesity, understanding the determinants of adiposity and growth during infancy may inform prevention efforts. We examined the association of a missense variant, rs373863828, in the CREBRF gene with body composition in Samoan infants. Adults with one or more copies of the rs373863828 minor allele (A) have higher odds of obesity, based on body-mass index (BMI), but paradoxically decreased odds of diabetes compared to those without the allele. Our study may offer novel insight into the natural history and pathogenesis of this unexpected relationship. SUBJECTS/METHODS: In a prospective study, we measured body composition in early infancy, and at 2- and 4-months of age using anthropometry and dual-energy x-ray absorptiometry (DXA). We genotyped subjects at the CREBRF rs373863828 locus and compared infants with (AA/AG) and without (GG) the variant. In longitudinal analyses, we calculated the absolute change in each outcome from the early infant to the 4-month assessment, adjusting for baseline and other covariates. RESULTS: In cross-sectional analyses, there was no significant difference in infant BMI or fat mass by genotype. After adjusting for covariates, infants with the variant had 4.0 ± 1.8 g more bone mass (p = 0.026) and 210.9 ± 79.6 g more lean mass (p = 0.009) at 4-months and accumulated 176.9 ± 73.0 g more lean mass between the early infant and 4-month assessment (p = 0.017). CONCLUSIONS: The CREBRF rs373863828 minor allele (A) was not associated with increased BMI or adiposity in Samoan infants, but instead with increased lean and bone mass. Our findings suggest that lean (i.e., muscle) and bone mass accretion should be explored as pathways to explain the "protective" effect of the CREBRF variant against diabetes.


Subject(s)
Body Composition/genetics , Mutation, Missense/genetics , Native Hawaiian or Other Pacific Islander , Tumor Suppressor Proteins/genetics , Adult , Cross-Sectional Studies , Female , Genotype , Humans , Infant , Infant, Newborn , Male , Native Hawaiian or Other Pacific Islander/genetics , Native Hawaiian or Other Pacific Islander/statistics & numerical data , Polymorphism, Single Nucleotide/genetics , Prospective Studies , Samoa/epidemiology , Young Adult
3.
Afr J Emerg Med ; 11(1): 175-181, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33194539

ABSTRACT

INTRODUCTION: Due to the COVID-19 crisis or any other mass casualty situation it might be necessary to give artificial ventilation to many affected patients. Contrarily, the worldwide availability of emergency ventilators is still a shortage, especially in developing countries. METHODS: Modes of artificial ventilation were compared and the most safe, easy to use, and lung protecting principle was optimized to fit all requirements of both emergency ventilation and cost-effective mass production. RESULTS: The presented research results describe a simplified device for a pressure-controlled ventilation which works without electricity according to a known principle. Just pressurized gas and a patient connection is required. The device enables the control of basic ventilator parameters such as peak inspiratory pressure, positive end-expiratory pressure and the ventilation frequency. Further, the device is semiadaptive to the patient's lung stiffness and automatically maintains minute volume through frequency adjustment. The machine can be manufactured by turning, milling and drilling and needs purchased components with costs less than 100 USD. A sterilization and thus a reuse is possible. DISCUSSION: The presented development does not describe a ready-to-purchase ventilator, it rather outlines a refined working principle for emergency ventilation and its easiest methods of production with a minimum of requirements. The presented research aims on providing an open-source guideline for production of an emergency ventilator using worldwide available methods and thus should inspire local researchers to do a reverse engineering and eventually to put it into operation following country-specific regulations. For long-term ventilation exceeding emergency purposes, a monitoring of alarms for disconnection and violation of desired ventilator parameters should be established. The ventilator is limited to a fixed ratio between PIP and PEEP. Moreover, the ventilation frequency depends on two parameters, which needs some training. Nevertheless, the ventilator provides basic features to enable an emergency ventilation with minimal prerequisites.

