0000000000181278
AUTHOR
Vinay Kumar
Associations between single-nucleotide polymorphisms of the VEGF gene and long-term prognosis of oral squamous cell carcinoma.
Department of Otorhinolaryngology, Johannes Gutenberg-University, Mainz, GermanyINTRODUCTION: Functional polymorphisms (SNPs) ofthe vascular endothelial growth factor (VEGF) are asso-ciated with the incidence of oral squamous cell carcinoma(OSCC). An impact of VEGF-SNPs on prognosis of OSCCpatients seems possible. Therefore, correlations betweenprognostic parameters of OSCC patients and five VEGF-SNPs were determined.MATERIALS AND METHODS: In a retrospective long-term study, in 113 OSCC patients that underwentcurative resections, five VEGF-SNPs ( 1154 G/A,+405 G/C, +936 C/T, 2578 C/A, and 460 C/T) wereanalyzed. Associations between SNPs and prognosis(incidence of local recurrent disease, seco…
Osseoconductivity of a Specific Streptavidin-Biotin-Fibronectin Surface Coating of Biotinylated Titanium Implants - A Rabbit Animal Study
Background Biofunctionalized implant surfaces may accelerate bony integration and increase long-term stability. Purpose The aim of the study was to evaluate the osseous reaction toward biomimetic titanium implants surfaces coated with quasicovalent immobilized fibronectin in an in vivo animal model. Materials and Methods A total of 84 implants (uncoated [control 1, n = 36], streptavidin–biotin coated [test 1, n = 24], streptavidin–biotin–fibronectin coated [test 2, n = 24]) were inserted 1 mm supracortically in the proximal tibia of 12 rabbits. The samples were examined after 3 and 6 weeks. Total bone-implant contact (tBIC; %), bone-implant contact in the cortical (cBIC; %) and in the spong…
Nanoporous kaolin – cellulose nanofibril composites for printed electronics
Cellulose nano- and microfibrils (CNF/CMF) grades vary significantly based on the raw materials and process treatments used. In this study four different CNF/CMF grades were combined with kaolin clay pigment particles to form nanoporous composites. The attained composite properties like porosity, surface smoothness, mechanical properties and density properties depended strongly on the raw materials used. In general, higher kaolin content (~80 wt%) led to controllable shrinkage during drying, which resulted in improved dimensional stability of composites, compared to a lower kaolin content (~50 wt%). On the other hand, the use of a plasticizer and a high amount of CNF/CMF was essential to pr…
Nanoporous kaolin
Cellulose nano- and microfibrils (CNF/CMF) grades vary significantly based on the raw materials and process treatments used. In this study four different CNF/CMF grades were combined with kaolin clay pigment particles to form nanoporous composites. The attained composite properties like porosity, surface smoothness, mechanical properties and density properties depended strongly on the raw materials used. In general, higher kaolin content (~80 wt%) led to controllable shrinkage during drying, which resulted in improved dimensional stability of composites, compared to a lower kaolin content (~50 wt%). On the other hand, the use of a plasticizer and a high amount of CNF/CMF was essential to pr…
Evaluation of ultrasound transmission velocity and 3-dimensional radiology in different bone types for dental implantology: a comparative ex vivo study.
Objective To evaluate ultrasound transmission velocity (UTV) for assessment of mechanical bone quality, an ex vivo comparison of different bone types measured with UTV, 2-dimensional (2D) histomorphometry and with 3-dimensional (3D) radiology (cone-beam computerized tomography [CBCT], computerized microtomography [μCT]) was conducted. Study Design Clinical cortical, cancellous, and mixed bone (each n = 6) was measured via UTV (m/s), CBCT (white pixel/black pixel ratio [WP/BP]), μCT (bone volume/total volume [μBV/TV]), and histomorphometry (bone volume/total volume [hBV/TV]). UTV values were correlated with 2D-histomorphometry and 3D-radiologic results. Results For the cortical, cancellous, …
Clinicopathologic conference: Multiquadrant expansile fibro-osseous lesion in a juvenile
This paper intends to present clinical, radiologic, and histopathologic features of a case of gigantiform cementoma manifesting in a 14-year-old boy, without any familial involvement. He has been followed for 3 years. Further cases from the literature have been reviewed that confirm a similar clinicopathologic picture. This is the first case report that describes "non-familial gigantiform cementoma" after the World Health Organisation's classification of 2005.
Implant supported dental rehabilitation following segmental mandibular reconstruction- quality of life outcomes of a prospective randomized trial.
