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1.
Viruses ; 13(4)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33918079

RESUMO

Vascular changes represent a characteristic feature of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection leading to a breakdown of the vascular barrier and subsequent edema formation. The aim of this study was to provide a detailed characterization of the vascular alterations during SARS-CoV-2 infection and to evaluate the impaired vascular integrity. Groups of ten golden Syrian hamsters were infected intranasally with SARS-CoV-2 or phosphate-buffered saline (mock infection). Necropsies were performed at 1, 3, 6, and 14 days post-infection (dpi). Lung samples were investigated using hematoxylin and eosin, alcian blue, immunohistochemistry targeting aquaporin 1, CD3, CD204, CD31, laminin, myeloperoxidase, SARS-CoV-2 nucleoprotein, and transmission electron microscopy. SARS-CoV-2 infected animals showed endothelial hypertrophy, endothelialitis, and vasculitis. Inflammation mainly consisted of macrophages and lower numbers of T-lymphocytes and neutrophils/heterophils infiltrating the vascular walls as well as the perivascular region at 3 and 6 dpi. Affected vessels showed edema formation in association with loss of aquaporin 1 on endothelial cells. In addition, an ultrastructural investigation revealed disruption of the endothelium. Summarized, the presented findings indicate that loss of aquaporin 1 entails the loss of intercellular junctions resulting in paracellular leakage of edema as a key pathogenic mechanism in SARS-CoV-2 triggered pulmonary lesions.

2.
Front Immunol ; 12: 640842, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912167

RESUMO

Neutrophil extracellular traps (NETs) have been identified as one pathogenetic trigger in severe COVID-19 cases and therefore well-described animal models to understand the influence of NETs in COVID-19 pathogenesis are needed. SARS-CoV-2 infection causes infection and interstitial pneumonia of varying severity in humans and COVID-19 models. Pulmonary as well as peripheral vascular lesions represent a severe, sometimes fatal, disease complication of unknown pathogenesis in COVID-19 patients. Furthermore, neutrophil extracellular traps (NETs), which are known to contribute to vessel inflammation or endothelial damage, have also been shown as potential driver of COVID-19 in humans. Though most studies in animal models describe the pulmonary lesions characterized by interstitial inflammation, type II pneumocyte hyperplasia, edema, fibrin formation and infiltration of macrophages and neutrophils, detailed pathological description of vascular lesions or NETs in COVID-19 animal models are lacking so far. Here we report different types of pulmonary vascular lesions in the golden Syrian hamster model of COVID-19. Vascular lesions included endothelialitis and vasculitis at 3 and 6 days post infection (dpi), and were almost nearly resolved at 14 dpi. Importantly, virus antigen was present in pulmonary lesions, but lacking in vascular alterations. In good correlation to these data, NETs were detected in the lungs of infected animals at 3 and 6 dpi. Hence, the Syrian hamster seems to represent a useful model to further investigate the role of vascular lesions and NETs in COVID-19 pathogenesis.

3.
Head Face Med ; 17(1): 3, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33531044

RESUMO

BACKGROUND: Orthodontic root resorptions are frequently investigated in small animals, and micro-computed tomography (µCT) enables volumetric comparison. Despite, due to overlapping histograms from dentine and bone, accurate quantification of root resorption is challenging. The present study aims at (i) validating a novel automated approach for tooth segmentation (ATS), (ii) to indicate that matching of contralateral teeth is eligible to assess orthodontic tooth movement (OTM) and root resorption (RR), (iii) and to apply the novel approach in an animal trial performing orthodontic tooth movement. METHODS: The oral apparatus of three female mice were scanned with a µCT. The first molars of each jaw and animal were segmented using ATS (test) and manually (control), and contralateral volumes were compared. Agreement in root volumes and time efficiency were assessed for method validation. In another n = 14 animals, the left first upper molar was protracted for 11 days at 0.5 N, whereas the contralateral molar served as control. Following ATS, OTM and RR were estimated. RESULTS: ATS was significantly more time efficient compared to the manual approach (81% faster, P < 0.01), accurate (volume differences: - 0.01 ± 0.04 mm3), and contralateral roots had comparable volumes. Protracted molars had significantly lower root volumes (P = 0.03), whereas the amount of OTM failed to reveal linear association with RR (P > 0.05). CONCLUSIONS: Within the limits of the study, it was demonstrated that the combination of ATS and registration of contralateral jaws enables measurements of OTS and associated RR in µCT scans.


