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1.
Benef Microbes ; 12(1): 17-30, 2021 Feb 24.
Article in English | MEDLINE | ID: mdl-33350360

ABSTRACT

Faecal microbiota transfer (FMT) consists of the infusion of donor faecal material into the intestine of a patient with the aim to restore a disturbed gut microbiota. In this study, it was investigated whether FMT has an effect on faecal microbial composition, its functional capacity, faecal metabolite profiles and their interactions in 16 irritable bowel syndrome (IBS) patients. Faecal samples from eight different time points before and until six months after allogenic FMT (faecal material from a healthy donor) as well as autologous FMT (own faecal material) were analysed by 16S RNA gene amplicon sequencing and gas chromatography coupled to mass spectrometry (GS-MS). The results showed that the allogenic FMT resulted in alterations in the microbial composition that were detectable up to six months, whereas after autologous FMT this was not the case. Similar results were found for the functional profiles, which were predicted from the phylogenetic sequencing data. While both allogenic FMT as well as autologous FMT did not have an effect on the faecal metabolites measured in this study, correlations between the microbial composition and the metabolites showed that the microbe-metabolite interactions seemed to be disrupted after allogenic FMT compared to autologous FMT. This shows that FMT can lead to altered interactions between the gut microbiota and its metabolites in IBS patients. Further research should investigate if and how this affects efficacy of FMT treatments.


Subject(s)
Bacteria/metabolism , Fecal Microbiota Transplantation , Irritable Bowel Syndrome/metabolism , Irritable Bowel Syndrome/therapy , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Feces/chemistry , Feces/microbiology , Gastrointestinal Microbiome , Humans , Irritable Bowel Syndrome/microbiology , Phylogeny , Treatment Outcome
2.
Sci Rep ; 8(1): 13404, 2018 09 07.
Article in English | MEDLINE | ID: mdl-30194322

ABSTRACT

Gastrointestinal problems are common in elderly and often associated with psychological distress and increased levels of corticotrophin-releasing hormone, a hormone known to cause mast cell (MC) degranulation and perturbed intestinal barrier function. We investigated if dietary fibres (non-digestible polysaccharides [NPS]) could attenuate MC-induced colonic hyperpermeability in elderly with gastrointestinal (GI) symptoms. Colonic biopsies from elderly with diarrhoea and/or constipation (n = 18) and healthy controls (n = 19) were mounted in Ussing chambers and pre-stimulated with a yeast-derived beta (ß)-glucan (0.5 mg/ml) or wheat-derived arabinoxylan (0.1 mg/ml) before the addition of the MC-degranulator Compound (C) 48/80 (10 ng/ml). Permeability markers were compared pre and post exposure to C48/80 in both groups and revealed higher baseline permeability in elderly with GI symptoms. ß-glucan significantly attenuated C48/80-induced hyperpermeability in elderly with GI symptoms but not in healthy controls. Arabinoxylan reduced MC-induced paracellular and transcellular hyperpermeability across the colonic mucosa of healthy controls, but did only attenuate transcellular permeability in elderly with GI symptoms. Our novel findings indicate that NPS affect the intestinal barrier differently depending on the presence of GI symptoms and could be important in the treatment of moderate constipation and/or diarrhoea in elderly.


Subject(s)
Colon/metabolism , Constipation/metabolism , Diarrhea/metabolism , Dietary Fiber/pharmacology , Intestinal Absorption , Xylans , Adrenocorticotropic Hormone/metabolism , Adult , Aged , Biopsy , Cell Degranulation/drug effects , Colon/pathology , Colon/physiopathology , Constipation/pathology , Constipation/physiopathology , Diarrhea/pathology , Diarrhea/physiopathology , Female , Humans , Male , Mast Cells/metabolism , Mast Cells/pathology , Permeability/drug effects , Stress, Psychological/metabolism , Stress, Psychological/pathology , Stress, Psychological/physiopathology , Xylans/pharmacokinetics , Xylans/pharmacology
3.
J Hum Nutr Diet ; 30(3): 284-291, 2017 06.
Article in English | MEDLINE | ID: mdl-27709718

