Griggs , Ph. Author information Copyright and License information Disclaimer. Copyright notice. The publisher's final edited version of this article is available at Dent Clin North Am. See other articles in PMC that cite the published article. SYNOPSIS The past three years of research on materials for all-ceramic veneers, inlays, onlays, single-unit crowns, and multi-unit restorations are reviewed.
Table 1 Methods of forming ceramics for all-ceramic prostheses. Open in a separate window. Slip Casting A slip is a low viscosity slurry or mixture of ceramic powder particles suspended in a fluid usually water. Hot Pressing The lost wax method is used to fabricate molds for pressable dental ceramics.
Table 2 Common topics for in vitro dental ceramic studies — Figure 1. Strength distributions for prostheses fabricated from two hypothetical dental ceramics. Figure 2. Figure 3. Figure 6. Table 3 Clinical studies reporting longevity of all-ceramic restorations. Figure 4. Figure 5. Anusavice KJ. Recent developments in restorative dental ceramics. J Am Dent Assoc. Deany IL. Recent advances in ceramics for dentistry. Crit Rev Oral Biol Med.
Systematic review of ceramic inlays. Clin Oral Investig. Kelly JR. Dental ceramics: current thinking and trends.
Ceramics in dentistry: historical roots and current perspectives. J Prosthet Dent. Martin N, Jedynakiewicz NM. Dent Mater. McLean JW. Evolution of dental ceramics in the twentieth century. Mormann WH, Bindl A. Porcelain veneers: a review of the literature. J Dent. Piddock V, Qualtrough AJ. Dental ceramics--an update. Qualtrough AJ, Piddock V. Ceramics update. Raigrodski AJ. Contemporary all-ceramic fixed partial dentures: a review. Contrast ratio of veneering and core ceramics as a function of thickness.
Int J Prosthodont. Fracture resistance of three all-ceramic restorative systems for posterior applications. In vitro marginal fit of three all-ceramic crown systems. American Association for Dental Research. Orlando, FL: Reliability model for framework ceramic with multiple flaw populations.
Structural reliability of alumina-, feldspar-, leucite-, mica- and zirconia-based ceramics. Sundh A, Sjogren G. Fracture resistance of all-ceramic zirconia bridges with differing phase stabilizers and quality of sintering. In-Ceram failure behavior and core-veneer interface quality as influenced by residual infiltration glass. J Prosthodont. The strengthening mechanism of resin cements on porcelain surfaces.
J Dent Res. Its rapid hydrolyses produces calcium deficient hydroxyapatite [ ]. Alumina is very inert and resistant to corrosion in an in vivo environment [ ]. It elicits minimal response from the tissues, and remains stable for many years of service. Few minutes after the implantation of alumina device, proteins and other biomolecules adsorb on its surface, to form a fibrous capsule around the implant that protects it from immune system.
The fact that alumina is biocompatible does not mean that tiny particles formed by the implant wear cannot generate a significant foreign body reaction [ ]. It is extremely hard and scratch-resistant 9 on the Mohs scale, next only to diamond. It has excellent corrosion resistance in vivo environments Figure However, the most disabling property of alumina is its brittleness high elastic modulus , hence the need to optimize the composition, the porosity and the grain size to improve the mechanical properties of alumina, such as strength, fatigue resistance and fracture resistance.
Because of the better resistance to fracture and the higher bending strength Thus, a typical alumina implant is made of single crystal alumina cylindrical core around which polycrystalline alumina is fused. Currently, alumina dental implants are declining in popularity and being replaced by other material having better properties [ ]. Nanoporous alumina fabricated using the anodization process left and center.
Osteoblast interaction with the nanoporous architecture right [ ]. The demand for zirconia dental implants are increasing recently. In comparison with the Ti dental implants, their increased esthetic, due to similarity to the human tooth color, is the main benefit of these implants [ 88 , ].