Assuntos
Reabsorção da Raiz , Animais , Feminino , Camundongos , Dente Molar/diagnóstico por imagem , Roedores , Reabsorção da Raiz/diagnóstico por imagem , Técnicas de Movimentação Dentária , Raiz Dentária , Microtomografia por Raio-X
4.
Int J Implant Dent ; 6(1): 63, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33073302

RESUMO

BACKGROUND: To evaluate the prevalence of peri-implant disease after immediate implant placement and loading. MATERIAL AND METHODS: This cross-sectional analysis included a total of 47 patients with 64 implants exhibiting a mean loading time of 2 to 10 years (4.23 ± 1.7 years). The surgical and prosthetic procedures were standardized in all patients. Peri-implant health and disease was assessed based on the established case definitions. RESULTS: The prevalence of peri-implant health, peri-implant mucositis, and peri-implantitis amounted to 38.3%, 57.5%, and 4.2% of the patients, respectively. Mucosal recession of 1 mm was present at 4 (6%) implants. No suppuration, pain, or implant failures were reported. Ordinal logistic regression revealed that reduced keratinized mucosa height was significantly associated with the diagnosis of peri-implant mucositis and peri-implantitis (OR = 0.514, P = 0.0125). CONCLUSION: Immediate implant placement and loading was associated with high success rates at 2 to 10 years.

6.
Clin Oral Implants Res ; 31(12): 1253-1260, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33047356

RESUMO

OBJECTIVES: The current COVID-19 outbreak in conjunction with the need to provide safe dental treatments and the limited knowledge on the efficacy of protective measures has posed dentists into a challenging situation. Therefore, the present article aimed at collecting experiences and recommendations of frontline clinical experts on critical aspects of dental treatment provision during pandemic. MATERIAL & METHODS: From a total of 32 European countries, one leading academic expert in Oral and Maxillofacial Surgery or Oral Surgery per country was asked to participate in an anonymous online 10-item survey on COVID-19 covering the topics of safety of dental settings, personal protective equipment (PPE), and patient-related measures to reduce transmission risk. Data collection took place from April 12th to May 22nd, 2020. RESULTS: A total of 27 experts from different European countries completed the survey. The transmission risk of SARS-CoV-2 in dental settings for aerosol-generating procedures was considered high by all experts except two. For aerosol-free and aerosol-generating procedures, more than 80% of the experts recommended face protection and caps for every single treatment. For aerosol-generating procedures, additional measures (FFP2/FFP3 masks and gowns) were suggested by the vast majority of the experts. To reduce transmission risk, all experts recommended limiting aerosol-generating procedures and reducing the number of patients in waiting areas as well as hand hygiene for the patients. CONCLUSION: The limitation of aerosol-generating procedures along with the usage of adequate personal protection equipment was considered to be crucial to protect dental healthcare providers and patients, thus reducing the transmission risk of COVID-19.