ABSTRACT

BACKGROUND: It is challenging to identify malnutrition, which is a risk factor for poor outcome in patients with liver cirrhosis. In the present study, we aimed to investigate the prevalence of malnutrition among patients listed for liver transplantation, as assessed by different methods, and also to relate dual-energy X-ray absorptiometry (DXA) to short-term post-transplant outcomes. METHODS: In this retrospective cohort study, we reviewed the medical records of 106 patients who underwent liver transplantation in 2009-2012. Body composition was assessed by the fat-free mass index (FFMI) and fat mass index (FMI) obtained using DXA. Severe infections within 1 month, length of stay in intensive care unit and length of hospital stay were endpoints of primary interest. RESULTS: The prevalence of malnutrition was 2-20% depending on sex and the assessment method. Thirty-nine (37%) patients developed severe infections within 1 month after liver transplantation. In multivariate analysis with logistic regression, body composition was significantly associated with post-operative infection when measured with FFMI (P = 0.043) but not with FMI (P = 0.087). Post-operative dialysis (P = 0.004) and post-operative infections (P < 0.001) were significantly associated with length of stay in hospital. Post-operative bleeding (P = 0.015), duration of mechanical ventilation (P < 0.001) and the need for dialysis (P < 0.001), but not body composition, were significant predictors of the length of stay in the intensive care unit. CONCLUSIONS: The prevalence of malnutrition depends on assessment method. FFMI is an independent predictor for early post-transplant infections. Body composition measured by DXA during the pretransplant evaluation provides valuable information about nutritional status in patients with liver cirrhosis.


Subject(s)
Absorptiometry, Photon , Body Composition , Communicable Diseases/epidemiology , Liver Transplantation/adverse effects , Malnutrition/epidemiology , Postoperative Complications/epidemiology , Adult , Aged , Communicable Diseases/etiology , Endpoint Determination , Female , Humans , Length of Stay , Logistic Models , Male , Malnutrition/diagnosis , Malnutrition/etiology , Middle Aged , Nutrition Assessment , Nutritional Status , Postoperative Complications/etiology , Postoperative Complications/microbiology , Prevalence , Retrospective Studies , Risk Factors
4.
Oncotarget ; 7(39): 64071-64088, 2016 Sep 27.
Article in English | MEDLINE | ID: mdl-27590521

ABSTRACT

To characterize the mutational patterns of acute lymphoblastic leukemia (ALL) we performed deep next generation sequencing of 872 cancer genes in 172 diagnostic and 24 relapse samples from 172 pediatric ALL patients. We found an overall greater mutational burden and more driver mutations in T-cell ALL (T-ALL) patients compared to B-cell precursor ALL (BCP-ALL) patients. In addition, the majority of the mutations in T-ALL had occurred in the original leukemic clone, while most of the mutations in BCP-ALL were subclonal. BCP-ALL patients carrying any of the recurrent translocations ETV6-RUNX1, BCR-ABL or TCF3-PBX1 harbored few mutations in driver genes compared to other BCP-ALL patients. Specifically in BCP-ALL, we identified ATRX as a novel putative driver gene and uncovered an association between somatic mutations in the Notch signaling pathway at ALL diagnosis and increased risk of relapse. Furthermore, we identified EP300, ARID1A and SH2B3 as relapse-associated genes. The genes highlighted in our study were frequently involved in epigenetic regulation, associated with germline susceptibility to ALL, and present in minor subclones at diagnosis that became dominant at relapse. We observed a high degree of clonal heterogeneity and evolution between diagnosis and relapse in both BCP-ALL and T-ALL, which could have implications for the treatment efficiency.


Subject(s)
High-Throughput Nucleotide Sequencing , Mutation , Neoplasm Recurrence, Local/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Adaptor Proteins, Signal Transducing , Child , Child, Preschool , Cohort Studies , DNA Mutational Analysis , DNA-Binding Proteins , E1A-Associated p300 Protein/genetics , Epigenesis, Genetic , Humans , Immunophenotyping , Infant , Intracellular Signaling Peptides and Proteins , Nuclear Proteins/genetics , Oncogene Proteins, Fusion/genetics , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Proteins/genetics , Recurrence , Remission Induction , Sequence Analysis, DNA , Transcription Factors/genetics , Translocation, Genetic
5.
Clin Oral Investig ; 17(1): 113-21, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22415217

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate clinical and radiological findings and the role of periapical infection and antecedent dental treatment of infected focus teeth in odontogenic maxillofacial abscesses requiring hospital care. MATERIALS AND METHODS: In this retrospective cohort study, we evaluated medical records and panoramic radiographs during the hospital stay of patients (n = 60) admitted due to odontogenic maxillofacial infection originating from periapical periodontitis. RESULTS: Twenty-three (38 %) patients had received endodontic treatment and ten (17 %) other acute dental treatment. Twenty-seven (45 %) had not visited the dentist in the near past. Median age of the patients was 45 (range 20-88) years and 60 % were males. Unfinished root canal treatment (RCT) was the major risk factor for hospitalisation in 16 (27 %) of the 60 cases (p = .0065). Completed RCT was the source only in 7 (12 %) of the 60 cases. Two of these RCTs were adequate and five inadequate. CONCLUSIONS: The initiation of inadequate or incomplete primary RCT of acute periapical periodontitis appears to open a risk window for locally invasive spread of infection with local abscess formation and systemic symptoms. Thereafter, the quality of the completed RCT appears to have minor impact. However, a considerable proportion of the patients had not received any dental treatment confirming the importance of good dental health. Thus, thorough canal debridement during the first session is essential for minimising the risk for spread of infection in addition to incision and drainage of the abscess. If this cannot be achieved, tooth extraction should be considered. CLINICAL RELEVANCE: Incomplete or inadequate canal debridement and drainage of the abscess may increase the risk for spread of endodontic infection.


