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Background and Objective: Ultraviolet (UV)-irradiated 7-dehydrocholesterol (7-DHC) and vitamin E (VitE)-coated titanium (Ti) implants have a beneficial effect on bone cells. Human gingival fibroblasts (HGFs) are the most abundant cells in periodontal tissues and are involved in the wound healing and repair. The objective of this study was to evaluate the response of HGFs to Ti implants coated with UV-irradiated 7-DHC and VitE, for improved soft-tissue integration of dental implants., Material and Methods: Ti surfaces were coated with 7-DHC and VitE, irradiated with UV light and incubated for 48 h at 23°C to allow cholecalciferol (D3 ) synthesis from 7-DHC onto the Ti surface. HGFs were cultured on the modified surfaces and the influence of the coating on these cells was evaluated through the analysis of: (i) biocompatibility; (ii) the mRNA levels of genes involved in the composition and turnover of the extracellular matrix, the inflammatory response, periodontal bone resorption and wound healing; and (iii) the levels of MMP-1 and TIMP-1 proteins., Results: We found a beneficial effect of UV-irradiated 7-DHC:VitE-coated Ti implants on HGFs. Besides being biocompatible with HGFs, the UV-irradiated 7-DHC and VitE coating increased the levels of collagen III α1 and fibronectin mRNAs. and decreased the level of interleukin-8 mRNA. TIMP-1 was increased at both mRNA and protein levels in HGFs cultured on UV-irradiated 7-DHC:VitE-coated Ti implants. Finally, the UV-irradiated 7-DHC and VitE coating decreased the level of RANKL mRNA in HGFs., Conclusion: UV-irradiated 7-DHC:VitE-coated Ti implants have a positive effect on HGFs in vitro by reducing the inflammatory response and extracellular matrix breakdown., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aim: Temporal and spatial expression pattern of extracellular matrix (ECM) components in furcation defects following guided tissue regeneration (GTR) compared with open-flap debridement (OFD)., Material and Methods: In 21 dogs, mandibular second and fourth pre-molars were treated with one non-resorbable and three different resorbable membranes. Third pre-molars were treated by OFD. After 2, 4, 8 weeks and 3, 6, and 12 months, tissues were analysed by immunohistochemistry for collagen I (Col-I) and III (Col-III), fibronectin (FN), bone sialoprotein (BSP), and osteopontin (OPN)., Results: At 2 weeks, the defect was mainly occupied by FN+ granulation tissue (GT), which was sequentially replaced by new connective tissue expressing FN, Col-I, and increasingly Col-III. Following superficial resorptions by OPN+ osteoclasts and odontoclasts, cementum and bone formation ensued with strong expression of BSP and OPN along bone and tooth surfaces. Deposition of Col-I, FN, BSP and OPN+ cementoid and osteoid became evident after 4 weeks. Extrinsic fibres of cementum and bone stained intensely for Col-III. The newly formed periodontal ligament expressed FN, Col-I, and Col-III, but no BSP or OPN., Conclusions: The spatial ECM expression was similar for OFD and the different GTR methods, although the timing and quantity of ECM expression were influenced by wound stabilization and inflammatory reactions.

Over the past 10 years, there have been 137 patient safety incidents in England associated with methotrexate prescribing. Recent reports show that Australia has similar concerns. Using the valuable tool of an audit, we reviewed our departmental prescribing practices for 49 patients with psoriasis on methotrexate. Results highlighted poor documentation that patients were receiving appropriate information sheets detailing complications of the drug. Inconsistencies between prescribers were also noted, particularly in regards to haematological monitoring. A review of the current published work and the guidelines of other leading centres was performed and consistent, evidence-based guidelines were produced for the department. Such guidelines are essential in order to minimize the recognized complications of methotrexate. Recent studies highlight procollagen peptide III as a valuable adjunct for monitoring hepatotoxicity, while there is no longer a significant role for routine recording of cumulative dose. It would be valuable to repeat the audit to ensure a change in practice and an improved adherence to common guidelines.

