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There are two different opinions when it comes to the fabrication of veneers. One group favors the platinum foil technique, the other prefers to apply the veneer directly to the refractory stumps. The following case describes the procedure and preparation of a direct laminated, modified anterior teeth veneer.
We have to understand why veneers are so popular. One reason is that restorations with mostly very thin veneers can be achieved with minimal invasive preparations and yet produce a maximal aesthetic and functional result. The patient has the option to correct the color, function or any flaw without a significant substance loss. Veneers are a kind of restoration that is very gentle and therefore very close to nature.
The veneer bonds to the natural tooth surface and virtually becomes one with the tooth. Indirect lamination methods like the platinum foil technique seem to hinder the work in this case. The direct technique on refractory stumps is the right choice. It allows the dental technician to literally “feel” the restoration. The use of platinum foil for fragile restorations can trick the technician’s eye regarding shape and color. Furthermore, the technician has limited working space to start with and should not have to give up needless space for unnecessary working procedures or fitting methods, because the lamination quality available to you is what you will work with! These statements are not written in stone. They reflect just my opinion and work experience.
Etched and bonded restorations are ideal for anterior restorations. Either feldspathic porcelain veneers or pressed ceramic veneers are normally the first two choices though sometimes there are reasons to choose other materials. In this case, there was a missing tooth requiring either an implant or a bridge. The patient chose a bridge over an implant. Our objective was to find materials that would provide the best esthetics and also conserve the most tooth structure.
Ideally, a pressed ceramic restoration or feldspathic veneer would be used to get the illumination of the underlying tissue. A high strength framework like a zirconia bridge or porcelain to metal bridge, introduces a layer of opaque in the facial aspect of the tooth, and that requires more depth of preparation. In this case, an experimental technique was chosen, which is a hybrid restoration. The facial was cut out of a zirconia framework. The facial half of the tooth was prepped as though it were going to be a pressed ceramic veneer. The lingual half was more aggressively prepped to make room for the zirconia framework. The framework was designed to work like a Maryland Bridge that fits onto the prep, and pressed ceramic was applied on top of that. Small esthetic connectors were fashioned and the restorations still had the illumination and bondability of an anterior allceramic bridge.
I would like to write about one of my recent professional adventures concerning Zirconia. What intrigued me was that it took me down the same road I had been traveling on in the past, posing the same question about the supporting structure, or framework, and its color: should it be colored or white? I have already approached this problem in this very same magazine, because I am sure that the color of the framework conditions everything that is applied on top of it.
Let’s take, for example, a gray and a yellow framework, both metal. Say I have to construct two crowns, A2 coloration Vita, on these two different structures. How will they arrive at the dentist’s office…identical? Absolutely not! Here’s why:
Yellow Metal + Yellow Body = an increase in Chroma
Yellow Metal + Red Body = change of hue – orange
Yellow Metal + Orange Body = change of hue – the tertiary orange-yellow
Gray Metal + Yellow Body = change of hue = green
Gray Metal + Red Body = change of hue and value – reddish gray brown
Gray Metal + Orange Body = change of hue and value – greenish-yellow gray-brown
Physical, technical, and material aspects are covered, with much space being dedicated to clinical cases. The idea is to create a course, a guiding thin red line in understanding the dynamics that lead to and control success using this fascinating material. It is not by chance that the route I have chosen is of daily practice in a small provincial laboratory, without large amounts of outside help or being either a large company or big sponsor, but all the more credible and closer to reality for most of us because of this.
There is now an argument clearly relevant to every day life, that is, the increasingly widespread and pressing use of the concept of ESTHETICS in all areas of life in this era of global communications. It is a challenge to be met head on. In fact, the demand for the best esthetics is above all pertinent to the field of dentistry and to the dental technician because esthetics in the mouth has become more than ever before an extraordinary instrument of communication and social relationships.
The smile has an important value in transmitting messages between individuals, above all the nonverbal ones, and are part of the very personal “body language” that everyone activates when communicating with others. Any social interaction is prepared or accompanied by a smile that will be all the stronger and more important the more its overall appearance is seductive and pleasing (translated literally from the Latin, if shining brightly leads the way, it brings results).
It is commonly understood that a lack of confidence in the business world is exacerbated by embarrassment about the color, shape or alignment of our teeth. A self-assured attitude is helpful in our day-to-day dealings with the public, if we expect to have success. This seems to be especially true with any type of sales or speaking position. A smile can speak volumes about overall appearance and the care we take with our health.
Our patient, a male in his early 40’s, was experiencing discomfort with his appearance when dealing with professional contacts, especially since he worked in the dental field. He was aware that his two centrals were discolored, uneven and poorly contoured. He had decided that it was time to change his smile’s appearance. He approached his clinician about the possibilities of changing his two aged crowns on teeth numbers 8 and 9.
