Dermale Regeneration mit einer porkinen Kollagen-I/III-Membran: Experimentelle Untersuchung von Epithelisierung, Vaskularisation und Matrixintegration

Fragestellung und Ziele: Das Ziel des vorliegenden Dissertationsprojektes bestand in der experimentellen Evaluation einer biodegradierbaren, porkinen Kollagen-I/III-Matrix bezüglich der Eigenschaften Epithelisierung, Vaskularisation und Matrix-remodeling als für den klinischen Erfolg maßgeblichen Parametern im Vergleich zur Standardtherapie des autologen Spalthauttransplantates. Methodik: An 21 adulten Hausschweinen wurden auf der Ohrrückseite jeweils 3 standardisierte dermale Vollhautdefekte mit Spalthaut-Transplantat, einer mit der porkinen Kollagen I/III-Membran und durch freie Granulation zur Ausheilung gebracht. An den postoperativen Tagen 1, 3, 5, 7, 14 und 28 wurden Proben der Defektmodaltäten histologisch (HE, Sirius-Rot), immunhistochemisch (TGFβR-III, Zytokeratin 5/6) und immunchemisch (TGFβ1, TGFβ3, Smad 2/3) analysiert. Ergebnisse und Diskussion: Epithelisierung und Neovaskularisation unterschieden sich nicht signifikant zwischen Spalthaut-gedecktem und Membran-gedecktem Defekt. Die dermale Regeneration von Vollhautdefekten kann durch Einsatz der Membran im Vergleich zur freien Granulation beschleunigt und durch Vermeidung eines Spalthauttransplantates die Morbidität der Spenderregion vermindert werden

Implication of bisphosphonate use in the treatment of SAPHO syndrome: Case report and discussion of current literature

AbstractEven though increasing knowledge is emerging about synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome its pathogenesis remains enigmatic. Women are preferentially affected by SAPHO syndrome. Here we present the case of a 39-year-old woman suffering from this syndrome whose bone involvement was first interpreted as diffuse sclerosing osteomyelitis of the mandible. As treatment with clindamycin did not improve the symptoms, the decision was made to administer bisphosphonates intravenously. This treatment led to a rapid improvement in symptoms, which could be explained by the apparent tendency of bisphosphonates to exert a positive effect on the jaw. With this case report we attempt to offer an explanation for the influence of this group of medications on patients suffering from SAPHO syndrome with mandibular involvement

Bisphosphonate-associated osteonecrosis of the jaw is linked to suppressed TGFβ1-signaling and increased Galectin-3 expression: A histological study on biopsies

Background Bisphosphonate associated osteonecrosis of the jaw (BRONJ) implies an impairment in oral hard- and soft tissue repair. An understanding of the signal transduction alterations involved can inform therapeutic strategies. Transforming growth factor β1 (TGFβ1) is a critical regulator of tissue repair; galectin-3 mediates tissue differentiation and specifically modulates periodontopathic bacterial infection. The aim of this study was to compare the expression of TGFβ1-related signaling molecules and Galectin-3 in BRONJ-affected and healthy mucosal tissues. To discriminate between BRONJ-specific impairments in TGFβ1 signaling and secondary inflammatory changes, the results were compared to the expression of TGFβ1 and Galectin-3 in mucosal tissues with osteoradionecrosis. Methods Oral mucosal tissue samples with histologically-confirmed BRONJ (n = 20), osteoradionecrosis (n = 20), and no lesions (normal, n = 20) were processed for immunohistochemistry. Automated staining with an alkaline phosphatase-anti-alkaline phosphatase kit was used to detect TGFβ1, Smad-2/3, Smad-7, and Galectin-3. We semiquantitatively assessed the ratio of stained cells/total number of cells (labeling index, Bonferroni-adjustment). Results TGFβ1 and Smad-2/3 were significantly decreased (p < 0.032 and p(0.028, respectively) in the BRONJ samples and significantly increased (p < 0.04 and p <0.043, respectively) in the osteoradionecrosis samples compared to normal tissue. Smad-7 was significantly increased (p < 0.031) in the BRONJ group and significantly decreased (p < 0.026) in the osteoradionecrosis group. Galectin-3 staining was significantly (p < 0.025) increased in both the BRONJ and the osteoradionecrosis (p < 0.038) groups compared to the normal tissue group. However, Galectin-3 expression was significantly higher in the BRONJ samples than in the osteoradionecrosis samples (p < 0.044). Conclusion Our results showed that disrupted TGFβ1 signaling was associated with delayed periodontal repair in BRONJ samples. The findings also indicated that impairments in TGFβ1-signaling were different in BRONJ compared to osteoradionecrosis. BRONJ appeared to be associated with increased terminal osseous differentiation and decreased soft tissue proliferation. The increase in Galectin-3 reflected the increase in osseous differentiation of mucoperiosteal progenitors, and this might explain the inflammatory anergy observed in BRONJ-affected soft tissues. The results substantiated the clinical success of treating BRONJ with sequestrectomy, followed by strict mucosa closure. BRONJ can be further elucidated by investigating the specific intraoral osteoimmunologic status