Subject(s)
Focal Infection, Dental/complications , Hospitalization , Periapical Periodontitis/complications , Root Canal Therapy/methods , Abscess/etiology , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/therapeutic use , Cellulitis/etiology , Cohort Studies , Disease Progression , Drainage , Female , Focal Infection, Dental/microbiology , Follow-Up Studies , Glossitis/etiology , Humans , Length of Stay , Male , Middle Aged , Mouth Diseases/etiology , Periapical Abscess/etiology , Periapical Periodontitis/microbiology , Pulpectomy , Retreatment , Retrospective Studies , Risk Factors , Root Canal Therapy/adverse effects , Tooth Extraction , Young Adult
6.
J Fish Biol ; 78(6): 1861-7, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21651534

ABSTRACT

Broad-nosed pipefish Syngnathus typhle were used to investigate whether males used scent in their search for mates. When the males in an experiment had access to olfactory cues only, they did not locate females better than they located males. Thus, S. typhle, was less successful in mate search when visual cues were absent.


Subject(s)
Sexual Behavior, Animal , Smegmamorpha/physiology , Smell , Animals , Choice Behavior , Cues , Female , Male
7.
Int J Oral Maxillofac Surg ; 39(8): 774-8, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20435438

ABSTRACT

The aim of this retrospective study was to clarify the occurrence and types of dental injuries in 389 patients who had been diagnosed with facial fractures, and to analyze whether the occurrence of dental injury correlates to gender, age, trauma mechanism and type of facial fracture. Dental injuries were observed in 62 patients (16%). The most common type of injury was a crown fracture (48%). Dental injuries were multiple in most patients (63%). Almost half (48%) of all injured teeth were severely injured. Most injured teeth (61%) were in the maxilla. The incisor region was the most prevalent site in both the mandible (45%) and the maxilla (56%). The occurrence of dental injury correlated significantly with trauma mechanism and fracture type: motor vehicle accidents and mandibular fracture were significant predictors for dental trauma. The notable rate of dental injury observed in the present study emphasizes the importance of a thorough examination of the oral cavity in all patients who have sustained facial fracture. Referral to a dental practice for further treatment and follow up as soon as possible after discharge from hospital is fundamental.


Subject(s)
Facial Bones/injuries , Fractures, Bone/epidemiology , Maxillofacial Injuries/epidemiology , Tooth Fractures/epidemiology , Tooth Injuries/epidemiology , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Child , Comorbidity , Female , Finland/epidemiology , Humans , Male , Middle Aged , Sex Distribution , Young Adult
8.
Int J Oral Maxillofac Surg ; 39(5): 430-5, 2010 May.
Article in English | MEDLINE | ID: mdl-20181459

ABSTRACT

Removal of miniplates is a controversial topic in oral and maxillofacial surgery. Originally, miniplates were designed to be removed on completion of bone healing. The introduction of low profile titanium miniplates has led to the routine removal of miniplates becoming comparatively rare in many parts of the world. Few studies have investigated the reasons for non-routine removal of miniplates and the factors that affect osteosynthesis after osteotomy in large numbers of patients. The aim of the present study was to investigate complications related to osteosynthesis after bilateral sagittal split osteotomy (BSSO) in a large number (n=153) of patients. In addition to the rates of removal, emphasis was placed on investigating the reasons and risk factors associated with symptomatic miniplate removal. The rate of plate removal per patient was 18.6%, the corresponding rate per plate being 18.2%. Reasons for plate removal included plate-related complications in 16 patients and subjective discomfort in 13 patients. Half of the plates were removed during the first postoperative year. Smoking was the only significant predictor for plate removal. Patients undergoing orthognathic surgery should be screened with regard to smoking and encouraged and assisted to cease smoking, at least perioperatively.


