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1.
BMC Psychiatry ; 20(1): 458, 2020 09 22.
Article in English | MEDLINE | ID: mdl-32962684

ABSTRACT

BACKGROUND: Promoting well-being and preventing poor mental health in young people is a major global priority. Building emotional competence (EC) skills via a mobile app may be an effective, scalable and acceptable way to do this. However, few large-scale controlled trials have examined the efficacy of mobile apps in promoting mental health in young people; none have tailored the app to individual profiles. METHOD/DESIGN: The Emotional Competence for Well-Being in Young Adults cohort multiple randomised controlled trial (cmRCT) involves a longitudinal prospective cohort to examine well-being, mental health and EC in 16-22 year olds across 12 months. Within the cohort, eligible participants are entered to either the PREVENT trial (if selected EC scores at baseline within worst-performing quartile) or to the PROMOTE trial (if selected EC scores not within worst-performing quartile). In both trials, participants are randomised (i) to continue with usual practice, repeated assessments and a self-monitoring app; (ii) to additionally receive generic cognitive-behavioural therapy self-help in app; (iii) to additionally receive personalised EC self-help in app. In total, 2142 participants aged 16 to 22 years, with no current or past history of major depression, bipolar disorder or psychosis will be recruited across UK, Germany, Spain, and Belgium. Assessments take place at baseline (pre-randomisation), 1, 3 and 12 months post-randomisation. Primary endpoint and outcome for PREVENT is level of depression symptoms on the Patient Health Questionnaire-9 at 3 months; primary endpoint and outcome for PROMOTE is emotional well-being assessed on the Warwick-Edinburgh Mental Wellbeing Scale at 3 months. Depressive symptoms, anxiety, well-being, health-related quality of life, functioning and cost-effectiveness are secondary outcomes. Compliance, adverse events and potentially mediating variables will be carefully monitored. CONCLUSIONS: The trial aims to provide a better understanding of the causal role of learning EC skills using interventions delivered via mobile phone apps with respect to promoting well-being and preventing poor mental health in young people. This knowledge will be used to develop and disseminate innovative evidence-based, feasible, and effective Mobile-health public health strategies for preventing poor mental health and promoting well-being. TRIAL REGISTRATION: ClinicalTrials.gov ( www.clinicaltrials.org ). Number of identification: NCT04148508 November 2019.


Subject(s)
Cell Phone , Mobile Applications , Adolescent , Adult , Belgium , Germany , Humans , Mental Health , Prospective Studies , Quality of Life , Spain , Young Adult
3.
Int J Oral Maxillofac Surg ; 48(4): 560-565, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30392706

ABSTRACT

The aim of this study was to assess the clinical and microbiological parameters around dental zirconia and titanium implants compared with natural teeth during experimental plaque accumulation. Clinical parameters were evaluated (gingival index, plaque index, bleeding on probing, and probing pocket depth). Microbiological samples were analyzed for total bacterial cell counts, as well as Tannerella forsythia and Prevotella intermedia counts. A statistically significant difference over time was observed in the groups in terms of the gingival index (P<0.001), plaque index (P<0.001), and bleeding on probing (P=0.039). The lowest mean total number of bacterial cells was measured around the teeth, followed by the zirconia implants; the highest values were found around the titanium implants. T. forsythia and P. intermedia values showed significant changes over time and sessions around the titanium implants. Compared to the soft tissues around zirconia implants and the teeth, those around titanium implants developed a stronger inflammatory response to experimental plaque accumulation in terms of the total number of bacterial cells and T. forsythia and P. intermedia values.


Subject(s)
Dental Implants , Mucositis , Dental Plaque Index , Humans , Titanium , Zirconium
4.
Int J Oral Maxillofac Surg ; 47(4): 492-498, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29126690

ABSTRACT

The aim of this study was to measure bone levels around zirconia implants during follow-up of up to 3 years. Additionally, the effect of clinical contact point positions on the papilla deficit was evaluated. Eighty-one patients with 105 zirconia implants were examined at the 3-year follow-up. Bone levels were measured on the date of implant placement and at 3 months, 1year, and 3 years thereafter. Distances between the first bone-implant contact and the contact point of the crowns and between the bone level at the adjacent tooth and the contact point of the crowns were assessed. The effect of the clinical contact point position on the papilla deficit was also assessed. Significant reductions in the distances between the bone-implant contact and the implant shoulder, as well as the contact point of the crowns, and between the bone level at the adjacent tooth and the contact point of the crowns, were found. A significant association was found between the papilla deficit and the height of the contact point. Implant survival was 100% and implant success was 95.4%. While zirconia implants presented little bone loss up to 1year, significant bone apposition was observed up to 3years. Low contact points correlated with full papillae, whereas high contact points were associated with a papilla deficit.