Immunoexpression of the extracellular matrix (ECM) proteins laminin, fibronectin, tenascin and types I, III and IV collagen was analyzed in the major and minor salivary glands of seven human fetuses at different gestational ages. The results showed the presence and localization of laminin, collagen IV and fibronectin around glandular structures at all stages of development. Tenascin was only detectable around excretory ducts. In the earliest stages of development, type I and type III collagen were presented as fine fibers delineating the glandular structures and delimiting the extension of the future lobule. As glandular development proceeded, the lobule was gradually filled with collagens and glandular tissue., (Copyright Eur J Oral Sci, 2004.)

Primary and secondary cartilages differ in embryonic origin and in histological organization, and are generally considered to have a different mode of growth. However, few studies have directly compared the two types of cartilage of the same animal at the same age. Therefore, we analysed several histological and biochemical differences between secondary cartilage of the mandibular condyle and primary cartilage of the femoral head of 4-d-old rats. We evaluated the tissue organization, the level of DNA and glycosaminoglycan (GAG) synthesis, and the GAG and collagen content. The expression of collagen types I, II and III and of receptors for insulin-like growth factor (IGF)-I, fibroblast growth factor (FGF), and transforming growth factor (TGF)-beta were investigated by immunohistochemistry. The ex vivo DNA and GAG synthesis as well as the GAG content of femoral heads were much higher than that of mandibular condyles. Mandibular condyles expressed both collagen types I and II, while femoral heads expressed only type II collagen. In the mandibular condyles, receptors for IGF-I, FGF, and TGF-beta were observed mainly in the superficial layers, whereas they were found throughout the entire femoral head. In conclusion, major differences were found between both types of cartilage, which might be related to their specific functional demands.

This study was designed to study wound strength at the dentine/connective tissue interface and at the bone/connective tissue interface following full thickness flap surgery. Flaps of uniform dimension were outlined in four young adult beagle dogs using a standardised double bladed knife and vertical incisions 10 mm apart, which extended 8 mm apical to the gingival margin. Bone was removed from half the sites (eight sites in each dog), giving 32 flaps replaced on dentine and 32 sites on bone. A tensile force was applied using a microprocessor force gauge at 1, 2, 3, 7, 10, 14, 21, and 28 days. Mean tensile strengths were markedly weaker for the dentine/flap interface. At 7 days the value for flaps to dentine was 1.82 N, in contrast to 5.08 N for flaps replaced on bone. Inflammatory cell counts tended to fall markedly at 3 days for both modalities, but were higher for the dentine/flap modality at all time points. Fibroblast density peaked at 7-14 days but did not vary with type of flap over the time points studied. The amounts of fibrin were greater for the dentine/flap interface at all time points but decreased for both flap types as time progressed. Collagen type V was localised to the basement membrane and blood vessels and tended to show more foci for flaps replaced on dentine. Procollagen levels showed little change over the healing interval for both flap/bone and flap/dentine interfaces. Type III collagen synthesis was at peak levels during the first week. These findings would support efforts to stabilise periodontal flaps at early time points, especially those on dentine.

Background: Wound contraction and scar formation in the palatal mucoperiosteum after cleft palate surgery impair maxillary growth. The aim of this study was to determine the effects of IFN-beta on palatal mucoperiosteal wound healing in growing rats., Methods: Standardized wounds were made in the palatal mucoperiosteum of young rats. Either IFN-beta or vehicle were injected at the wound site between 4 and 29 days after wounding. The results were compared with control wounds. Tissue samples were collected at 8, 15, 30, and 60 days PW for biochemical and microscopic analysis., Results: IFN-beta stimulated re-epithelialization but did not reduce the number of myofibroblasts or scar tissue formation. Surprisingly, the injection of vehicle alone delayed the healing process., Conclusion: IFN-beta might be suitable to stimulate re-epithelialization but it does not reduce scar tissue formation in rat palatal wound healing. The injection of agents into palatal wounds might severely impair the healing process.