Subject(s)
Bone Plates/adverse effects , Device Removal , Jaw Fixation Techniques/instrumentation , Mandible/surgery , Orthognathic Surgical Procedures/instrumentation , Smoking/adverse effects , Adolescent , Adult , Bone Plates/psychology , Chi-Square Distribution , Equipment Failure , Female , Humans , Logistic Models , Male , Middle Aged , Osteotomy/instrumentation , Retrospective Studies , Risk Factors , Surgical Wound Infection/etiology , Surgical Wound Infection/surgery , Titanium , Young Adult
9.
Cancer Gene Ther ; 16(11): 848-60, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19461675

ABSTRACT

CD40, a tumor necrosis factor receptor family member, is an emerging target for cancer therapy being best appreciated as an important regulator of the anti-tumor immune response. In this study, we report the development of a replication-defective recombinant adenovirus (RAd) vector expressing human CD40 ligand (RAd-hCD40L) and show that sustained engagement of the CD40 pathway in malignant cells results in direct anti-proliferative and pro-apoptotic effects. Thus, transduction of CD40-positive bladder, cervical and ovarian carcinoma cell lines with RAd-hCD40L potently inhibits their proliferation in vitro, whereas CD40-negative lines remain unresponsive. RAd-hCD40L is also found to be superior to recombinant CD40L in inducing carcinoma cell death and in amplifying the cytotoxic effects of the chemotherapeutic agents 5-fluorouracil, cis-platin and mitomycin C. Soluble CD40L is produced by RAd-hCD40L transduced carcinoma cells but unlike other soluble tumor necrosis factor family ligands, it does not interfere with the death-promoting activity of its membrane-bound form. In a mouse xenograft tumor model bearing a human bladder carcinoma, intratumoral delivery of RAd-hCD40L suppresses cancer growth. These findings highlight the potential of exploiting the CD40 pathway in carcinomas using CD40L gene transfer alone or in combination with other modalities for cancer therapy. Our results have also broader implications in understanding the multifaceted anti-tumor activities of the CD40 pathway in carcinomas, which thus offer an attractive option for future clinical application.


Subject(s)
Adenoviridae/genetics , CD40 Ligand/genetics , CD40 Ligand/metabolism , CD40 Ligand/physiology , Carcinoma/therapy , Genetic Therapy/methods , Animals , Antineoplastic Agents/therapeutic use , Apoptosis/physiology , Cell Line, Tumor , Cell Proliferation/drug effects , Cisplatin/therapeutic use , Flow Cytometry , Fluorouracil/therapeutic use , Humans , Immunoblotting , Mice , Mice, Nude , Mitomycin/therapeutic use , Xenograft Model Antitumor Assays
10.
Int J Oral Maxillofac Surg ; 38(3): 201-9, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19168327

ABSTRACT

Microvascular reconstruction is the state-of-the-art in many fields of defect surgery today. Currently, reconstruction of large bony defects involves harvesting of autologous bone causing donor site morbidity and risk of infection. Specifically, utilizing autologous adipose stem cells (autoASCs), large quantities of cells can be retrieved for cell therapy applications and the risk of tissue rejection is diminished. The authors describe the first case report of a microvascular custom-made ectopic bone flap employing good manufacturing practice (GMP) level ASCs. The patient underwent a hemimaxillectomy due to a large keratocyst. After 36 months of follow-up, the defect was reconstructed with a microvascular flap using autoASCs, beta-tricalcium phosphate and bone morphogenetic protein-2. ASCs were isolated and expanded in clean room facilities according to GMP standards and were characterized in vitro. After 8 months of follow-up, the flap had developed mature bone structures and vasculature and was transplanted into the defect area. Postoperative healing has been uneventful, and further rehabilitation with dental implants has been started. The in vitro characterization demonstrated multipotentiality and mesenchymal stem cell characteristics in ASCs. This is the first clinical case where ectopic bone was produced using autoASCs in microvascular reconstruction surgery and it will pave way for new clinical trials in the field.


Subject(s)
Adipose Tissue/cytology , Adult Stem Cells/cytology , Maxillary Diseases/surgery , Plastic Surgery Procedures/methods , Surgical Flaps/physiology , Tissue Engineering/methods , Abdominal Fat/cytology , Aged , Bone Morphogenetic Protein 2/physiology , Bone Substitutes/pharmacology , Bone and Bones/cytology , Bone and Bones/physiology , Calcium Phosphates/pharmacology , Cell Differentiation/physiology , Humans , Male , Maxillary Diseases/complications , Microvessels/physiology , Multipotent Stem Cells/cytology , Odontogenic Cysts/complications , Odontogenic Cysts/surgery , Oral Surgical Procedures/methods , Ossification, Heterotopic/chemically induced , Osteocytes/cytology , Osteogenesis/physiology , Prostheses and Implants , Treatment Outcome
11.
Int J Oral Maxillofac Surg ; 37(12): 1080-8, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18672348