Subject(s)
Alveolar Process/anatomy & histology , Dental Implants, Single-Tooth , Dental Papilla/anatomy & histology , Dental Prosthesis, Implant-Supported , Adult , Aged , Crowns , Dental Implantation, Endosseous/methods , Dental Prosthesis Design , Esthetics, Dental , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Zirconium
5.
Br J Oral Maxillofac Surg ; 54(8): 883-888, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27282083

ABSTRACT

The pathogenesis of bisphosphonate-related osteonecrosis of the jaw (BRONJ) remains unknown, and the development of a reliable experimental model would help to improve our understanding of it. We used 12 domestic pigs of which 6 made up the experimental group and were treated with zoledronate 4mg intravenously weekly for 5 weeks, while the control group (n=6) were given no drugs. On day 60 the right second maxillary and mandibular third molars were extracted. Thirty days later 3 animals in each group were killed; the rest were killed 90 days later. Histopathological specimens from the extraction sites were analysed for bone density, collagen architecture, density of osteons, and the amount of non-mineralised bone. Bone density, amount of non-mineralised bone, and density of osteons differed significantly between the 2 groups (p<0.001 in each case), but the chromatic pattern dictated by the collagen architecture did not. Our results correspond to the observations that have been made in patients with BRONJ, which means that the histomorphometric conditions seen in patients can be reproduced in this experimental setting.


Subject(s)
Bisphosphonate-Associated Osteonecrosis of the Jaw , Diphosphonates/adverse effects , Disease Models, Animal , Animals , Bone Density , Bone Density Conservation Agents , Haversian System , Humans , Molar , Osteonecrosis , Swine
6.
J Craniomaxillofac Surg ; 43(10): 1966-73, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26616405

ABSTRACT

OBJECTIVES: The animal study aims to evaluate a new experimental model for measuring sole the influence of the surface characteristics independent from implant macro-design on the level of osseointegration by registering the pull-out strength needed for removal of experimental devices with different surfaces from artificial defects. MATERIAL AND METHODS: Seventy-two test bodies (36 with the FRIADENT(®) plus surface, 36 with the P15/HAp biofunctionalized surface) were inserted in six adult domestic pigs with artificial calvarial defects. The experimental devices were designed to fit in the defects leaving a gap between the test body and the local bone. After 21 days of healing, the animals were sacrificed and the test bodies were pulled out with a standardised reproducible pull-out device measuring the pull-out strength. The pull-out strength for both groups was compared. RESULTS: Twenty-one days after insertion a mean force of 412 ± 142 N for the P15/HAp group and 183 ± 105 N for the FRIADENT(®) plus group was measured for the removal of the specimens from the calvarial bone. The difference between the groups was statistically significant (p < 0.0001). CONCLUSION: The experimental set-up seems to be a suitable method when measuring the impact of implant surfaces on the early stage of osseointegration.


Subject(s)
Dental Implants , Osseointegration/physiology , Wound Healing/physiology , Animals , Biomechanical Phenomena , Bone and Bones , Dental Prosthesis Retention , Dental Stress Analysis/instrumentation , Pilot Projects , Stress, Mechanical , Surface Properties , Swine , Titanium
7.
Eur J Dent Educ ; 17(2): 106-13, 2013 May.
Article in English | MEDLINE | ID: mdl-23574188