4.
J Mol Med (Berl) ; 97(3): 355-367, 2019 03.
Article in English | MEDLINE | ID: mdl-30617930

ABSTRACT

Fetal growth restriction (FGR) the leading cause of perinatal mortality and morbidity is highly related to abnormal placental development, and placentas from FGR pregnancies are often characterized by increased inflammation. However, the mechanisms of FGR-associated inflammation are far from being understood. NLRP7, a member of a family of receptors involved in the innate immune responses, has been shown to be associated with gestational trophoblastic diseases. Here, we characterized the expression and the functional role of NLRP7 in the placenta and investigated its involvement in the pathogenesis of FGR. We used primary trophoblasts and placental explants that were collected during early pregnancy, and established trophoblast-derived cell lines, human placental villi, and serum samples from early pregnancy (n = 38) and from FGR (n = 40) and age-matched controls (n = 32). Our results show that NLRP7 (i) is predominantly expressed in the trophoblasts during the hypoxic period of placental development and its expression is upregulated by hypoxia and (ii) increases trophoblast proliferation ([3H]-thymidine) and controls the precocious differentiation of trophoblasts towards syncytium (syncytin 1 and 2 and ß-hCG production and xCELLigence analysis) and towards invasive extravillous trophoblast (2D and 3D cultures). We have also demonstrated that NLRP7 inflammasome activation in trophoblast cells increases IL-1ß, but not IL-18 secretion. In relation to the FGR, we demonstrated that major components of NLRP7 inflammasome machinery are increased and that IL-1ß but not IL-18 circulating levels are increased in FGR. Altogether, our results identified NLRP7 as a critical placental factor and provided evidence for its deregulation in FGR. NLRP7 inflammasome is abundantly expressed by trophoblast cells. It is regulated by a key parameter of placental development, hypoxia. It controls trophoblast proliferation, migration, and invasion and exhibits anti-apoptotic role. NLRP7 machinery is deregulated in FGR pregnancies. KEY MESSAGES: NLRP7 inflammasome is abundantly expressed by trophoblast cells. It is regulated by a key parameter of placental development, hypoxia. It controls trophoblast proliferation, migration, and invasion and exhibits anti-apoptotic role. NLRP7 machinery is deregulated in FGR pregnancies.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Fetal Growth Retardation/metabolism , Placenta/metabolism , Trophoblasts/physiology , Adult , Cell Differentiation , Cell Line , Female , Humans , Hypoxia/metabolism , Interleukin-18/blood , Interleukin-1beta/blood , Pregnancy , Pregnancy Trimester, First/metabolism
5.
Mon Not R Astron Soc ; 478(1): 906-925, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30573924

ABSTRACT

We test if the cosmological zoom-in simulations of isolated galaxies from the FIRE project reproduce the properties of ultra diffuse galaxies (UDGs). We show that outflows that dynamically heat galactic stars, together with a passively aging stellar population after imposed quenching, naturally reproduce the observed population of red UDGs, without the need for high spin haloes, or dynamical influence from their host cluster. We reproduce the range of surface brightness, radius, and absolute magnitude of the observed red UDGs by quenching simulated galaxies at a range of different times. They represent a mostly uniform population of dark matter-dominated dwarf galaxies with M * ~ 108 M☉, low metallicity, and a broad range of ages; the more massive the UDGs, the older they are. The most massive red UDG in our sample(M * ~ 3 × 108 M☉) requires quenching at z ~ 3 when its halo reached M h ~ 1011M☉. Our simulated UDGs form with normal stellar-to-halo ratios and match the central enclosed masses and the velocity dispersions of the observed UDGs. Enclosed masses remain largely fixed across a broad range of quenching times because the central regions of their dark matter haloes complete their growth early. If our simulated dwarfs are not quenched, they evolve into bluer low surface brightness galaxies with M/L similar to observed field dwarfs. While our simulation sample covers a limited range of formation histories and halo masses, we predict that UDG is a common, and perhaps even dominant, galaxy type around M * ~ 108 M☉, both in the field and in clusters.

6.
Nat Chem ; 10(3): 355-362, 2018 03.
Article in English | MEDLINE | ID: mdl-29461525

ABSTRACT

The entatic state denotes a distorted coordination geometry of a complex from its typical arrangement that generates an improvement to its function. The entatic-state principle has been observed to apply to copper electron-transfer proteins and it results in a lowering of the reorganization energy of the electron-transfer process. It is thus crucial for a multitude of biochemical processes, but its importance to photoactive complexes is unexplored. Here we study a copper complex-with a specifically designed constraining ligand geometry-that exhibits metal-to-ligand charge-transfer state lifetimes that are very short. The guanidine-quinoline ligand used here acts on the bis(chelated) copper(I) centre, allowing only small structural changes after photoexcitation that result in very fast structural dynamics. The data were collected using a multimethod approach that featured time-resolved ultraviolet-visible, infrared and X-ray absorption and optical emission spectroscopy. Through supporting density functional calculations, we deliver a detailed picture of the structural dynamics in the picosecond-to-nanosecond time range.