ABSTRACT

This study evaluates a comprehensive classification system for mandibular fractures based on imaging analysis. The AO/ASIF scheme, defining three fracture types (A, B, C), three groups within each type (e.g. A1, A2, A3) and three subgroups within each group (e.g. A1.1, A1.2, A1.3) with increasing severity from A1.1 (lowest) to C3.3 (highest) was used. The mandible is divided into two vertical units (I and V), two lateral horizontal units (II and IV) and one central unit (III) comprising the symphyseal and parasymphyseal region. Type A fractures are non-displaced, type B are displaced and type C are multifragmentary/defect injuries. Groups and subgroups are further defined in the classification system. Two classification sessions using semi-automatic software with 7 and 9 surgeons were performed to evaluate 100 fracture cases in the first session and 50 in the second. Inter-observer reliability and individual rater's accuracy were evaluated by kappa coefficient and latent class analysis, respectively. The analysis of inter-observer agreement for the detailed coding showed kappa coefficients around 0.50 with higher agreement among raters in the vertical units. This system allows standardization of documentation of mandibular fractures, although improvement in the definition of categories and their application is required.


Subject(s)
Mandibular Fractures/classification , Dental Arch/injuries , Humans , Image Processing, Computer-Assisted/methods , Joint Dislocations/classification , Mandible/anatomy & histology , Mandibular Condyle/injuries , Mandibular Fractures/diagnostic imaging , Observer Variation , Radiography, Panoramic/methods , Software , Tomography, X-Ray Computed/methods , Tooth Injuries/classification
12.
J Biomed Mater Res A ; 83(2): 530-7, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17508414

ABSTRACT

The aim of this study was to evaluate rabbit soft tissue reactions to bioactive glass 13-93 mesh by using a histological and immunohistochemical analysis. Bioactive glass (13-93) mesh fixed with 3 wt % chitosan was implanted into the dorsal subcutaneous space of New Zealand White rabbits (n=18) for six, 12, and 24 weeks, respectively. After 6 weeks the bioactive glass remnants were surrounded by foreign-body granuloma with eosinophilic granulocytes. After 12 and 24 weeks the implanted material was mainly absorbed, but, if any particles still remained the foreign-body reaction was notably milder. Yet, a mild chronic inflammatory infiltrate was present. Matrix metalloproteinase (MMP) -2, -3, -13 and tissue inhibitory protein (TIMP-1 and -2) expressions were studied by immunohistochemistry. MMP-3, -13, TIMP-1, and -2 positivity were detected throughout the follow-up period. MMP-2 positivity was only occasionally seen in the 24 week samples, which is constitutively expressed but is not related to inductive MMP-3 and -13 cascade. The presence of eosinophilic granulocytes in some of the samples raises the possibility of an allergic reaction to the materials. MMP-3 and -13 are suggested to participate in the host reaction to either bioactive glass or chitosan.


Subject(s)
Chitosan/metabolism , Foreign-Body Reaction , Glass , Skin/metabolism , Animals , Endothelial Cells/cytology , Endothelial Cells/enzymology , Female , Immunohistochemistry , Materials Testing , Matrix Metalloproteinase 13/metabolism , Prosthesis Implantation , Rabbits , Skin/cytology
13.
Int J Oral Maxillofac Surg ; 35(11): 983-9, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17052893

ABSTRACT

The aim of this study was to investigate the condition of the temporomandibular joint (TMJ) in patients with different rheumatic diseases, and report correlations between the clinical, radiographic and magnetic resonance imaging (MRI) findings. The 67 patients were divided into four groups: 16 with rheumatoid arthritis (RA), 15 with mixed connective tissue disease (MCTD), 18 with ankylosing spondylitis (AS) and 18 with spondyloarthropathy (SPA). They were clinically examined, and panoramic tomography, lateral panoramic radiography and MRI of the TMJ were performed. MRI showed reduced articular cartilage in 25% (4/16) of RA, 0% (0/15) of MCTD, 17% (3/18) of AS and 17% (3/18) of SPA patients. Condylar changes included erosion, osteophytes and abnormal shape. Disc alterations included perforation, abnormal anterior position and decreased movement. These abnormalities were most frequent in RA patients, and least frequent in MCTD and SPA patients. Crepitation and reduced maximum opening of the mouth correlated with abnormalities of the disc and articular cartilage as shown by MRI. Severe condylar erosion in panoramic tomograms significantly correlated with MRI findings of condylar erosion (P<0.01), diminished thickness of condylar cartilage, abnormal condylar shape, and abnormal shape of the temporal surface of the TMJ (P< or =0.001). The presence of crepitation, limited mandibular movement and/or pain on movement of the jaw often indicated structural damage to the TMJ. Panoramic radiographs provide an alternative method to MRI but, to obtain a more detailed anatomic picture, MRI is recommended for patients with acute unexplained pain or as part of preoperative work up. A panoramic recording is not indicated when MRI is planned.