Abstract Purpose The primary objective of this study was to assess the difference in quality of life (QoL) in patients with dental rehabilitation using two or four implant-supported overdentures following segmental mandibulectomy defect reconstruction with fibula free flap. Material and methods This prospective, parallel designed, randomized clinical study was conducted with a 1:1 ratio. At baseline, all participants already had fibula flap reconstruction for segmental defects of the mandible and rehabilitation with conventional (non-implant supported) removable partial dentures. The participants were then randomized into two groups. Group I received implant supported overdentures on two im…
Comparison of conventional twist drill protocol and piezosurgery for implant insertion: an ex vivo study on different bone types.
Objective The aim of this ex vivo study was to compare implant insertion procedures using piezosurgery and conventional drilling in different qualities of bone. Implant bed preparation time, generated heat, and primary implant stability were analyzed. Material and methods Fresh ex vivo porcine bone block samples (cancellous, mixed, and cortical bone) were obtained. The bone quality was quantified by ultrasound transmission velocity (UTV). Each bone sample received three implants of the same diameter using each of the techniques of piezosurgery and conventional twist drills. Time for preparation was taken and the temperature while performing the osteotomy was measured using infrared spectros…
Relation between bone quality values from ultrasound transmission velocity and implant stability parameters--an ex vivo study.
Aim The objective of this study was to determine the relationship between bone qualities measured by ultrasound transmission velocity (UTV) and primary implant stability parameters measured by radiofrequency analysis (RFA) and push-out test (POT) in an ex-vivo model. Materials and methods Three blocks of fresh porcine bone samples were obtained from different anatomic regions, correlating to cortical, mixed and cancellous bone. Mechanical bone qualities of these samples were measured using UTV (expressed in m/s) prior to implantation. Three similar implants (4.1 × 11 mm, AstraTech OS) were inserted into each of the procured bone blocks. The evaluation of implant-bone interface stability was…
Comparison of growth & function of endothelial progenitor cells cultured on deproteinized bovine bone modified with covalently bound fibronectin and bound vascular endothelial growth factor
Objectives The objective of this study was to assess and compare the growth and function of Endothelial Progenitor Cells (EPCs) cultured on covalently bonded Vascular Endothelial Growth Factor (VEGF) and covalently bonded Fibronectin (FN) coating on deproteinized bovine bone (DBB) (test samples), compared to non-modified DBB blocks (control sample). Materials and methods The test samples were prepared by plasma polymerization of allylamine onto DBB blocks. Group1 of test samples were prepared with VEGF coating (VEGF-DBB) where as the Group2 test samples were coated with FN (FN-DBB). Non-modified DBB blocks served as a Control. EPCs were isolated and cultivated from buffy coats of peripheral…
Mobile microscopy as a screening tool for oral cancer in India: A pilot study
Oral cancer is the most common type of cancer among men in India and other countries in South Asia. Late diagnosis contributes significantly to this mortality, highlighting the need for effective and specific point-of-care diagnostic tools. The same regions with high prevalence of oral cancer have seen extensive growth in mobile phone infrastructure, which enables widespread access to telemedicine services. In this work, we describe the evaluation of an automated tablet-based mobile microscope as an adjunct for telemedicine-based oral cancer screening in India. Brush biopsy, a minimally invasive sampling technique was combined with a simplified staining protocol and a tablet-based mobile mi…
Implants in free fibula flap supporting dental rehabilitation - Implant and peri-implant related outcomes of a randomized clinical trial.
Abstract Objectives The objective of this study was to assess the difference in success rates of implants when using two or four implant-supported-overdentures following segmental mandibular reconstruction with fibula free flap. Methods and designs This prospective, parallel designed, randomized clinical study was conducted with 1:1 ratio. At baseline, all participants already had segmental reconstruction of mandible with free fibula flap. The participants were randomized into two groups: Group-I received implant-supported-overdentures on two tissue-level implants and Group-II received implant-supported-overdentures on four tissue-level implants. Success rates of the implants were evaluated…
Osseous response on linear and cyclic RGD-peptides immobilized on titanium surfaces in vitro and in vivo
Biomimetic surface modifications of titanium implants using the Arg-Gly-Asp-sequence (RGD) are promising to accelerate bone healing in cases of medical implants. Therefore, we compared the impact of linear and cyclic RGD (l- and c-RGD) covalently coupled onto titanium surfaces on the osseous response in vitro and in vivo. In vitro, osteoblasts' behaviour on different surfaces (unmodified, amino-silanized (APTES), l- and c-RGD) was analysed regarding adhesion (fluorescence microscopy), proliferation (resazurin stain) and differentiation (RT-PCR on alkaline phosphatase (AP) & osteocalcin (OC)). In vivo, osteosynthesis screws (unmodified n=8, l-RGD n=8, c-RGD n=8) were inserted into the proxim…