Subject(s)
Coordination Complexes/chemistry , Copper/chemistry , Photochemical Processes , Density Functional Theory , Electron Transport , Molecular Structure
7.
J Gynecol Obstet Biol Reprod (Paris) ; 45(8): 841-848, 2016 Oct.
Article in French | MEDLINE | ID: mdl-27593614

ABSTRACT

OBJECTIVES: To characterize the indications of primary cesarean sections and discuss the various possibilities to reduce them. MATERIALS AND METHODS: Retrospective study, carried out over a period of 1 year in a university hospital having a level 3 perinatal activity, including the 499 primary cesarean sections of 2013. Two groups were defined by parity: nulliparous patients (group 1) and multiparous patients who had never previously been delivered by cesarean section (group 2). We have assessed the indication of every primary cesarean section and health status of newborns in each group. RESULTS: Groups 1 and 2 respectively included 369 and 130 patients. The cesarean section rate in 2013 was 24.7% with a primary cesarean section rate of 17%. Seventy-four percent of the primary caesarean deliveries were performed on nulliparous women and 26% on multiparous (P<0.001). Sixty-three percent of the primary caesarean deliveries were performed on nulliparous women with a singleton fetus in cephalic presentation. The most common indications for primary cesarean delivery were non-reassuring fetal heart rate tracing (47.1%), failure to progress (24.8%) for which nulliparous women were more involved (29% vs. 13%, P<0.001) and fetal malpresentation (9.6%). CONCLUSION: Further analysis of fetal heart rate during labor, a larger use of second line means to evaluate the fetal status during labor, using 6cm as the cut off for active labor, and encouraging vaginal operative delivery constitute the best way to decrease the primary cesarean section rate.


Subject(s)
Cesarean Section/statistics & numerical data , Heart Rate, Fetal , Hospitals, University/statistics & numerical data , Obstetric Labor Complications/epidemiology , Parity , Adult , Female , France , Humans , Obstetric Labor Complications/surgery , Pregnancy , Retrospective Studies , Young Adult
9.
Growth Horm IGF Res ; 20(5): 345-55, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20655258

ABSTRACT

OBJECTIVE: Bovine growth hormone (bGH) transgenic mice develop severe kidney damage. This damage may be due, at least in part, to changes in gene expression. Identification of genes with altered expression in the bGH kidney may identify mechanisms leading to damage in this system that may also be relevant to other models of kidney damage. DESIGN: cDNA subtraction libraries, northern blot analyses, microarray analyses and real-time reverse transcription polymerase chain reaction (RT/PCR) assays were used to identify and verify specific genes exhibiting differential RNA expression between kidneys of bGH mice and their non-transgenic (NT) littermates. RESULTS: Immunoglobulins were the vast majority of genes identified by the cDNA subtractions and the microarray analyses as being up-regulated in bGH. Several glycoprotein genes and inflammation-related genes also showed increased RNA expression in the bGH kidney. In contrast, only a few genes were identified as being significantly down-regulated in the bGH kidney. The most notable decrease in RNA expression was for the gene encoding kidney androgen-regulated protein. CONCLUSIONS: A number of genes were identified as being differentially expressed in the bGH kidney. Inclusion of two groups, immunoglobulins and inflammation-related genes, suggests a role of the immune system in bGH kidney damage.


Subject(s)
Gene Expression , Growth Hormone/genetics , Immunity/genetics , Kidney Diseases/genetics , Kidney/metabolism , Animals , Cattle , Down-Regulation , Female , Gene Expression Profiling , Glycoproteins/metabolism , Immunoglobulins/genetics , Kidney/immunology , Kidney/pathology , Kidney Diseases/pathology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Up-Regulation
10.
Lett Appl Microbiol ; 45(5): 504-7, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17908226

ABSTRACT

AIMS: To determine the potential for naturally occurring Shiga toxin-negative Escherichia coli O157 to acquire stx(2) genes. METHODS AND RESULTS: Multiple E. coli O157:H7 isolates positive for eae and ehxA, but not for stx genes, were isolated from cattle, water trough sediment, animal bedding and wild bird sources on several Ohio dairy farms. These isolates were experimentally lysogenized by stx(2)-converting bacteriophage. CONCLUSIONS: Shiga toxin-negative strains of E. coli O157 are present in multiple animal and environmental sources. SIGNIFICANCE AND IMPACT OF THE STUDY: Shiga toxin-negative strains of E. coli O157 present in the food production environment are able to acquire the stx genes, demonstrating their potential to emerge as new Shiga toxin-producing E. coli strains.