7.
Clin Implant Dent Relat Res ; 22(5): 647-653, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32876385

RESUMO

BACKGROUND: To volumetrically assess the bone microstructure following vertical alveolar ridge augmentation using differently conditioned autogenous tooth roots (TR) and second-stage implant placement. MATERIALS AND METHODS: The upper premolars were bilaterally extracted in n = 4 beagle dogs and randomly assigned to either autoclavation (TR-A) or no additional treatment (TR-C). Subsequently, TR were used as block grafts for vertical alveolar ridge augmentation in both lower quadrants. At 12 weeks, titanium implants were inserted and left to heal 3 weeks. Microcomputed tomography was used to quantify bone volume per tissue volume (BV/TV), trabecular thickness (Tb.Th), and trabecular spacing (Tb.Sp) at vestibular (v) and oral (o) aspects along the implant and in the augmented upper half of the implant, respectively. RESULTS: Median BV/TV [TR-C: 51.33% (v) and 70.42% (o) vs TR-A: 44.05% (v) and 64.46% (o)], Tb.th [TR-C: 0.22 mm (v) and 0.27 mm (o) vs TR-A: 0.23 mm (v) and 0.29 mm (o)] and Tb.Sp [TR-C: 0.26 mm (v) and 0.13 mm (o) vs TR-A: 0.29 µm (v) and 0.15 mm (o)] values were comparable in both groups. CONCLUSION: Both TR-C and TR-A grafts were associated with a comparable bone microstructure within the grafted area.

8.
Bone ; 141: 115569, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32745691

RESUMO

Treatment of atrophic non-unions, especially in long bones is a challenging problem in orthopedic surgery due to the high revision and failure rate after surgical intervention. Subsequently, there is a certain need for a supportive treatment option besides surgical treatment. In our previous study we gained first insights into the dynamic processes of atrophic non-union formation and observed a prolonged inflammatory reaction with upregulated TNF-α levels and bone resorption. In this study we aimed to improve bone regeneration of atrophic non-unions via TNF-α modulation in a previously established murine femoral segmental defect model. Animals that developed atrophic non-unions of the femur after 5 and 10 weeks were treated systemically for 10 and 5 weeks with Etanercept, a soluble TNF-α antibody. µCT scans and histology revealed bony bridging of the fracture gap in the treatment group, while bone formation in control animals without treatment was not evident. Moreover, osteoclasts were markedly decreased via modulation of the RANKL/OPG axis due to Etanercept treatment. Additionally, immunomodulatory effects via Etanercept could be observed as further inflammatory agents, such as TGF-ß, IL6, MMP9 and 13 were decreased in both treatment groups. This study is the first showing beneficial effects of Etanercept treatment on bone regeneration of atrophic non-union formation. Moreover, the results of this study provide a new and promising therapeutic option which might reduce the failure rate of revision surgeries of atrophic non-unions.

9.
J Cell Mol Med ; 24(16): 9332-9348, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32627957

RESUMO

Sarcomas especially of histiocytic origin often possess a poor prognosis and response to conventional therapies. Interestingly, tumours undergoing mesenchymal to epithelial transition (MET) are often associated with a favourable clinical outcome. This process is characterized by an increased expression of epithelial markers leading to a decreased invasion and metastatic rate. Based on the failure of conventional therapies, viral oncolysis might represent a promising alternative with canine distemper virus (CDV) as a possible candidate. This study hypothesizes that a CDV infection of canine histiocytic sarcoma cells (DH82 cells) triggers the MET process leading to a decreased cellular motility. Immunofluorescence and immunoblotting were used to investigate the expression of epithelial and mesenchymal markers followed by scratch assay and an invasion assay as functional confirmation. Furthermore, microarray data were analysed for genes associated with the MET process, invasion and angiogenesis. CDV-infected cells exhibited an increased expression of epithelial markers such as E-cadherin and cytokeratin 8 compared to controls, indicating a MET process. This was accompanied by a reduced cell motility and invasiveness. Summarized, these results suggest that CDV infection of DH82 cells triggers the MET process by an increased expression of epithelial markers resulting in a decreased cell motility in vitro.

10.
Clin Oral Implants Res ; 31(9): 881-888, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32645746

RESUMO

OBJECTIVES: To assess the short-term clinical outcomes of lateral augmentation of deficient extraction sockets and two-stage implant placement using autogenous tooth roots (TR). MATERIAL AND METHODS: A total of n = 13 patients (13 implants) were available for the analysis. At the time of tooth extraction, each subject had received lateral augmentation using the respective non-retainable but non-infected tooth root where the thickness of the buccal bone was <0.5 mm or where a buccal dehiscence-type defect was present. Titanium implants were placed after a submerged healing period of 6 months and loaded after 20 ± 2 weeks (V8). Clinical parameters (e.g., bleeding on probing-BOP, probing pocket depth-PD, mucosal recession-MR, clinical attachment level-CAL) were recorded at V8 and after 26 ± 4 weeks (V9) of implant loading. RESULTS: At V9, all patients investigated revealed non-significant changes in mean BOP (-19.23 ± 35.32%), PD (0.24 ± 0.49 mm), MR (0.0 ± 0.0 mm) and CAL (0.24 ± 0.49 mm) values, respectively. There was no significant correlation between the initial gain in ridge width and changes in BOP and PD values. CONCLUSIONS: The surgical procedure was associated with stable peri-implant tissues on the short-term.