ABSTRACT

OBJECTIVE: In 2008, a consensus meeting of the Association for Dental Education in Europe stated that dental implant treatment represents a popular treatment alternative and, therefore, it should be an integral part of dental student pre-graduate education. In 2009, the Friedrich-Alexander University, Erlangen-Nuremberg implemented a voluntary, structured, education program for pre-graduate dental students, called 'i.lect'. The present study evaluated the effectiveness of the i.lect program. METHODS: Concurrent to the dental curriculum, the i.lect program provides 200 hours in 3 years of theoretical and practical education on all aspects of modern dental implantology. We recruited dental students in the i.lect program and additionally students from 15 other universities that voluntarily participated in a single, 3-day implantology camp (R = 58). To demonstrate their knowledge on dental implant issues, both student groups completed a written examination that covered 'Basic information and materials of implantology', 'Implant planning' and 'Soft tissue management'. RESULTS: The students in the i.lect program achieved higher scores than students from the implantology camp on questions concerning 'basic implantology' and 'implant planning'. CONCLUSION: The results indicated that the structured i.lect undergraduate curriculum enhanced individual knowledge in the specific field of implantology. This program could have pilot character for use in other universities.


Subject(s)
Dental Implantation/education , Education, Dental/methods , Models, Educational , Curriculum , Educational Measurement , Germany , Humans
8.
Clin Oral Implants Res ; 24(2): 128-34, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22111960

ABSTRACT

OBJECTIVES: Diabetes mellitus is currently classified as a relative contraindication for implant treatment because of microangiopathies with the consequence of impaired bone regeneration and higher rates of implant failure. The study aim was to investigate peri-implant bone formation in a diabetic animal model in comparison to healthy animals and to evaluate the differences between conventional (SLA(®) ) and modified (SLActive(®) ) titanium implant surfaces on osseointegration. MATERIAL AND METHODS: Each six implants were placed in the calvaria of 11 diabetic and 4 healthy domestic pigs. At 30 and 90 days after implant placement, the bone-to-implant contact (BIC) and bone density (BD) were appraised. Additionally, the expression of the bone-matrix proteins collagen type I and osteocalcin was evaluated at both points in time by using immunohistochemical staining methods. RESULTS: Overall, BIC was reduced in the diabetic group at 30 and 90 days. After 90 days, the SLActive(®) implants showed significantly higher BICs compared with the SLA(®) implants in diabetic animals. Peri-implant BD was higher in the SLActive(®) group at 30 and 90 days in healthy and diabetic animals. Collagen type I protein expression was higher using SLA(®) implants in diabetic pigs at 30 days. Values for osteocalcin expression were not consistent. CONCLUSIONS: The results indicate the negative effect of untreated diabetes mellitus on early osseointegration of dental implants. The modified SLA(®) surface (SLActive(®) ) elicited an accelerated osseointegration of dental implants, suggesting that a better prognosis for implant treatment of diabetic patients is possible.


Subject(s)
Dental Implantation, Endosseous , Dental Implants , Diabetes Mellitus, Experimental/complications , Osseointegration/drug effects , Skull/surgery , Titanium/pharmacology , Animals , Bone Density , Bone Regeneration , Collagen Type I/metabolism , Dental Restoration Failure , Osteocalcin/metabolism , Surface Properties , Swine
9.
Clin Oral Implants Res ; 24(7): 781-6, 2013 Jul.
Article in English | MEDLINE | ID: mdl-22458517

ABSTRACT

OBJECTIVE: This study aimed at identifying the ideal concentration of a biofunctional surface coating of dental implants with a synthetic peptide (P-15). In a previous study, P-15 was shown to enhance osseointegration parameters. MATERIAL AND METHODS: Implants (modified ANKYLOS(®) A8; FRIADENT Plus(®) surface) with five different concentrations (0-400 µg/ml) of a P-15 coating as well as uncoated controls were inserted in the frontal bone of 45 adult domestic pigs. The histomorphometric and microradiographic findings for the coated implants were compared to those for the uncoated ones after 7, 14, and 30 days. RESULTS: No significant differences were observed comparing the peri-implant bone density between the coated and uncoated implants The bone-to-implant contact, as the primary histological parameter for osseointegration, showed high rates for all surfaces investigated (between 73.3 ± 17.9% for the control and 81.9 ± 15.2% for P15 20 µg/ml after 30 days). CONCLUSIONS: No significant benefit on osseointegration of a biofunctional P-15 coating of dental implants could be displayed in the present study.