Subject(s)
Mixed Connective Tissue Disease/complications , Rheumatic Diseases , Temporomandibular Joint , Adult , Arthritis, Rheumatoid/diagnostic imaging , Arthritis, Rheumatoid/pathology , Epidemiologic Methods , Female , Humans , Magnetic Resonance Imaging , Male , Mandibular Condyle/diagnostic imaging , Mandibular Condyle/pathology , Middle Aged , Mixed Connective Tissue Disease/diagnostic imaging , Radiography , Rheumatic Diseases/diagnostic imaging , Rheumatic Diseases/pathology , Spondylarthropathies/diagnostic imaging , Spondylarthropathies/pathology , Spondylitis, Ankylosing/diagnostic imaging , Spondylitis, Ankylosing/pathology , Temporomandibular Joint/diagnostic imaging , Temporomandibular Joint/pathology , Temporomandibular Joint Disc/diagnostic imaging , Temporomandibular Joint Disc/pathology
14.
Int J Oral Maxillofac Surg ; 35(7): 631-5, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16540288

ABSTRACT

In many cases only the temporary presence of a biomaterial is needed in tissue support, augmentation or replacement. In such cases biodegradable materials are better alternatives than biostable ones. At present, biodegradable polymers are widely used in the field of maxillofacial surgery as sutures, fracture fixation devices and as absorbable membranes. The most often used polymers are aliphatic polyesters, such as polyglycolic acid (PGA) and polylactic acid (PLA). Poly(ortho ester) is a surface eroding polymer, which has been under development since 1970, but is used mostly in drug delivery systems in semisolid form. The aim of this study was to evaluate the tissue reactions of solid poly(ortho ester) (POE), histologically and immunohistochemically. Resorption times and the effect of 2 different sterilization methods (gamma radiation and ethylene oxide) upon resorption were also evaluated. Material was implanted into the tibia and subcutaneously into the mandibular ramus area of 24 rabbits. Follow-up times were 1-10, 14 and 24 weeks. Histological studies showed that POE induces a moderate inflammation in soft tissue and in bone. At 24 week follow-up, inflammation was mild in soft tissue and moderate in bone. In immunohistochemical studies, no highly fluorescent layer of tenascin or fibronectin was found adjacent to the implant. Resorption of gamma-sterilized rods was faster than ethylene oxide-sterilized rods. The total resorption time was more than 24 weeks in both groups. Clinically the healing was uneventful and the implants the well tolerated by the living tissue. This encourages these authors to continue studies with this interesting new material to search for the ideal material for bone filling and fracture fixation.


Subject(s)
Absorbable Implants/adverse effects , Bone Substitutes/toxicity , Foreign-Body Reaction/etiology , Polymers/toxicity , Animals , Connective Tissue/drug effects , Connective Tissue/surgery , Ethylene Oxide/pharmacology , Female , Fibronectins/analysis , Gamma Rays , Immunohistochemistry , Mandible/drug effects , Mandible/surgery , Rabbits , Sterilization/methods , Tenascin/analysis , Tibia/drug effects , Tibia/surgery
15.
J Mater Sci Mater Med ; 17(2): 139-45, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16502246

ABSTRACT

In the field of craniomaxillofacial and orthopaedic surgery there is a constant need for bone or bone substitute. At the present, the most effective way to enhance bone healing clinically is to use autogenous bone grafts. The problems associated with the use of these autografts are donor site morbidity, limited supply and need for a second operative site. Currently there are several different synthetic products commercially available in the market; nevertheless, none of them is ideal for filling bone defects. Therefore, search for new synthetic materials for bone replacement is necessary. A mixture of tricalcium phosphate (TCP) and epsilon-caprolactone-lactide copolymer P(epsilon -CL/DL-LA) was prepared and implanted in critical size mandibular bone defects in twelve sheep. Contralateral side was used as a control. Follow-up times for histological and radiological studies were 9, 14, 24 and 52 weeks. We found that the implanted material did not enhance bone formation compared to control site. We also confirmed that defect size was of critical size, since there was no complete healing of the control site either. The results do not encourage us to continue our studies with the mixture of TCP and P(epsilon-CL/DL-LA) as a filling material for bone defects. Therefore the search for the ideal material is still ongoing.


Subject(s)
Bone Substitutes/chemistry , Bone and Bones/drug effects , Calcium Phosphates/chemistry , Mandible/metabolism , Mandibular Diseases/therapy , Polyesters/chemistry , Polymers/chemistry , Animals , Binding Sites , Bone Development , Bone Regeneration , Bone and Bones/metabolism , Calcium Phosphates/metabolism , Disease Models, Animal , Inflammation , Osteoblasts/metabolism , Sheep , Time Factors
16.
Int J Oral Maxillofac Surg ; 34(7): 766-76, 2005 Oct.
Article in English | MEDLINE | ID: mdl-15979853