11.
J Clin Med ; 9(6)2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32545477

RESUMO

Dental clinics were suspected to be a hotspot for nosocomial transmission of coronavirus disease 19 (COVID-19), yet there has been no clear recommendation about emergency dental care and appropriate personal protective equipment during pandemics. In this paper, we aim to summarize recommendations for (i) patient risk assessment, (ii) patient triage, and (iii) measures to prevent infection of health professionals and nosocomial transmission in dental clinics. The available evidence was collected by performing searches on PubMed, Embase, and Cochrane databases. We reviewed papers on COVID-19, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), influenza, and related respiratory viral diseases. Legal and ethical frameworks, as well as international (e.g., World Health Organization (WHO)) and national (e.g., public health institutes, dental associations) guidelines were screened to summarize recommendations related to dental emergency care. To assess the patient risk, a questionnaire was developed to classify patients at unknown, high, and very high risk. Patient triage recommendations were summarized in a flow chart that graded the emergency level of treatments (i.e., urgent, as soon as possible, and postpone). Measures to prevent disease transmission based on current evidence were grouped for dental health professionals, dental clinics, and patients. The present recommendations may support health professionals implement preventative measures during the pandemic.

12.
J Mol Med (Berl) ; 98(6): 897-906, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32424558

RESUMO

Impaired bone homeostasis caused by osteomyelitis provokes serious variations in the bone remodeling process, thereby involving multiple inflammatory cytokines to activate bone healing. We have previously established a mouse model for post-traumatic osteomyelitis and studied bone regeneration after sufficient debridement. Moreover, we could further characterize the postinfectious inflammatory state of bony defects after debridement with elevated osteoclasts and decreased bone formation despite the absence of bacteria. In this study, we investigated the positive effects of Wnt-pathway modulation on bone regeneration in our previous established mouse model. This was achieved by local application of Wnt3a, a recombinant activator of the canonical Wnt-pathway. Application of Wnt3a could enhance new bone formation, which was verified by histological and µ-CT analysis. Moreover, histology and western blots revealed enhanced osteoblastogenesis and downregulated osteoclasts in a RANKL-dependent manner. Further analysis of Wnt-pathway showed downregulation after bone infections were reconstituted by application of Wnt3a. Interestingly, Wnt-inhibitory proteins Dickkopf 1 (DKK1), sclerostin, and secreted frizzled protein 1 (sFRP1) were upregulated simultaneously to Wnt-pathway activation, indicating a negative feedback for active form of Beta-catenin. In this study, we could demonstrate enhanced bone formation in defects caused by post-traumatic osteomyelitis after Wnt3a application. KEY MESSAGES: Osteomyelitis decreases bone regeneration Wnt3a restores bone healing after infection Canonical Wnt-pathway activation with negative feedback.