Subject(s)
Coated Materials, Biocompatible/chemistry , Collagen/chemistry , Dental Implants , Peptide Fragments/chemistry , Animals , Bone Density/physiology , Coated Materials, Biocompatible/administration & dosage , Collagen/administration & dosage , Durapatite/chemistry , Electrochemical Techniques , Female , Frontal Bone/pathology , Frontal Bone/surgery , Microradiography/methods , Osseointegration/physiology , Osteogenesis/physiology , Peptide Fragments/administration & dosage , Random Allocation , Surface Properties , Swine , Time Factors
10.
J Craniomaxillofac Surg ; 40(8): e301-6, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22417769

ABSTRACT

In the present paper we report the oral findings of a patient who was diagnosed with hyperoxaluria. Hyperoxalurias can basically be classified as primary and secondary, with the first being inborn errors of metabolism and the second a result of excessive oxalate intake. Primary hyperoxalurias form a rare group of metabolic diseases that are inherited in the autosomal recessive fashion. The affected genes code for specific hepatic enzymes that are involved in glyoxylate metabolism and their deficiency results in overproduction of oxalate. Two different types are described: Primary hyperoxaluria type I results from a deficiency of peroxisomal enzyme alanine-glyoxylate aminotransferase and the more rare type II from a deficiency of cytosolic enzyme D-glycerate dehydrogenase. Since oxalate is primarily excreted through the kidneys, abnormally high concentration of oxalate in the urine occurs. This can in turn result in recurrent kidney stones and parenchymal renal damage and end-stage renal disease (ESRD). Inability to further excrete oxalate through the kidneys leads to its deposition in various organs (oxalosis). Several oral findings have been described in patients with oxalosis, most important of whose are bone resorption in the jaws, external root resorption and rapidly progressive dental mobility, as well as dental pain associated with deposition of oxalate in the dentine and the pulp.


Subject(s)
Hyperoxaluria, Primary/complications , Periodontal Diseases/etiology , Tooth Diseases/etiology , Alveolar Bone Loss/etiology , Chronic Periodontitis/etiology , Gingivitis/etiology , Humans , Incisor/pathology , Molar/pathology , Osteolysis/etiology , Root Resorption/etiology , Tooth Apex/pathology , Tooth Loss/etiology , Tooth Mobility/etiology
11.
Clin Oral Implants Res ; 21(7): 726-34, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20636727

ABSTRACT

OBJECTIVES: The early stages of peri-implant bone formation play an essential role in the osseointegration and long-term success of dental implants. By incorporating bioactive coatings, this biofunctionalization of implant surfaces may enhance the attachment of the implant to the surrounding bone and stimulate bone regeneration. MATERIAL AND METHODS: To demonstrate faster osseointegration, the surfaces of dental implants were grit-blasted and acid-etched. They were then coated with hydroxyapatite (HA) and experimental implants were further coated with a biomimetic active peptide (P-15) in one of two concentrations. These biofunctionalized samples and controls with no peptide were placed in the forehead region of 12 adult pigs. Six animals were evaluated for a period of 14 or 30 days. RESULTS: Histomorphometric analysis demonstrated that the implants with the high concentration of P-15 had significantly higher percentage of bone-to-implant contact (BIC) at 14 (P=0.018) and 30 (P=0.015) days compared with the other groups. Both concentrations of P-15 showed increased peri-implant bone density compared to the control group at 30 days. CONCLUSION: Biofunctionalization of the implant surface with a biomimetic active peptide leads to significantly increased BIC rates at 14 and 30 days and higher peri-implant bone density at 30 days.


