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Biological Applications of Diamond
Published in James C Sung, Jianping Lin, Diamond Nanotechnology, 2019
With the development of CVD, diamond coating is an attractive method to improve the cutting performance and tool life. Jackson and coworkers12 used hot filament CVD (HFCVD) technique to coat tungsten carbide (WC-Co) dental burs with diamond film and examined the cutting performance of these dental burs by drilling materials such as borosilicate glass, acrylic teeth, and natural human teeth. Figure 8.9 shows the dental bur drilling machine. Figures 8.10 show that diamond film is uniformly coated onto the cylindrical substrate surface after HFCVD. After drilling human tooth materials, the tooth materials such as dentine clog interstices on the bur, reducing its abrasive performance. The life of the burs was measured by comparing the amount of flank wear of dental bur. Figure 8.10(C) shows that HFCVD diamond bur has the best performance. These experiments show that HFCVD diamond coated dental bur gives longer bur life and a much better quality of drilling and machining.
Biology Related Experiments
Published in Eli Ruckenstein, Gersh Berim, Wetting Experiments, 2018
Hydroxyapatite (Ca10(PO4)6(OH)2) forms the major constituent (∼95%) of the outermost part of the human tooth enamel (surface enamel). The actual tooth contains 1% of organic material which also play an important role in the salivary adsorption processes. However, here we illustrate our procedure with pure hydroxyapatite. To identify the adsorbed species on hydroxyapatite coated germanium internal reflection elements by multiple internal reflection infrared spectroscopy, the apatite coating must be considerably thinner than the depth of penetration of the infrared beam. The depth of penetration (dp) of the beam can be calculated from (10)dp=λ12π(sin2θ−n212)1/2,
What Have We Learnt From the Nature and History?
Published in Rajendra Kumar Goyal, Nanomaterials and Nanocomposites, 2017
Dentin is the naturally occurring hybrid material containing apatite and fibrils of type I collagen. It is the most abundant mineralized tissue in the human tooth. It is found beneath the enamel layer in teeth. It is a fiber reinforced composite material containing ∼50% carbonated apatite and 30% organic matter (i.e., type I collagen). It has fiber-like tubules that provide reinforcement to the surrounding matrix. The lining of these tubules is composed of a highly mineralized cuff of intertubular dentin containing mostly small apatite crystals. The crystals are needle like near the pulp becoming more plate like closer to the enamel. Unique nanostructures of bones provide excellent interaction between the proteins and the bone cell in the body and also impact ability to absorb the impact load. Moreover, bones behave like a spring which can change shape on deformation within limit without cracking, to shorten and widen in compression and to lengthen and narrow in tension. If the load imposed exceeds the bone's ability to deform elastically, it can deform further and change shape permanently by plastic deformation. If both the elastic and plastic zones are exceeded, the bone fractures. Thus, bone is the material which shows good stiffness and strength along with flexibility and light weight due to its unique nanostructured design [21].
Comparison of clinical efficacy of three different dentin matrix biomaterials obtained from different devices
Published in Expert Review of Medical Devices, 2023
Robert Dłucik, Bogusława Orzechowska-Wylęgała, Daniel Dłucik, Domenico Puzzolo, Giuseppe Santoro, Antonio Micali, Barbara Testagrossa, Giuseppe Acri
In implant dentistry and restorative surgery, bone augmentation procedures are routinely used nowadays to treat patients with bone defects. In addition to the broadly available bone substitute materials [1], autogenous bone graft can be successfully used, as it has a specific advantage over other bone substitutes owing to its osteogenic properties [2]. However, donor graft harvesting requires an additional procedure at the donor site, which, despite the low morbidity, is associated with an increased treatment time [3]. Therefore, in the last years, the use of ground natural teeth, until recently considered as a waste material, was evaluated. From 1993, Kim et al. started experimental studies using teeth as graft material [4]. The human teeth are composed of four tissues – enamel, dentin, cementum, and dental pulp. Due to the very similar chemical composition of dentin and bone, it seems to be a very promising augmentation material. Dentin in approximately 70% is composed of inorganic hydroxyapatite crystals, in about 20% of organic extracellular matrix, mainly collagen type I and in ~10% of water [5–7]. In addition, dentin contains bone morphogenetic proteins (BMP) [8], which belong to the transforming growth factor beta (TGF-β) superfamily, which, as demonstrated for the first time by Urist [9], are able to stimulate osteogenesis. Many researchers have reported that demineralization of dentin is necessary for the release of osteoinductive growth factors trapped in dentinal tubules [10]. Several methods exist for preparation of the demineralized dentin matrix (DDM). Universally, after extraction, the patient’s tooth must be cleaned of all calculus residues, soft tissues, and any foreign material. Secondly, the tooth is crushed into small particles, grinded by a special mill, and soaked in demineralizing reagents. DDM provides a scaffold to support the bone regeneration process [5]. In 2009, the first transplant with autogenous tooth graft material (AutoBT, Korea Tooth Bank Co., Seoul, Korea) was performed with no reported complications [11]. In an experimental study in 2010, the demineralized dentin matrix was obtained with a hand-operated apparatus for crushing teeth and showed the induction of bone and cartilage [12]. In a clinical study on 190 patients treated with powder-type auto-tooth bone graft material, obtained with an unspecified technique, it was concluded that it induced good bone generation through its osteoinductive and osteoconductive capacity [13]. In 2014, the results of a study on a group of 15 patients were published, demonstrating excellent healing after augmentation with autogenous teeth [14]. Based on the successful demonstration of the positive role of dentin particulate in alveolar ridge preservation [4,11,14], the availability of specific devices, able to produce tooth-derived material in a safe and reproducible way, was felt.