14.
Prog Orthod ; 21(1): 5, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32064547

RESUMO

BACKGROUND: In dental implantology, the development of stability over time is a well-investigated topic. In case of orthodontic mini-implants, quantitative data for long-term stability is not available yet. This study aims to clinically investigate the long-term stability of mini-implants inserted in the midsagittal suture of the anterior palate. Moreover, the influence of the length of implants was elucidated. The stability of 2 × 9 and 2 × 11 mm mini-implants after orthodontic treatment (9 mm, 2.84 years ± 1.25 years; 11 mm, 3.17 years ± 0.96 years) was assessed by resonance frequency analysis (RFA). The obtained long-term pieces of data were compared with each other (9 mm vs 11 mm), as well as with the data from the matched early stability groups, to assess the initial and early secondary stability after the insertion from previous clinical trials. RESULTS: For both lengths, the long-term stability (2 × 9 mm, 25.12 ± 7.11, n = 21; 2 × 11 mm, 24.39 ± 5.82, n = 18) was significantly lower than primary stability (2 × 9 mm, 36.14 ± 6.08, n = 19; 2 × 11 mm, 33.35 ± 3.53, n = 20). The differences within the groups disappeared over the initial healing period: after 4 weeks for the 2 × 9 mm implants and after 2 weeks for the 2 × 11 mm implants. Also, the 2 × 9 mm and 2 × 11 mm implants showed comparable long-term stability values. CONCLUSION: The stability of midpalatal mini-implants does not change in the long term after the initial healing period. Moreover, 2 × 9 mm mini-implants seem to be appropriate for orthodontic anchorage, as the stability of 2 × 11 mm implants is not higher. Therefore, owing to lower invasiveness, 2 × 9 mm implants should be preferred.


Assuntos
Implantes Dentários , Procedimentos de Ancoragem Ortodôntica , Palato , Análise de Frequência de Ressonância , Cicatrização
15.
Am J Orthod Dentofacial Orthop ; 156(3): 345-354, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31474264

RESUMO

INTRODUCTION: Orthodontic mini-implants are frequently used to provide additional anchorage for orthodontic appliances. The anterior palate is frequently used owing to sufficient bone quality and low risk of iatrogenic trauma to adjacent anatomical structures. Even though the success rates in this site are high, failure of an implant will result in anchorage loss. Therefore, implants should be placed in areas with sufficient bone quality. The aim of the present study was to identify an optimal insertion angle and position for orthodontic mini-implants in the anterior palate. METHODS: Maxillary cone-beam computed tomographic (CBCT) scans from 30 patients (8 male, 22 female, age 18.6 ± 12.0 years) were analyzed. To assess the maximum possible length of an implant, a 25-reference-point grid was defined: 5 sagittal slices were extracted along the median plane and bilaterally at 3 mm and 6 mm distances, respectively. Within each slice, 5 dental reference points were projected to the palatal curvature at the contact point between the cuspid (C) and first bicuspid (PM1), midpoint of PM1, between PM1 and PM2, midpoint of PM2, and between PM2 and the first molar (M1). Measurements were conducted at -30°, -20°, -10°, 0°, 10°, 20°, and 30° to a vector placed perpendicular to the local palatal curvature. Statistical analysis was conducted with the use of R using a random-effects mixed linear model and a Tukey post hoc test with Holm correction. RESULTS: High interindividual variability was detected. Maximum effective bone heights were detected within a T-shaped area at the midpoint of PM1 and contact point PM1-PM2 (P < 0.01). Within the anterior region a posterior tipping was advantageous, whereas in the posterior regions an anterior tipping was beneficial (P < 0.01). In the middle of the median plane, tipping did not reveal a significant influence. No gender- or age-related differences were observed. CONCLUSIONS: Within the limitations of this study, optimal insertion positions were found within a T-shaped area at the height of PM1-PM2 in the anterior palate. In general, a posterior tipping was beneficial at anterior positions, and an anterior tipping appeared beneficial at posterior positions. High interindividual variation was found and should be carefully considered by the clinician.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Implantes Dentários , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Procedimentos de Ancoragem Ortodôntica/métodos , Palato/anatomia & histologia , Palato/diagnóstico por imagem , Adolescente , Adulto , Análise de Variância , Dente Pré-Molar , Parafusos Ósseos , Criança , Estudos Transversais , Dente Canino , Feminino , Humanos , Incisivo/anatomia & histologia , Incisivo/diagnóstico por imagem , Masculino , Maxila/cirurgia , Dente Molar , Osso Nasal/anatomia & histologia , Osso Nasal/diagnóstico por imagem , Procedimentos de Ancoragem Ortodôntica/instrumentação , Desenho de Aparelho Ortodôntico , Palato/cirurgia , Adulto Jovem
16.
Clin Oral Implants Res ; 30(12): 1179-1189, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31494964