Subject(s)
Birds/microbiology , Cattle/microbiology , DNA, Bacterial/analysis , Escherichia coli O157/isolation & purification , Shiga Toxin/genetics , Animals , Environmental Microbiology , Escherichia coli O157/genetics , Food Microbiology , Polymerase Chain Reaction , Shiga Toxin/biosynthesis
11.
J Anim Sci ; 85(13 Suppl): E73-80, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17145967

ABSTRACT

Bovine manure is an important source of Escherichia coli O157 contamination of the environment and foods; therefore, effective interventions targeted at reducing the prevalence and magnitude of fecal E. coli O157 excretion by live cattle (preharvest) are desirable. Preharvest intervention methods can be grouped into 3 categories: 1) exposure reduction strategies, 2) exclusion strategies, and 3) direct antipathogen strategies. Exposure reduction involves environmental management targeted at reducing bovine exposure to E. coli O157 through biosecurity and environmental niche management such as feed and drinking water hygiene, reduced exposure to insects or wildlife, and improved cleanliness of the bedding or pen floor. In the category of exclusion, we group vaccination and dietary modifications such as selection of specific feed components; feeding of prebiotics, probiotics, or both; and supplementation with competitive exclusion cultures to limit proliferation of E. coli O157 in or on exposed animals. Direct antipathogen strategies include treatment with sodium chlorate, antibiotics, bacteriophages, in addition to washing of animals before slaughter. Presently, only 1 preharvest control for E. coli O157 in cattle has been effective and has gained widespread adoption-the feeding probiotic Lactobacillus acidophilus. More research into the effectiveness of parallel and simultaneous application of 1 or more preharvest control strategies, as well as the identification of new pre-harvest control methods, may provide practical means to substantially reduce the incidence of human E. coli O157-related illness by intervening at the farm level.


Subject(s)
Cattle Diseases/prevention & control , Escherichia coli Infections/veterinary , Escherichia coli O157 , Food Contamination/prevention & control , Animal Feed , Animals , Cattle , Escherichia coli Infections/prevention & control , Feces/microbiology , Food Microbiology , Humans , Lactobacillus acidophilus/metabolism , Probiotics/pharmacology
12.
Z Gerontol Geriatr ; 39(5): 365-70, 2006 Oct.
Article in German | MEDLINE | ID: mdl-17039292

ABSTRACT

A rehabilitation care management oriented towards the severity of the disease, the individual competence and the patient's needs essentially improves the effectivity and the sustainability of inpatient rehabilitation. The Institute of Gerontology of the University of Heidelberg is developing an assessment for elderly stroke patients to optimize placement decision by an early rehabilitation prognosis. Data concerning functional, cognitive and psychological status were collected in 267 patients participating in a postacute rehabilitation program on admission, after two weeks and on discharge and six weeks later. In this article are presented the study design and patients' characteristics during the rehabilitation process. The first assessment at admission gives important information about the sustainability of the ADL-competence after discharge. Severe stroke, premorbid ADL-competence, cognitive impairment, communication problems, depression and higher age were found to be predictors for the outcome of the rehabilitation process.


Subject(s)
Geriatric Assessment/methods , Geriatric Assessment/statistics & numerical data , Health Services for the Aged/statistics & numerical data , Program Evaluation , Stroke Rehabilitation , Stroke/diagnosis , Aged , Aged, 80 and over , Female , Germany/epidemiology , Humans , Male , Outcome Assessment, Health Care , Pilot Projects , Prognosis , Reproducibility of Results , Sensitivity and Specificity , Stroke/epidemiology , Treatment Outcome
14.
Clin Oral Implants Res ; 10(2): 111-9, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10219130