Zirconia with better optical, esthetic, mechanical and biological qualifications, is a hopeful substitute to traditional Ti implant system for oral recovery [ ], and is produced by the oxidation of zirconium [ ]. Zirconium, which is a transition metal [ ], with gray white color [ ], can be used to make zirconia implant. Segments of the metal implant can be uncovered by recession of gingiva and the loss of apical bone, which this can disclose a discolored overlying gingiva [ ].
These concerns make an opportunity to use the zirconia ceramics because they enjoy great esthetic, biological and mechanical characteristics and they also lack electrically corrosion.
Polyethylene and Ti show more inflammatory reactions than zirconia. Less inflammatory response along with the lack of mutagenicity and toxicity in zirconia, can be considered as the most attractive zirconia properties [ ]. Indeed, zirconia owes its importance to the stress-induced transformation of the metastable tetragonal crystallites phase into monoclinic phase, when it is localized around a propagating crack. Hydroxyapatite is a bioceramic of great clinical interest due to its nontoxicity, bioactivity, good biocompatibility, osteoconductivity, and its non-inflammatory nature.
However, since it has a high elasticity modulus brittle , hydroxyapatite is usually associated to other materials to form an implant in load-bearing applications. In fact, implants for load bearing, such as titanium screw, can be coated with hydroxyapatite. The application of hydroxyapatite coatings is an interesting surface amendment on dental implants [ ]. As its coatings apply on implanted material, it provides enough calcium and phosphate ions at initial implantation stage and makes the implant material biocompatible [ ].
The properties of hydroxyapatites are given in Table 4. Properties of hydroxyapatites coat [ ]. However, hydroxyapatite has osteogenic nature and is able to form strong bond with host tissues, so it is widely used in biomedical field for osteointegration, bone replacement and regeneration, coating metallic implants, and to fill the defects generated in bones [ ].
Despites their benefits, all ceramic dental materials and their applications shows challenges which still need to be tacked. The challenges in dentistry remain in understanding and improving the clinical performance of the biocompatible restorative materials by improving definition of failures, laboratory testing, and clinical studies.
In fact, material factors, including differences in thermal conductivity and coefficient of thermal expansion between core and veneer, likely create residual stresses that redispose a restoration to chipping.
Only requirements of patients further complicate the challenge of understanding factors that contribute to long term success of restoration. In this context, some works include report patient or provider factors or patient control groups.
Few recent works [ , ] have been reported on clinical trials. Several improvements have been recently made in structural reliability via damage tolerance and flaw control [ , ].
Predictive laboratory tests can reduce the need for expensive and time-consuming clinical tests, which sometimes exceed the commercial lifetime of the materials being evaluated. In addition, laboratory tests, likely over estimate clinical lifetimes, can replicate clinical failure modes. Several parameters like dimensional accuracy, surface, and mechanical properties of ceramic dental materials should be improved to obtain high quality final products [ ].
Another challenge is bacteriological safety of the final products which are in contact with human organs and tissues. However, it is necessary to make sterilized protocols while keeping intrinsic properties [ ]. In addition, Lee et al. Hence, the porosity of the ceramics is another challenge in dentistry.
It has been showed that the porosity was reduced by adding dopants or viscous liquid forming phase, choosing the corresponding powder granulometry, and applying HIP to the green body [ ]. Several studies revealed that the surface quality of ceramic materials depends strongly on the technique, raw material characteristics, and processing conditions [ , ]. Moreover, there maining challenges for future advances are present abundant arenas for future innovations. Moreover, it will be important to determine where and how informed simplifications in testing conditions can be made.
Machining techniques and design methods should to be improved and innovated to achieve good ceramic restorations with subsurface damage and little surface. CAD and CAM and fabrication processes creating veneers and cores separately will further evolve [ ]. Thus, these approaches will be complemented by additive approaches, laying down materials only in places where it is needed to create a restoration [ ].