RESUMO

OBJECTIVES: Whereas stationary stability of implants has been postulated for decades, recent studies suggested a phenomenon termed implant migration. This describes a change in position of implants as a reaction to applied forces. The present study aims at employing image registration of in vivo micro-CT scans from different time points and to assess (a) if migration of continuously loaded implants is possible and (b) migration correlates with the force magnitude. MATERIAL AND METHODS: Two customized machined implants were placed in the dorsal portion of caudal vertebrae in n = 61 rats and exposed to standardized forces (0.5 N, 1.0 N, and 1.5 N) applied through a flat nickel-titanium contraction spring, or no forces (control). Micro-CT scans were performed at 0, 1, 2, 4, 6, and 8 weeks after surgery. The baseline image was registered with the forthcoming scans. Implant migration was measured as the Euclidean distance between implant tips. Bone remodeling was assessed between the baseline and the forthcoming scans. RESULTS: The findings confirmed a positional change of the implants at 2 and 8 weeks of healing, and a linear association between applied force and velocity of movement (anterior implant: χ2  = 12.12, df = 3, and p = .007 and posterior implant: χ2  = 20.35, df = 3, and p < .001). Bone apposition was observed around the implants and accompanied by formation of load-bearing trabeculae and a general cortical thickening close and also distant to the implants. CONCLUSION: The present analysis confirmed that implants can migrate in bone. The applied forces seemed to stimulate bone thickening, which could explain why implants migrate without affecting stability.


Assuntos
Implantes Dentários , Animais , Remodelação Óssea , Osso e Ossos , Osseointegração , Ratos , Coluna Vertebral , Titânio , Microtomografia por Raio-X
17.
Ann Anat ; 226: 57-63, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31330307

RESUMO

BACKGROUND: Bone ageing is governed by the linked activities of short-lived osteoblasts and osteoclasts in conjunction with long-lived osteocytes present in osseous structure. Besides their maintenance function, osteogenic cells also gain specific positional information, which may potentially trigger ageing-associated cellular deviations in terminally differentiated osteocytes differently in cranial versus postcranial tissues. METHODS: We therefore investigated bone taken from deceased aged humans explanted at five distinct anatomical positions throughout the body and assessed physical and biological determinants applying radiologic and histologic measures. RESULTS: We were able to show that significantly more osteocytes reside in aged cortical bone at cranial positions than within axial or limb skeleton. These cellular states and conditions were not found in the corresponding trabecular bone, where osteocyte numbers remain also high at postcranial positions. Parallel comparative analyses of bone microstructure as analyzed by means of computer tomography showed no significant differences. CONCLUSIONS: Considering differences and commonalities regarding the bone samples, such as loading, mechanisms of ossification or the surrounding stromal cell compartment, our findings indicate that positional information laid down during ontogenetic processes is instructive during the entire life thus potentially also moulding spatial-specific mechanistic distinctions of bone ageing.


Assuntos
Envelhecimento/fisiologia , Osteócitos , Crânio/citologia , Crânio/crescimento & desenvolvimento , Idoso , Idoso de 80 Anos ou mais , Desenvolvimento Ósseo , Cadáver , Contagem de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Regeneração , Esqueleto , Células Estromais/ultraestrutura , Microtomografia por Raio-X
18.
Stem Cells Transl Med ; 8(10): 1084-1091, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31179644