ABSTRACT

Several implants for orbital wall fracture treatment are available at the present, but they have drawbacks: resorption, risk for migration and foreign body reaction. Alloplastic resorbable implants would be advantageous: no removal operation and no donor side morbidity. The purpose of this study was to evaluate the foreign body reaction, capsule formation and mechanical properties of two bioresorbable implants. PDS and SR-P(L/DL)LA mesh sheet (70/30) with solid frame (96/4) implants (SR-P(L/DL)LA 70,96) were placed into subcutaneous tissue of 24 rats. Immunohistochemistry was used to evaluate reactivity for Tn-C, alpha-actin, type I and III collagens and two mononuclear cells: T-cells and monocyte/ macrophage. GPC, DSC and SEM were performed. Student's t-test or nonparametric Kruskall-Wallis test were used for statistical analysis. Histology of peri-implant capsule exhibited an inner cell-rich zone and an outer connective tissue zone around both materials. Tn-C reactivity was high in the inner and alpha-actin in the outer zone. At the end of the study, the difference of type I collagen versus type III collagen reactivity in inner zone was statistically significant (P<0.0001) as was the difference of type I collagen versus type III collagen reactivity in outer zone (P<0.0001). Immunohistochemistry did not reveal any statistical differences of T-cell and monocyte/macrophage reactivity around PDS versus SR-P(L/DL)LA 70,96 implants, nor any differences as a function of time. PDS were deformed totally after 2 months. SR-P(L/DL)LA 70,96 implants were only slightly deformed during the follow up of 7 months. PDS degraded rapidly in SEM observation. Particles were detaching from surface. SEM observation revealed that polylactide implant was degrading from the surface and the inner porous core became visible. The degradation came visible at 7 months. There were cracks in perpendicular direction towards to the long axis of the filaments. M(w) of PDS decreased fast compared to the polylactide implant. Foreign body reaction was minimal to both materials but continued throughout the whole observation period. Mechanically PDS was poor, it looses its shape totally within 2 months. It cannot be recommended for orbital wall reconstruction. New mesh sheet-frame structure (SR-P(L/DL)LA 70,96) approved to be mechanically adequate for orbital wall reconstruction. It seems not to possess intrinsic memory and retains its shape. The resorption time is significantly longer compared to PDS and is comparable to other studied P(L/DL)LA copolymers. Thus, the new polylactide copolymer implant may support the orbital contents long enough to give way to bone growth over the wall defect.


Subject(s)
Absorbable Implants , Orbital Implants , Polydioxanone , Polyesters , Absorbable Implants/adverse effects , Animals , Biocompatible Materials , Calorimetry, Differential Scanning , Chromatography, Gel , Connective Tissue/chemistry , Connective Tissue/metabolism , Foreign-Body Reaction/etiology , Immunohistochemistry , Male , Materials Testing , Microscopy, Electron, Scanning , Orbital Implants/adverse effects , Polydioxanone/adverse effects , Rats , Rats, Inbred Strains
17.
J Mater Sci Mater Med ; 16(8): 753-8, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15965746

ABSTRACT

Standardized bilateral through-and-through defects (12x6 mm) were created extraorally in the mandibular angle of 18 New Zealand White rabbits. Animals were divided in to three groups (n=6) according to the intended healing time. On the left side, defects were covered with a poly(desaminotyrosyl-tyrosine-ethyl ester carbonate) (PDTE carbonate) membrane wrapped around the inferior border of the mandible and fixed with bioabsorbable sutures. On the right side, the defects were filled with a mesh made of bioactive glass 13-93 and 3 wt% chitosan. The defects were covered with the same membranes. Periosteal flap was sutured over the membrane. Radiographically, bone ingrowth was seen in all specimens at 12 weeks postoperatively. At 24 weeks, completely ossified area remained approximately at the same level as at 12 weeks, but the non-ossified area decreased to almost zero. However, the bioactive glass mesh did not improve the results. Nevertheless, enveloping the defect with PDTE carbonate membrane seemed to play a crucial role in new bone formation. Based on these results, we conclude that tyrosine polycarbonate is a promising new material for guided bone regeneration.


Subject(s)
Biocompatible Materials/chemistry , Biopolymers/chemistry , Bone Regeneration/physiology , Guided Tissue Regeneration/methods , Implants, Experimental , Mandibular Diseases/diagnostic imaging , Mandibular Diseases/surgery , Membranes, Artificial , Tyrosine/analogs & derivatives , Animals , Biopolymers/analysis , Biopolymers/therapeutic use , Female , Materials Testing , Rabbits , Radiography , Surgery, Oral/methods , Treatment Outcome , Tyrosine/analysis , Tyrosine/chemistry , Tyrosine/therapeutic use , Wound Healing/physiology
18.
Int J Oral Maxillofac Surg ; 33(3): 240-4, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15287306