Osteonecrosis of the jaw in a Crohn’s disease patient following a course of Bisphosphonate and Adalimumab therapy: a case report

Background Bisphosphonates have a widespread indication for osteoporosis and are also applied in cancer patients with skeletal-related conditions. Bisphosphonate-associated osteonecrosis of the jaw (BRONJ) is a feared side effect which is hard to treat and often affects patient´s quality of life in an extensive manner. Adalimumab (Humira®), a fully human recombinant antibody specific for tumor necrosis factor- α, is approved for treatment in patients with Inflammatory Bowel Disease like ulcerative colitis or Crohn’s disease. Case presentation In March 2013, a 36-year-old female presented with right-sided perimandibular swelling, recurrent facial pain and exposed necrotic bone after previous extraction of tooth 47. She had the medical history of Crohn’s disease for more than one decade with chronic active enterocolitis, fistula disease as well as previous oral manifestation and was currently treated with Adalimumab since September 2008. Due to steroid-induced osteoporosis, diagnosed in 2004, she received oral Bisphosphonates (Risedronate) from 2004 until 2007 followed by two infusions of Zoledronic acid in 2008 and 2009. Conclusion This patient with a medical history of Crohn’s disease and gastrointestinal remission under Adalimumab therapy presented with osteonecrosis of the jaw after suspended oral and intravenous Bisphosphonate therapy implicating that the biologic therapy with an anti-TNF-α antibody might promote the manifestation of osteonecrosis and compromise oral healing capacity

Craniofacial Osteosarcoma—Pilot Study on the Expression of Osteobiologic Characteristics and Hypothesis on Metastasis

Background: Craniofacial osteosarcomas (COS) and extracranial osteosarcomas (EOS) show distinct clinical differences. COS show a remarkably lower incidence of metastases and a better survival. However, in contrast to EOS, they show a poor response to neoadjuvant chemotherapy. Tumor-associated macrophages and their polarization as well as developmental biological signaling pathways are possible candidates for explaining the clinical differences between COS and EOS. The aim of the study was to analyze differential expression of macrophage markers and important regulators of these pathways. Methods: Twenty osteosarcoma cases (10 COS and 10 EOS) were immunohistochemically stained to assess CD68, CD11c, CD163, MRC1, Gli1, and Gli2 expression. Statistical differences between COS and EOS were tested using the Mann–Whitney U test. Additionally, the paper describes an example of multidisciplinary treatment of a patient suffering from COS and discusses the surgical challenges in treatment and rehabilitation of COS. Results: COS showed a significantly (p < 0.05) increased infiltration of CD11c-positive M1 macrophages and a shift toward M1 polarization compared to EOS. Additionally, COS revealed a significantly (p < 0.05) lower Gli1 expression than EOS. Conclusion: The reduced Gli1 expression in COS can be interpreted as reduced activation of the Hedgehog (Hh) signaling pathway. The increased M1 polarization and reduced Hh activation in COS could explain the low incidence of metastases in these osteosarcomas

The Special Developmental Biology of Craniofacial Tissues Enables the Understanding of Oral and Maxillofacial Physiology and Diseases

Maxillofacial hard tissues have several differences compared to bones of other localizations of the human body. These could be due to the different embryological development of the jaw bones compared to the extracranial skeleton. In particular, the immigration of neuroectodermally differentiated cells of the cranial neural crest (CNC) plays an important role. These cells differ from the mesenchymal structures of the extracranial skeleton. In the ontogenesis of the jaw bones, the development via the intermediate stage of the pharyngeal arches is another special developmental feature. The aim of this review was to illustrate how the development of maxillofacial hard tissues occurs via the cranial neural crest and pharyngeal arches, and what significance this could have for relevant pathologies in maxillofacial surgery, dentistry and orthodontic therapy. The pathogenesis of various growth anomalies and certain syndromes will also be discussed

Alterations in macrophage polarization in the craniofacial and extracranial skeleton after zoledronate application and surgical interventions – an in vivo experiment