RESUMO

Bone infections are a frequent cause for large bony defects with a reduced healing capacity. In previous findings, we could already show diminished healing capacity after bone infections, despite the absence of the causing agent, Staphylococcus aureus. Moreover, these bony defects showed reduced osteoblastogenesis and increased osteoclastogenesis, meaning elevated bone resorption ongoing with an elevated B-cell activity. To overcome the negative effects of this postinfectious inflammatory state, we tried to use the regenerative capacity of mesenchymal stem cells derived from adipose tissue (adipose-derived stem cells [ASCs]) to improve bone regeneration and moreover were curious about immunomodulation of applicated stem cells in this setting. Therefore, we used our established murine animal model and applicated ASCs locally after sufficient debridement of infected bones. Bone regeneration and resorption as well as immunological markers were investigated via histology, immunohistochemistry, Western blot, and fluorescence-activated cell scanning (FACS) analysis and µ-computed tomography (CT) analysis. Interestingly, ASCs were able to restore bone healing via elevation of osteoblastogenesis and downregulation of osteoclasts. Surprisingly, stem cells showed an impact on the innate immune system, downregulating B-cell population. In summary, these data provide a fascinating new and innovative approach, supporting bone healing after bacterial infections and moreover gain insights into the complex ceremony of stem cell interaction in terms of bone infection and regeneration. Stem Cells Translational Medicine 2019;8:1084-1091.


Assuntos
Tecido Adiposo/metabolismo , Linfócitos B/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteomielite/fisiopatologia , Tecido Adiposo/citologia , Animais , Diferenciação Celular , Feminino , Humanos , Masculino , Camundongos
19.
J Clin Periodontol ; 46(9): 969-976, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31241784

RESUMO

OBJECTIVES: To assess the short-term clinical outcomes of lateral alveolar ridge augmentation using autogenous tooth roots (TR) and autogenous bone blocks (AB). MATERIAL AND METHODS: A total of n = 23 patients (23 implants) were available for the analysis. Each subject was allocated to lateral ridge augmentation using either (a) healthy autogenous tooth roots (e.g., retained wisdom or impacted teeth; n = 13) or (b) cortical autogenous bone blocks harvested from the retromolar area (n = 10). Clinical parameters (e.g., bleeding on probing-BOP, probing pocket depth-PD, mucosal recession-MR, clinical attachment level-CAL) were recorded at (V8) and after 26 ± 4 weeks (V9) of implant loading. RESULTS: TR and AB groups were associated with comparable (p > 0.05) changes in mean BOP (-23.0 ± 34.3%; -11.75 ± 24.9%), PD (-0.03 ± 0.14 mm; -0.1 ± 0.29 mm), MR (0.0 ± 0.0 mm; 0.0 ± 0.0 mm) and CAL (-0.03 ± 0.14 mm; -0.1 ± 0.29 mm) values. The regression analysis failed to reveal any significant correlations between changes in BOP and PD values and the initial as well as the ridge width measured at 26 weeks. CONCLUSIONS: TR and AB were associated with comparable clinical short-term outcomes.


Assuntos
Aumento do Rebordo Alveolar , Dente Impactado , Transplante Ósseo , Implantação Dentária Endo-Óssea , Humanos , Estudos Prospectivos , Projetos de Pesquisa , Raiz Dentária
20.
Clin Oral Implants Res ; 30(5): 439-446, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30955205

RESUMO

OBJECTIVES: To assess the feasibility of using autogenous tooth roots (TR) for a lateral augmentation of deficient extraction sockets and two-stage implant placement. MATERIAL AND METHODS: A total of 15 patients were recruited to perform a simultaneous, lateral augmentation of deficient (i.e., thickness of the buccal bone < 0.5 mm or buccal dehiscence-type defects) fresh extraction sockets using the respective non-retainable but non-infected teeth (n = 15). After 26 weeks of submerged healing, the primary endpoint was defined as the crestal ridge width (mm) (CW26) being sufficient to place an adequately dimensioned titanium implant at the respective sites. RESULTS: The surgical procedure could be accomplished in n = 14 patients. Soft tissue healing was uneventful in all patients. CW26 at visit 6 allowed for a successful implant placement in all patients (e.g., 14/14). Mean CW26 values amounted to 10.85 ± 2.71 mm (median: 8.5). The change (4.89 ± 2.29 mm) in CW compared to baseline was statistically significant (p < 0.001). CONCLUSIONS: The usage of TR may represent a feasible approach for lateral augmentation of deficient extraction sockets and two-stage implant placement.


Assuntos
Aumento do Rebordo Alveolar , Alvéolo Dental , Humanos , Estudos Prospectivos , Extração Dentária , Raiz Dentária
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