ABSTRACT

Bioabsorbable fixation devices have been used in our departments between November 1991 and November 2001 in orthognathic surgery. The aim of this retrospective study was to assess all complications experienced during this time period, when we have operated 163 patients who have undergone 329 orthognathic osteotomies fixated with bioresorbable devices. No postoperative intermaxillary fixation was used. Light guiding elastics were used for 5 to 7 weeks. Patients' acceptance was generally excellent and very few complications occurred during this follow-up of 10 years. The complications were minor and did not affect the end results of the operations. Minor complications occurred in 14 patients (8.6%). Only one patient (0.6%) had a postoperative infection with elevated infection parameters. The other minor complications consisted mainly of dehiscence of the wound and plate exposure together with granulation tissue in the operation field. The rest of the complications occurred in the beginning of our study, when large screw heads on top of the bone irritated the patient and had to be removed. Insufficient fixation resulted in open bite in three patients (1.8%) in the beginning of the trial use of new devices, which no longer are used. Based on our experience, bioresorbable devices are safe to be used in orthognathic procedures. However, there is a learning curve, as there is with all new methods introduced.


Subject(s)
Absorbable Implants/adverse effects , Bone Plates/adverse effects , Bone Screws/adverse effects , Mandible/surgery , Maxilla/surgery , Adolescent , Adult , Biocompatible Materials/chemistry , Female , Follow-Up Studies , Granulation Tissue/pathology , Humans , Male , Middle Aged , Open Bite/etiology , Osteotomy/instrumentation , Patient Satisfaction , Polyesters/chemistry , Retrospective Studies , Surgical Wound Dehiscence/etiology , Surgical Wound Infection/etiology
19.
Int J Oral Maxillofac Surg ; 33(4): 356-60, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15145038

ABSTRACT

Our aim was to investigate the occurrence of bacteremia associated with removal of a semirigid osteosynthesis plate and an adjacent third molar. Ten patients with fixed mandibular angle fracture were bacteriologically sampled from the second molar's distal gingival pocket, from the third molar's extraction socket and from the osteosynthesis plate. Blood samples from the ante-cubital vein were taken 10 times until 30 min postoperatively. Established culture, isolation and identification methods for the bacterial species were used. Bacteremia was detected in 60% of the subjects, most frequently 1.5 min after removal of the plate (20%) and 1.5 and 5 min after extraction of the tooth (20%), but also 10 min (10%) and 30 min (10%) postoperatively. 13 different bacterial species or groups were isolated, mean 2.5 +/- 1.9 per bacteremia-positive subject. The majority (85%) were anaerobes with Actinomyces, Campylobacter and Lactobacillus species predominating. In all the blood culture-positive cases the corresponding species was also recovered from one or more of the oral samples. These results show that oral surgical procedures are associated with a high frequency of longstanding anaerobic bacteremia, which could be harmful in patients at risk.


Subject(s)
Bacteremia/etiology , Device Removal/adverse effects , Mandibular Fractures/surgery , Tooth Extraction/adverse effects , Adult , Bacteria, Anaerobic/isolation & purification , Bone Plates , Female , Fracture Fixation, Internal , Humans , Jaw Fixation Techniques , Male , Molar, Third/surgery
20.
Int J Oral Maxillofac Surg ; 33(4): 361-8, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15145039

ABSTRACT

In this study the reconstruction capacity of orbital wall in sheep was evaluated when poly-L/D-lactide (PLDLA96) implants were used for large blow-out defects in 18 sheep. The contralateral side, where the defects healed spontaneously, served as controls. The follow-up was 12, 16, 22 and 36 weeks. Healing was evaluated clinically, radiologically, histologically and immunohistochemically. Physiochemical properties of the implants were also studied. At first, the implants were surrounded by elastic capsules, which gradually ossified. At 36 weeks, 60% were still visible and deformed but surrounded by bone. Light microscopy revealed a low grade inflammatory reaction. Expression of Tn-c and cFn was intense throughout the study. Shear strength decreased gradually and was not measurable after 16 weeks. Crystallinity increased steadily from 1.5 to 29.30% and molecular weight decreased from 49,000 to 4186. In CT, the final bony defect was smaller in the reconstructed sides than in the controls. Based on this study it can be concluded that PLDLA96 implant provokes a local inflammation, which does not prevent bone healing. The deformation of the implant, however, indicates that this PLDLA96 plate is not suitable for orbital floor reconstruction.


Subject(s)
Absorbable Implants , Orbital Fractures/surgery , Orbital Implants , Animals , Fibronectins/biosynthesis , Histocytochemistry , Implants, Experimental , Materials Testing , Orbital Fractures/diagnostic imaging , Orbital Fractures/metabolism , Polyesters , Radiography , Shear Strength , Sheep , Sheep, Domestic , Tenascin/biosynthesis , Viscosity
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