PurposeMedication-related osteonecrosis occurs exclusively in the jaw bones. However, the exact pathogenesis of medication-related osteonecrosis of the jaw (MRONJ) and the unique predisposition of the jaw bones have not been elucidated, making its treatment a challenge. Recent evidence indicates that macrophages might play a pivotal role in MRONJ pathogenesis. The aim of the present study was to compare the macrophage populations between the craniofacial and extracranial skeleton and to investigate the changes induced by zoledronate (Zol) application and surgical interventions.Materials and methodsAn in vivo experiment was performed. 120 wistar rats were randomized to 4 groups (G1, G2, G3, G4). G1 served as an untreated control group. G2 and G4 received Zol injections for 8 weeks. Afterwards, the right lower molar of the animals from G3 and G4 was extracted and the right tibia osteotomized followed by osteosynthesis. Tissue samples were taken from the extraction socket and the tibia fracture at fixed time points. Immunohistochemistry was conducted to determine the labeling indexes of CD68+ and CD163+ macrophages.ResultsComparing the mandible and the tibia, we observed a significantly higher number of macrophages and a heightened pro-inflammatory environment in the mandible compared to the tibia. Tooth extraction caused an increase of the overall number of macrophages and a shift toward a more pro-inflammatory microenvironment in the mandible. Zol application amplified this effect.ConclusionOur results indicate fundamental immunological differences between the jaw bone and the tibia, which might be a reason for the unique predisposition for MRONJ in the jaw bones. The more pro-inflammatory environment after Zol application and tooth extraction might contribute to the pathogenesis of MRONJ. Targeting macrophages might represent an attractive strategy to prevent MRONJ and improve therapy. In addition, our results support the hypothesis of an anti-tumoral and anti-metastatic effect induced by BPs. However, further studies are needed to delineate the mechanisms and specify the contributions of the various macrophage phenotypes

Alterations in macrophage polarization in the craniofacial and extracranial skeleton after zoledronate application and surgical interventions – an in vivo experiment

Purpose Medication-related osteonecrosis occurs exclusively in the jaw bones. However, the exact pathogenesis of medication-related osteonecrosis of the jaw (MRONJ) and the unique predisposition of the jaw bones have not been elucidated, making its treatment a challenge. Recent evidence indicates that macrophages might play a pivotal role in MRONJ pathogenesis. The aim of the present study was to compare the macrophage populations between the craniofacial and extracranial skeleton and to investigate the changes induced by zoledronate (Zol) application and surgical interventions. Materials and methods An in vivo experiment was performed. 120 wistar rats were randomized to 4 groups (G1, G2, G3, G4). G1 served as an untreated control group. G2 and G4 received Zol injections for 8 weeks. Afterwards, the right lower molar of the animals from G3 and G4 was extracted and the right tibia osteotomized followed by osteosynthesis. Tissue samples were taken from the extraction socket and the tibia fracture at fixed time points. Immunohistochemistry was conducted to determine the labeling indexes of CD68+ and CD163+ macrophages. Results Comparing the mandible and the tibia, we observed a significantly higher number of macrophages and a heightened pro-inflammatory environment in the mandible compared to the tibia. Tooth extraction caused an increase of the overall number of macrophages and a shift toward a more pro-inflammatory microenvironment in the mandible. Zol application amplified this effect. Conclusion Our results indicate fundamental immunological differences between the jaw bone and the tibia, which might be a reason for the unique predisposition for MRONJ in the jaw bones. The more pro-inflammatory environment after Zol application and tooth extraction might contribute to the pathogenesis of MRONJ. Targeting macrophages might represent an attractive strategy to prevent MRONJ and improve therapy. In addition, our results support the hypothesis of an anti-tumoral and anti-metastatic effect induced by BPs. However, further studies are needed to delineate the mechanisms and specify the contributions of the various macrophage phenotypes

Zoledronate Causes a Systemic Shift of Macrophage Polarization towards M1 In Vivo

Background: Immunomodulatory properties of bisphosphonates (BP) are suggested to contribute to the development of medication-associated osteonecrosis of the jaw (MRONJ). Furthermore, bisphosphonate-derived immune modulation might contribute to the anti-metastatic effect observed in breast cancer patients. Macrophages are potential candidates for the mediation of immunomodulatory effects of bisphosphonates. The study aimed to investigate the influence of bisphosphonates alone and in combination with surgical trauma on systemic macrophage polarization (M1 vs. M2) using an in vivo rat model. Methods: A total of 120 animals were divided into four groups. Groups 2 and 4 were treated with 8 × 40 μg/kg body weight of the BP Zoledronate i.p. (week 0–7). Groups 3 and 4 were exposed to surgical trauma (week 8, tooth extraction + tibia fracture), whereas in Group 1 neither medication nor surgical trauma was applied. After 8, 10, 12 and 16 weeks, skin, lung and spleen were immunohistochemically examined for macrophage polarization via expression analysis of CD68, CD163 and iNOS using a tissue microarray (TMA). Results: A significant shift of macrophage polarization towards M1 was observed in skin, spleen and lung tissue of animals, with and without surgical trauma, treated with BP when compared to those without BP application. Surgical trauma did not cause a significant increase towards M1 polarization. Conclusions: BP application leads to a systemic pro-inflammatory situation in vivo, independent of surgical trauma, as evidenced by the shift in macrophage polarization towards M1 in various somatic tissues. This provides a possible explanation for the clinically observed anti-tumor effect of bisphosphonates and might also contribute to pathogenesis of MRONJ