ABSTRACT

The purpose of this study was to examine the healing potential and re-osseointegration in peri-implant infection defects adjacent to various implant surfaces. In 7 female Beagle dogs, a total of 41 titanium oral implants (ITI, Straumann, Waldenburg; Switzerland) with a sink depth of 6 mm (diameter 2.8 mm) were placed transmucosally. Four different surface configurations (TPS: titanium plasma sprayed (10); SLA: sand blasted and acid-etched (13); M: machined and smooth (11); TPS furc.: titanium plasma sprayed with coronally placed perforation to mimic a furcation (7) were distributed among the animals and locations. Following a healing period of 3 months, silk ligatures were placed and oral cleaning procedures abolished for 4 months to induce a vertical bone loss of about 40%. Following mechanical and chemical cleansing (chlorhexidine and metronidazole) and disinfection, the lesions were either sham operated (11) or subjected to a GTR procedure using ePTFE (30). After 6 months of healing the animals were killed and the jaws histologically evaluated. Six membranes were lost TPS: (1); SLA: (2); M: (2); TPS furc: (1) and 3 membranes exposed TPS: (1); M: (2) and excluded from further evaluation. Owing to the loss of 1 implant and infection of the membranes in the TPS furc group, this implant configuration was discarded from further analysis. For TPS surfaces, bone fill was 2.6 mm (73% of the distance from the bottom of the defect to the shoulder of the implant) sites with (4 GTR) and 0.33 mm (14%) for sites without membrane (2 controls). Re-osseointegration was 0.5 mm (14%) in the test group and 0.3 mm (14%) in the control. For SLA surfaces bone fill was 2.3 mm (83%) for sites with (7 GTR) and 0.41 mm (15%) for sites without membranes (4 controls). Re-osseointegration was 0.6 mm (20%) and 0.3 mm (11%) respectively. Corresponding values for M surfaces were 2.2 mm (62%) with 4 GTR) and 0.82 mm (31%) without membranes. Re-osseointegration was 0.07 mm (2%) and 0.19 mm (7%) respectively. This study has documented that peri-implant infections defects may heal with bone fill provided that the infection is controlled through effective antibacterial therapy. However, true reosseointegration appears to be difficult to achieve.


Subject(s)
Dental Implants/adverse effects , Guided Tissue Regeneration, Periodontal , Osseointegration , Periodontitis/etiology , Prosthesis-Related Infections/drug therapy , Alveolar Process/physiology , Animals , Anti-Infective Agents/therapeutic use , Bone Regeneration , Chlorhexidine/therapeutic use , Dental Plaque/complications , Dental Prosthesis Design , Dogs , Female , Membranes, Artificial , Metronidazole/therapeutic use , Periodontitis/therapy , Polytetrafluoroethylene , Prosthesis-Related Infections/etiology , Retreatment , Statistics, Nonparametric , Wound Healing
15.
Int J Periodontics Restorative Dent ; 19(3): 289-97, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10635175

ABSTRACT

The success of endosseous dental implants is enhanced when sufficient bone is present to stabilize the implant. If adequate bone for full coverage of the implant is not possible, then the use of guided bone regeneration to regenerate the missing bone has been shown to be a predictable solution. Defect size can often limit the amount of soft tissue available for coverage of the membrane, which is essential in obtaining an optimal result when using regenerative and osseointegrative principles. The treatment philosophy demonstrated in this case report uses controlled subperiosteal tissue expansion to facilitate the incorporation of guided bone regeneration with the subsequent placement of endosseous dental implants. This treatment modality provided a successful treatment for an otherwise compromised case.


Subject(s)
Maxilla/surgery , Maxillofacial Injuries/surgery , Periosteum , Tissue Expansion/methods , Adult , Bone Regeneration , Dental Implantation, Endosseous , Guided Tissue Regeneration, Periodontal , Humans , Male , Patient Care Planning , Periosteum/surgery
16.
Environ Sci Pollut Res Int ; 5(1): 28-36, 1998.
Article in English | MEDLINE | ID: mdl-19002625

ABSTRACT

Legume root nodules are the site of biological nitrogen fixation in the Rhizobium-legume symbiosis. Nodules are structures unique to this symbiosis and they are morphologically as well as physiologically distinct from other plant organs. Organic substances affecting the macro- or microsymbionts vitality, such as PAHs (WETZEL: et al., 1991), reduce nodulation even before visible damage to the plant can be detected. We present data that the formation of nodules (nodulation) may also serve for ecotoxicological evaluation of heavy metals in different binding states. Tests were performed in petri dishes with alfalfa (lucerne) seedlings inoculated with Rhizobium meliloti. Cultivation took place in growth cabinets with carefully standardized and documented growth conditions. Data from stressed plants was recorded after 14 days of cultivation on contaminated substrate. A dose responsive decrease in nodulation was found after application of cadmium acetate, cadmium iodide, cadmium chloride, sodium salts of arsenate and arsenite, arsenic pentoxide, and lead nitrate, whereas lead acetate showed no effect up to a concentration of 3 microM. The dose response curves were used to calculate EC10, EC50 and EC90 values. EC50 values for cadmium compounds range from 1.5 to 9.5 pM. Testing different arsenic compounds results in EC50 from 2.6 to 20.1 microM. EC50 of lead nitrate is 2.2 microM. The sensitivity, reproducibility and reliability of this test system is discussed compared to established biotests.

