ABSTRACT
Objective: Maintaining the health of oral tissues is a major goal in dentistry. However, limitations in dental materials, instruments, procedures and medications prevent achievement of this goal. Advances in nanotechnology have paved the way to approach this goal. This study reviews the advances on nanotechnology in dentistry
Review of Literatures: In this review study, Google Scholar, PubMed, Science Direct, Medline and Cochrane databases were searched for relevant English and Farsi papers from 1981 to 2013. The searched key words were: "nano-characterization", "antimicrobial agent", "nano-dentistry", "nanotechnology", "nanoparticles", and "nano-medicine"
Conclusion: Studies indicated extensive applications of nanotechnology in various fields of dentistry such as prevention, diagnosis and treatment. Use of nanoparticles as antimicrobial agents in conjunction with other oral hygiene tools such as toothpastes may prevent many oral and dental conditions. Also, application of nanostructures enables faster and easier detection of oral cancers and assessment of the saliva for presence of viruses, proteins or specific markers. Last but not least, nano-capsules, nano-coatings and nano-antibiotics enable more efficient treatments
ABSTRACT
Atomic force microscopy [AFM] is a three-dimensional topographic technique with a high atomic resolution to measure surface roughness. AFM is a kind of scanning probe microscope, and its near-field technique is based on the interaction between a sharp tip and the atoms of the sample surface. There are several methods and many ways to modify the tip of the AFM to investigate surface properties, including measuring friction, adhesion forces and viscoelastic properties as well as determining the Young modulus and imaging magnetic or electrostatic properties. The AFM technique can analyze any kind of samples such as polymers, adsorbed molecules, films or fibers, and powders in the air whether in a controlled atmosphere or in a liquid medium. In the past decade, the AFM has emerged as a powerful tool to obtain the nanostructural details and biomechanical properties of biological samples, including biomolecules and cells. The AFM applications, techniques, and -in particular- its ability to measure forces, are not still familiar to most clinicians. This paper reviews the literature on the main principles of the AFM modality and highlights the advantages of this technique in biology, medicine, and- especially- dentistry. This literature review was performed through E-resources, including Science Direct, PubMed, Blackwell Synergy, Embase, Elsevier, and Scholar Google for the references published between 1985 and 2010
ABSTRACT
PURPOSE: Various bone graft materials have been used for periodontal tissue regeneration. Demineralized freeze-dried bone allograft (DFDBA) is a widely used bone substitute. The current widespread use of DFDBA is based on its potential osteoinductive ability. Due to the lack of verifiable data, the purpose of this study was to assess the osteoinductive activity of different DFDBAs in vitro. METHODS: Sarcoma osteogenic (SaOS-2) cells (human osteoblast-like cells) were exposed to 8 mg/mL and 16 mg/mL concentrations of three commercial types of DFDBA: Osseo+, AlloOss, and Cenobone. The effect of these materials on cell proliferation was determined using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. The osteoinductive ability was evaluated using alizarin red staining, and the results were confirmed by evaluating osteogenic gene expression using reverse transcription polymerase chain reaction (RT-PCR). RESULTS: In the SaOS-2 cells, an 8 mg/mL concentration of Osseo+ and Cenobone significantly increased cell proliferation in 48 hours after exposure (P<0.001); however, in these two bone materials, the proliferation of cells was significantly decreased after 48 hours of exposure with a 16 mg/mL concentration (P<0.001). The alizarin red staining results demonstrated that the 16 mg/mL concentration of all three tested DFDBA induced complete morphologic differentiation and mineralized nodule production of the SaOS-2 cells. The RT-PCR results revealed osteopontin gene expression at a 16 mg/mL concentration of all three test groups, but not at an 8 mg/mL concentration. CONCLUSIONS: These commercial types of DFDBA are capable of decreasing proliferation and increasing osteogenic differentiation of the SaOS-2 cell line and have osteoinductive activity in vitro.