Subject(s)
Coated Materials, Biocompatible/pharmacology , Collagen/pharmacology , Dental Implants , Osseointegration/drug effects , Peptide Fragments/pharmacology , Animals , Bone Density/physiology , Bone Morphogenetic Proteins/biosynthesis , Cell Adhesion/drug effects , Coated Materials, Biocompatible/administration & dosage , Dental Implantation, Endosseous , Dose-Response Relationship, Drug , Frontal Bone/surgery , Microradiography , Surface Properties , Sus scrofa , Titanium
12.
J Neuroimmunol ; 216(1-2): 85-91, 2009 Nov 30.
Article in English | MEDLINE | ID: mdl-19781791

ABSTRACT

Little is known about pathogenesis -- and especially about involvement of CD8(+) T-cells -- in late-onset myasthenia gravis (LOMG). Remarkably, outstanding CD8(+) TCRVbeta-subset expansions were found in 64% and 72% of recent onset LOMG or thymoma-associated MG (vs. 16% with early-onset MG (p<0.0002); 21% in older controls (p<0.001)). In LOMG, ~25% of the expanded cells initially showed a naïve CD62L(+hi)/CD45RA(+) recent thymic emigrant (RTE)-like phenotype. These expansions associated significantly with IgG antibodies against cytomegalovirus (p<0.036), IL-12 and/ or IFN-alpha2 (p<0.03). The CD8(+) TCRVbeta expansions were stable over 5years, but RTE markers declined.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Myasthenia Gravis/immunology , Receptors, Antigen, T-Cell, alpha-beta/physiology , Thymoma/immunology , Adult , Age of Onset , Aged , Autoantibodies/blood , CD8-Positive T-Lymphocytes/metabolism , Cytomegalovirus/immunology , Diagnosis, Differential , Female , Humans , Immunophenotyping , Interferon-gamma/immunology , Interleukin-12/immunology , L-Selectin/metabolism , Leukocyte Common Antigens/metabolism , Lymphocyte Activation/immunology , Male , Middle Aged , Myasthenia Gravis/metabolism , Myasthenia Gravis/physiopathology , Recombinant Proteins , Thymoma/metabolism , Thymoma/physiopathology
13.
Vox Sang ; 94(1): 64-9, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18005082

ABSTRACT

BACKGROUND AND OBJECTIVES: The atrophic posterior maxilla often requires restoration of the alveolar ridge due to a lack of bone quantity and quality before dental implant placement. The aim of this study was to verify the hypothesis that platelet-rich plasma (PRP) has an influence on bone density in the maxilla after sinus floor elevation in combination with autologous cancellous bone from the iliac crest. Therefore, a randomized, prospective, controlled trial was set up in two centres. STUDY DESIGN AND METHODS: Fifty-three patients who underwent osteoplastic bone grafting for sinus floor elevation were included. The intervention group was treated with defined concentrations of PRP in addition to transplanted bone. Bone biopsy was performed 4 months after augmentation. Bone volume was then measured using the histomorphometric parameter bone volume. RESULTS: The histomorphometric evaluation of the biopsies did not indicate superiority of any of the treatments in terms of bone volume. CONCLUSION: Topical use of PRP did not improve maxillary bone volume either clinically relevant or statistically significant compared to that in conventionally treated patients. The use of PRP to support bone regeneration cannot be recommended as a standard method for maxillary augmentation.


Subject(s)
Dental Implantation, Endosseous/methods , Maxilla/surgery , Platelet-Rich Plasma , Administration, Topical , Bone Regeneration , Bone Transplantation , Dental Implants , Humans , Imaging, Three-Dimensional , Maxilla/pathology , Prospective Studies , Transplantation, Autologous
14.
Ophthalmologe ; 105(6): 578-83, 2008 Jun.
Article in German | MEDLINE | ID: mdl-17899120

ABSTRACT

In the case of displacement of the globe such as enophthalmos induced by trauma, the patient is affected on both counts: function and aesthetics. To prevent double vision or conspicuous asymmetry, exact correction of the globe position is required. The aim of this case report is to demonstrate an intraoperative computer-assisted, non-contact, optical 3D procedure for identification of the globe position to aid in placing the eyeball in the position required in complex reconstruction of the orbital floor. A 33-year-old man presented with a sunken eye on the right side in the horizontal and vertical plane 6 months after having undergone surgery elsewhere for a zygomatico-orbital fracture, also including the orbital floor. The patient was affected by double vision and a noticeable defective globe position. In planning the correction of the globe position, a three-dimensional image of the face with opened eyes was made with the optical sensor. Automatic comparison of symmetry revealed enophthalmos of 4 mm on relative en- and exophthalmometry. The decision was made to lift the orbital floor with a split calvarial bone graft. During surgery the position of the globe was also controlled by the three-dimensional optical technique. At the end of surgery there was exophthalmos of 1 mm. Six weeks after surgery the patient was not affected by any double vision. After 3 and 24 months enophthalmos was 1 mm. This case demonstrates how the non-ionizing, non-contact, optical 3D technique can help in planning, intraoperative transformation, and clinical monitoring to identify the correct position of the corneal vertex in complex orbital floor reconstruction.