However, these approaches have shown significant substantial hurdles. For over years, ceramic materials have been utilized in dentistry. This chapter shows that dental ceramics can be fabricated by different techniques. Dentistry as an art of oral health is one of the major affiliates of dental science. Operative dentistry continues to evolve toward bright future with the innovations and development of new materials, techniques, and equipments. Several numbers of dental ceramic materials have been developed with respect to strength, survival, applications, and esthetics.
The success of dental ceramic materials depends on various factors like design, type of material, cementation media, clinical data, etc. These factors help the dentist to enhances the relation between laboratory studies and clinical data and to choice the appropriate ceramic material. Although the remarkable evolution of ceramics in dentistry not all the challenges have been solved. We would like to thank the Author Service Manager Mrs. Mia Vulovic for his time and support.
We also thank our institutions for give us support. Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution 3. Help us write another book on this subject and reach those readers. USES Laminate veneers and full crowns for anterior teeth Inlays, Onlays and partial coverage crowns Complete crowns on posterior teeth.
Potential to fracture in posterior areas Need for special laboratory equipment such as pressing furnace and phosphate bonded die material Inability to cover the color of a darkened tooth preparation or post and core since the crowns are relatively translucent.
Compressive strength and flexural strength lesser than metal-ceramic or glass-infiltrated In-Ceram crowns. Fabrication is similar to IPS Empress It is made from a lithium disilicate framework with an apatite layered ceramic.
This system consist of 2 components 1. An improved high aluminous porcelain system termed In-Ceram was developed by Dr. In-Ceram Crown process involves three basic steps : Dense core is made by slip casting of fine grained alumina particles and sintered. The sintered alumina core is infiltrated with molten glass to yield a ceramic coping of high density and strength. The infiltrated core is veneered with feldspathic porcelain and fired.
Wear of opposing teeth is lesser than with conventional porcelains. Improved esthetics due to lack of metal as substructure. Biocompatible, diminished plaque accumulation, biochemical stability.
Slip casting is a complex technique and requires considerable practice. Due to the comparatively high opacity of the alumina core, this material was introduced. USES Anterior inlay, onlay ,veneers and anterior crowns. Not in high stress region The In-Ceram technique was expanded to include its modified form with zirconia. A mixture of zirconium oxide and aluminum oxide is used as a framework material, the physical properties were improved without altering the proven working procedure.
Until , indirect ceramic dental restorations were fabricated by conventional methods sintering, casting and pressing and neither were pore-free. The tremendous advances in computers and robotics could also be applied to dentistry and provide both precision and reduce time consumption. With the combination of optoelectronics, computer techniques and sinter-technology, the morphologic shape of crowns can be sculpted in an automated way.
Restoration design is the process of creating the wax pattern Restoration design is done by the computer — either with interactive help from the user or automatically. Restoration fabrication includes all the procedures from dewaxing upto the final casting lost wax technique Restoration fabrication includes machining with computer controlled milling machines, electrical discharge machining and sintering CAD CAM Uses digital information about the tooth preparation or a pattern of the restoration to provide a computer-aided design CAD on the video monitor for inspection and modification.
The image is the reference for designing restoration on video monitor. Once the 3-D image for the restoration design is accepted, computer translates the image into a set of instructions to guide a milling tool computer-aided manufacturing [CAM] in cutting the restoration from block of material. Computerized surface digitization 2. Computer - aided design 3. Computer - assisted manufacturing 4. Computer - aided esthetics 5. Computer - aided finishing CEREC 1 The main change or revolution in the hardware of Cerec 1 machine was the introduction of an electrically driven milling machine with a more efficient cutting disc.
Clinical shortcomings of Cerec 1 system Although the CEREC system generated all internal and external aspects of the restoration, the occlusal anatomy had to be developed by the clinician.
Inaccuracy of fit or large interfacial gaps. Clinical fracture related to insufficient depth of preparation. Relatively poor esthetics due to the uniform colour and lack of characterization in the materials The milling machine was replaced with multihead version incorporating two cutting heads with a total of of freedom Enlargement of the grinding unit from 3 axes to 6 axes.
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