17.
Clin Oral Implants Res ; 6(3): 155-63, 1995 Sep.
Article in English | MEDLINE | ID: mdl-7578791

ABSTRACT

The placement of oral implants into jaw bone has a high predictability provided an adequate bone volume surrounding the implant is present to ensure primary stability and resistance to functional loading forces after completion of osseointegration. In the distal area of the maxilla, an adequate bone volume is often lacking because of the proximity of the sinus cavities. The aim of this study was to evaluate histologically the simultaneous placement of endosseous implants into the sinus cavity and the surgical elevation of the sinus floor including filling the cavity with different grafting materials. In 9 sinus areas of 5 beagle dogs, 9 titanium implants (ITI Dental Implant System) were placed, and the void space of the sinus cavity was filled simultaneously with either demineralized freeze-dried human cortical bone (Musculoskeletal Transplant Foundation), resorbable hydroxyapatite (Osteogen) or natural cancelleous bovine bone mineral (Bio-Oss). To study bone formation, fluorochrome markers (tetracycline HCl and calcein green) were used at 2 and 8 weeks. Clinically, all implants healed uneventfully, and 5 months after implant placement the dogs were killed for histologic evaluation. All implants exhibited osseointegration within the pre-existing cortical bone of the sinus floor. The implants surrounded by freeze-dried bone xenografts yielded no formation of new bone, whereas the sites with hydroxyapatite or natural bovine bone mineral demonstrated newly formed bone with direct contact at the implant surface. The average extent of bone to implant contact was 25% (SD = 10.6%) and 27% (SD = 8.8%), respectively in relation to the length of the originally denuded implant surface.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Bone Substitutes , Bone Transplantation/methods , Dental Implantation, Endosseous/methods , Dental Implants , Maxillary Sinus/surgery , Oral Surgical Procedures, Preprosthetic/methods , Osseointegration , Animals , Bone Regeneration , Cattle , Dogs , Durapatite , Female , Humans , Membranes, Artificial , Minerals , Polytetrafluoroethylene
19.
Clin Oral Implants Res ; 5(4): 191-201, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7640332

ABSTRACT

Periodontal probing is commonly used for assessing both the status of gingival health and the connective tissue attachment level around teeth. The role of probing around endosseous implants still remains unclear. The purpose of this study was to determine the histological level of probe penetration in healthy and inflamed mucosal tissues around implants. Five beagle dogs were used and a total of 30 one-stage, Titanium Plasma Spary (TPS)-coated implants of the ITI type were placed in the mandibles. After the healing period with meticulous oral hygiene, the dogs were divided into 3 groups: 1) clinical healthy mucosal tissues; 2) experimental mucositis (3 dogs); and 3) experimental ligature-induced peri-implantitis (2 dogs). Four months after implant placement, respectively 6 months in the third group, 60 probes were placed with a standardized force of 0.2 N and fixed at the mesial and distal aspects of the implants. Probing depth, clinical attachment level (CAL), Plaque Index (PlI) and Gingival Index (GI) were assessed throughout the study. Tissue sections were obtained for histometrical analysis. In the healthy group, the mean PII was 0.47, the GI 0.06 and the clinical probing depth (CPD) 2.12 mm. In the mucositis group the PlI was 1.61, the GI 1.61 and the CPD 1.87 mm. In the peri-implantitis group the PlI was 1.96, the GI 2.05 and the CPD 3.73 mm. The histologic results show that the probes were able to identify the connective tissue adhesion level in the healthy group with a mean error of -0.05 mm (mean histologic probing depth (HPD): 1.75 mm) and, in the mucositis group, with -0.02 mm (mean HPD: 1.62 mm). Probe penetration increased with the degree of inflammation and in the peri-implantitis group the probe exceeded the connective tissue level by a mean 0.52 mm (mean HPD: 3.8 mm). Therefore, probing around implants represents a good technique for assessing the status of peri-implant mucosal health or disease.


Subject(s)
Dental Implants , Periodontics/instrumentation , Periodontitis/diagnosis , Animals , Dental Implantation, Endosseous/instrumentation , Dental Implants/adverse effects , Dental Plaque Index , Dogs , Female , Gingivitis/diagnosis , Gingivitis/etiology , Linear Models , Mouth Mucosa/pathology , Osseointegration , Periodontal Index , Periodontitis/etiology , Stomatitis/diagnosis , Stomatitis/etiology
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