Subject(s)
Diagnostic Imaging/methods , Diagnostic Techniques, Ophthalmological , Enophthalmos/surgery , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Orbit/surgery , Surgery, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , User-Computer Interface , Adult , Diplopia/etiology , Diplopia/surgery , Enophthalmos/diagnosis , Facial Injuries/complications , Facial Injuries/surgery , Fracture Fixation, Internal , Humans , Male , Orbit/injuries , Postoperative Complications/diagnosis , Postoperative Complications/surgery , Skiing/injuries , Zygomatic Fractures/complications , Zygomatic Fractures/surgery
15.
HNO ; 56(11): 1142-7, 2008 Nov.
Article in German | MEDLINE | ID: mdl-17891362

ABSTRACT

Pronounced enophthalmos can restrict patients both functionally and aesthetically. Typical symptoms are double vision on both eyes and obvious asymmetry, both of which were present in the 67-year-old male patient presented in this paper. The resulting data of computed tomography was used to fabricate a patient specific ceramic implant for reconstruction of the left orbital floor with an enophthalmos of 4mm. During the surgery the implant fitted anatomically correct, but exophthalmos occurred. The implant needed to be regraded and recontoured in the dorsal fraction, so that overcorrection could be reduced. With the assistance of optical 3D en- and exophthalmometry during surgery, the position of the cornea vertex was reproducible measured. At the end of surgery, exophthalmos was 1.5 mm. After 12 months, enophthalmos of only 1mm exists. This case displays the combination of a patient specific fabricated implant for reconstruction of the orbital floor with optical 3D-en-and exophthalmometry to correct enophthalmos with a high degree of accuracy. Therefore these two techniques in combination should be used when complex corrections of enophthalmos are needed.


Subject(s)
Computer-Aided Design , Enophthalmos/diagnostic imaging , Enophthalmos/surgery , Imaging, Three-Dimensional/methods , Plastic Surgery Procedures/instrumentation , Plastic Surgery Procedures/methods , Prostheses and Implants , Surgery, Computer-Assisted/methods , Aged , Humans , Male , Radiography , Treatment Outcome
16.
J Prosthet Dent ; 98(4): 251-5, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17936123

ABSTRACT

The long-term clinical and esthetic success of an implant-supported restoration is determined by stable periimplant soft-tissue morphology that is in harmony with the surrounding tissue architecture of the natural dentition. An interdisciplinary approach can significantly improve predictability when restoring missing teeth in the anterior maxilla. This clinical report describes the application of forced orthodontic eruption prior to initiation of surgical and restorative implant treatment to achieve a coronal shift of bone and gingiva and enhance the 3-dimensional topography of the recipient implant site.


Subject(s)
Dental Implantation, Endosseous/methods , Dental Implants, Single-Tooth , Dental Prosthesis, Implant-Supported , Incisor , Orthodontic Extrusion , Adult , Female , Humans , Maxilla , Patient Care Team , Tooth Extraction , Tooth Socket
17.
Biomaterials ; 28(17): 2772-82, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17339051

ABSTRACT

Successful bone-implant osseointegration in large peri-implant bone defects is often difficult, even through autologous bone grafting. Recently, cell-mediated regional gene therapy was introduced to deliver potent morphogens or growth factors in regenerative medicine. We applied liposomal vectors carrying bone morphogenetic protein (BMP)-2 cDNA directly into freshly created peri-implant bone defects on pig calvariae, with or without autologous bone graft. The BMP-2 gene was efficiently introduced into immigrating cells and trabecular cells lining the marginal bone surrounding the bony defect. After 1 week, abundant BMP-2 protein was detected throughout the peri-implant bone defect by immunohistochemistry. At 4 weeks, BMP-producing cells were still present in the defect and peri-implant area, which significantly enhanced new bone formation, compared with the control groups. Interestingly within a week of BMP-2 gene delivery with bone grafts, most osteoblastic cells lining the grafted bone chips also produced BMP-2. Particulated bone was immediately reorganized into newly formed trabecular bone. Grafted bone without BMP-2 gene delivery was still scattered and new bone matrix formation was not detected until 4 weeks after bone grafting. In conclusion, direct application of the BMP-2 gene using a liposomal vector enhanced bone regeneration in a bony defect and gene delivery combined with bone graft could induce a rapid osseointegration of the bone-implant interface at earlier stage.


