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Background/Aim: Osteotomy as the first step in surgery, provides access to the field and its application could influence the outcome. Nowadays, the conventional burr reduction is being challenged by newer sonic and ultrasonic methods. We investigated the bone structural integrity and metal attrition residues both in bone and the irrigation fluid. Materials and Methods: Bovine ribs were cut using three methods. Bone cuts were studied using Environmental Scanning Electron Microscopy (ESEM) for tissue discrepancies and Scanning Electron Microscopy/Energy Dispersion X-Ray Microanalysis (SEM/EDX) for organic and inorganic debris. Results: Better preservation of bone architecture was seen in piezo and sono surgery while metal attrition was not conclusive (p>0.05). Unlike in bone analyses, both bur and ultrasonic osteotomies showed statistically significant higher median inorganic detection per analysis (p=0.021 and p=0.037, respectively). Conclusion: Sono and piezo surgery proved to be less invasive while attrition properties were the same.

For application of stem cells and progenitor cells in regenerative medicine, scaffolds for carrying the cells play a key role. One promising biomaterial for scaffold generation is silk because of its mechanical strength, good cytocompatibility and low immunogenicity. Furthermore, bioengineering of silk proteins enable co-expression of various growth, differentiation and angiogenic factors on silk fibers, which may promote cell growth, differentiation and angiogenesis. This study aimed to test cytocompatibility and growth/differentiation of pre-adipose cells on scaffolds with and without expressed growth factors fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF).Disk-form scaffolds of 15×3 mm (diameter × thickness) were manufactured in two different densities using silk with and without expressed growth factors FGF-2 or VEGF. Pre-adipose cells were prepared from fatty tissues of patients undergoing operation. Cells (1.6×10(6)) were seeded onto each of the silk-scaffold disks, that were placed into wells of 12-well culturing plates. Adipose-differentiation was induced using differentiation medium containing DMEM/F-12, insulin, pantothenate, biotin, triiodothyronine (T3), transferrin, dexamethasone, isobuthylmethylxanthine and rosiglitazone. Cells on the scaffolds were visualized using a confocal microscope. Viability and adiponectin were measured on days 0, 7 and 14. Expression of adipose-differentiation markers was assessed by means of real-time polymerase chain reaction (RT-PCR).Pre-adipose cells attached well onto the silk fibers. The highest initial viability was measured on the low-density scaffolds with expressed VEGF. Adipose-differentiation was evident in visible oil droplets and significantly increased adiponectin protein levels were seen in ELISA. Furthermore, increased expression of adipose-differentiation genes were measured in RT-PCR. Adipose-differentiation was more profound in cells on high-density scaffolds. In concordance, viability of cells on high-density scaffolds did not increase, while that of cells on low-density scaffolds doubled over the 14-day experimental period. Slightly enhanced adipose-differentiation was observed in cells on scaffolds with expressed FGF-2 or VEGF.Silk scaffolds exhibit excellent cytocompatibility for human pre-adipose cells and have application potential in tissue engineering and regenerative medicine. VEGF and FGF-2 expressed on silk fibers could have a potential positive effect on pre-adipose cells, while the effect of VEGF should be further addressed in vivo.

Plasma electrolytic oxidation (PEO), also known as micro-arc oxidation, is a promising electrochemical surface treatment technique for metals which has been used for the generation of various material surfaces and has been the focus of recent biomaterial research. It has been hypothesized that rough PEO surfaces should generally have properties that support cellular attachment and proliferation. However, this has not yet been demonstrated in systematically conducted studies. The present study investigated fibroblast cell proliferation and attachment to ground, electric discharge machining (EDM) and PEO-treated titanium surfaces differing in roughness and porosity.Three surface variants with 'smoother', 'medium-coarse' and 'rough' surface topographies were generated by PEO and EDM on specimens of titanium alloy (with 6 wt% aluminum and 4 wt% vanadium) for comparison with more smoothly ground specimens. The in vitro effects on cellular attachment and proliferation were determined in 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT), 5-bromo-2'-deoxyuridine (BrdU) and live/dead staining assays with L929 fibroblasts cultivated directly on the metal specimens. Cytocompatibility was determined in accordance with DIN 10993-5/-12 regulations by extract assays.Besides cytocompatibility, all PEO specimens exhibited similar biocompatibility and attachment properties, with vital, spindle-shaped adherent cells growing on the surface, regardless of their surface topology. There were no significant differences in cellular proliferation between the different surfaces and negative controls (cells growing in cell-culture plates).With no differences in cellular proliferation and attachment between PEO surfaces with different roughness, we find no evidence to support the notion that rougher PEO surfaces are more favorable for cellular growth of fibroblasts in vitro.

The purpose of the present study was to find inexpensive and non-toxic additives enhancing and accelerating the osteogenesis of mesenchymal stem cells in vitro, which can be used for tissue engineering of bone material.Osteogenic differentiation of rat mesenchymal stem cells was carried-out using classic differentiation medium containing or lacking purmorphamine, statins or oxysterols, respectively. Cell proliferation, alkaline phosphatase activity, calcium sedimentation and expression of bone matrix protein genes were measured to monitor differentiation.Purmorphamine substantially suppressed proliferation, enhanced and accelerated alkaline phosphatase activity and calcium sedimentation and increased the expression of osteopontin and osteocalcin in rat mesenchymal stem cells in vitro. A similar osteogenesis-promoting effect was observed for oxysterols but not for the two statins.Purmorphamine and oxysterols promote and accelerate osteogenesis of mesenchymal stem cells in vitro suggesting their potential application for tissue engineering of bone material.

The present study aimed to find bone substitutes to enhance osteogenic differentiation of mesenchymal stem cells in three-dimensional scaffolds in the absence of dexamethasone.Seven commercial bone substitutes were added to a three-dimensional fibrin-matrix containing rat mesenchymal stem cells in a biocompatible poly-L-lactic-acid mesh. Cell viability, cytotoxicity and alkaline phosphatase activity were followed for three weeks. Expression of bone markers was examined by qualitative evaluation of corresponding transcripts.Six out of the seven bone derivatives exhibited an osteogenic-enhancing effect.The osteogenic-enhancing effect of the evaluated bone substitutes suggests their potential clinical application for preparation of autologous bone replacement material in three-dimensional carriers.

Keratocystic odontogenic tumors (KCOTs) arise from remnants of epithelial structures associated with the development of teeth and occur predominantly intraosseously. In rare occasions they can appear extraosseously in the gingiva as peripheral counterparts; only 15 cases have been reported to date. Evenmore rare are cases of KCOTs of the buccal soft tissues. The aim of this report is to present a rare case of KCOT affecting the buccal soft tissue as an original site and a review of the literature regarding diagnostic and therapeutic options.