Subject(s)
Bone Morphogenetic Proteins/administration & dosage , Bone Morphogenetic Proteins/genetics , Bone Regeneration/physiology , Bone Transplantation/methods , Bone and Bones/abnormalities , Genetic Vectors/administration & dosage , Prostheses and Implants , Transforming Growth Factor beta/administration & dosage , Transforming Growth Factor beta/genetics , Animals , Bone Matrix/cytology , Bone Morphogenetic Protein 2 , Calcification, Physiologic/physiology , Gene Transfer Techniques , Humans , Liposomes , Regenerative Medicine , Stromal Cells/cytology , Swine
18.
J Plast Reconstr Aesthet Surg ; 60(6): 615-21, 2007.
Article in English | MEDLINE | ID: mdl-17392045

ABSTRACT

We report on our experience using a new endosseous implant designed to provide sufficient retention to various types of facial prostheses. In a preclinical animal experiment implants (N=12, 4 x 3.5 mm) were placed in the frontal calvarial region of nine adult pigs. The animals were sacrificed at 2, 4 and 8 weeks to evaluate the implant incorporation microradiographically. The clinical outcome and patient satisfaction of implant-retained prostheses were evaluated in a group of 10 patients with facial defects by using clinical assessment and standardized questionnaires for patients and relatives. In the prospective clinical study 33 identical modified implants for extraoral anchorage were placed for the fixation of various prostheses in the midfacial (eye, nose) and ear regions in the course of a clinical trial and observed over a follow-up period of 34 months. The bone-implant contact in the animal experiment reached 31% (+/-2) at 2 weeks, 39% (+/-1) after 4 weeks and 51% (+/-5) at 8 weeks. In the clinical trial, no implants were lost and all implants remained osseointegrated as confirmed clinically and radiographically, providing a stable prosthetic restoration. The analysis of the questionnaire indicates an improvement of the quality of life of patients with respect to aesthetic and psychological well-being. The results demonstrate that extraoral implants not only achieve sufficient osseointegration but also show good clinical handling and easy fixation possibilities for prosthetic anchorage.


Subject(s)
Face/surgery , Maxillofacial Prosthesis Implantation/methods , Skull/surgery , Adult , Animals , Child , Ear, External/surgery , Follow-Up Studies , Humans , Male , Nose/surgery , Orbit/surgery , Osseointegration/physiology , Patient Satisfaction , Postoperative Complications , Prospective Studies , Skin/physiopathology , Swine , Treatment Outcome
19.
Br J Oral Maxillofac Surg ; 45(1): 41-7, 2007 Jan.
Article in English | MEDLINE | ID: mdl-16713040

ABSTRACT

We created defects of standard size in the frontal bones of adult pigs and filled them with four different materials. On six occasions (at 1, 2, 4, 8, 12, and 26 weeks), samples were harvested, and evaluated by computing microradiographic images. We examined the specimens histologically as controls. After insertion of anorganic materials, microradiographic evaluation was easy and precise, and there were no significant differences between them and the histological controls (p=0.2). A quantitative evaluation of chemically sterilised bone by computer was not possible for more than 4 weeks.


Subject(s)
Bone Substitutes/therapeutic use , Frontal Bone/surgery , Animals , Bone Density/physiology , Bone Diseases/pathology , Bone Diseases/surgery , Bone Matrix/transplantation , Bone Transplantation , Durapatite/therapeutic use , Female , Frontal Bone/pathology , Image Processing, Computer-Assisted , Microradiography , Minerals/therapeutic use , Osseointegration/physiology , Osteogenesis/physiology , Swine , Transplantation, Autologous
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