CAD/CAM and esthetics are not polar opposites. They enhance each other to create esthetic results that are also remarkable for the durability of their framework units and veneer ceramics. The important prerequisites for planning and execution of a high-quality prosthetic restoration are knowledge of the physical properties of the different framework materials and of veneer ceramics. How to exploit the esthetic options of veneer ceramics to the utmost is something you can learn and develop through your own individual options. Modern ceramic materials generally offer a wide range of options when you want to customize your esthetic solution. Ralf Dahl CDT sees the Initial ceramic system as one of the best solutions when fabricating esthetic natural-looking ceramic restorations. The ceramics are layered in a logical sequence to exploit their individual strengths and are very future-oriented by reason of their creative potential. But do we utilize this versatility to the full and in a proper manner? Ralf Dahl has his own ideas on the use of CAD/CAM and ceramics and presents us with his technical solutions by way of case reports.
Porcelain had already been discovered in China by the 7th century. But it was in 1708 – more than 1,000 years later – before Europe managed to unravel the secret of Chinese porcelain with the invention of “European porcelain” by Friedrich Böttger.
Another 100 years went by before Ash fabricated metal ceramic in England in 1838. Then the development intervals for new innovative ceramics progressively shortened. The all-ceramic era began with the development and manufacture of the first ceramic inlay in 1857. Then, one after another, new products were introduced: Dicor glass ceramic, In-ceramic, Empress 1 and Empress 2, E-max, overpress ceramics and many different veneer ceramics.
Pure sintered ceramic has established its place in dental technology over the years as a physically and esthetically premium veneer ceramic. Furthermore, through appropriate duplication systems and controlled refractory investment materials, we are now able to fabricate high precision all-ceramic full and partial crowns, veneers and inlays that can mimic the natural tooth build-up. In 1965, McLean and Hughes developed oxide-reinforced ceramic and doubled its strength in subsequent versions.
Later, in England, Ron Garbie arrived at the idea of mixing zirconium oxide with yttrium oxide. This increased the structural strength through stabilization of the phase transformation in the texture. The flexural strength and breaking strength matched those of steel. These materials have established themselves in dental laboratories since the mid-1990’s. The pioneer in this field of structural all-ceramics has certainly been the In-Ceram method which involves a glass-infiltrated oxide ceramic. The increased strength of this product is due to infiltration of lanthanum glass.
Article two provided the basics of fulcrums and levers, explaining the psychics that relate to curves and how they apply to one dimension relating to the mechanics of the curve of Spee. In this article we will add the remaining curves that will complete the vertical dimension. We will also examine a true vertical system that has association to all the components of the vertical axis, while illustrating how the mandible operates within these curves.
The purpose of these articles and lectures is to emphasize that the human body is not a machine, but functions to the same principles of mechanics. The added factor is that we are biological, and this aspect is dealt through medicine and medical science. Our role as technicians in the treatment team is to complete the mechanical aspect in collaboration with the biological aspects that the clinician prescribes and deals with.
The role of the clinician should provide everything to us to complete the technical aspect of the treatment, including the construction and the mechanical things that go on. That must include their understanding of what that entails and what we as technicians are going to need. What we should be able to do then is imagine that our articulator is surrounded by muscles that will move and control what we are about to make. We need to understand and have knowledge of the muscles that are present in this system. (I will deal with this aspect as a complete article when we get to 3D dental space.) Then, if the mechanics, the physics and the biology work is understood in finite detail, one should be able to make a reconstruction function perfectly to the clinician’s prescription for the patient. The medical attachment from then on should be perfect and not destructive in any way.
For the past 29 years, I have worked as a dental ceramist in different parts of the world, making teeth to replace or enhance nature’s inadequacies, people’s lifestyle, or accidents. In the realm of teeth, I suppose you could say that I have probably seen it all. From the desperate results of inferior work to incredible dental miracles in which a beautiful, healthy smile now exists where disease and destruction once threatened. Consumers are learning more and more about the role that they play in both their medical and dental health. The desires and interests of patients are driving the decisions of doctors and dentists today.
Within this environment comes the need for information about options, products and the possible implications of dental care decisions. There are many differences in quality that exist in the dental field today. Today’s informed consumer wants to know how to get what they want – the first time. Our obligation to the patient is to ensure that the journey to their final destination is one of good thoughts and enjoyment. Doing everything possible to communicate freely with the patient and allow the patients to express themselves. So, that brings up the subject of communication. People use different key words in an attempt to communicate. But just what does “white”, “natural”, “straight”, “big”, “small” mean to the patient that you are talking with at that particular time?
Do these words have the same meaning from patient to patient, dentist to dentist and dental ceramist to dental ceramist? For example, if a dentist sends the same case with the same instructions to several different laboratories he will get extremely different looks. Each laboratory interprets the same request with a different vision. The biggest questions that a restorative dentist should ask is: “Which outcome will my patient like?” and “What kind of tooth preparation will this desired outcome require?” Each vision will have different requirements for tooth preparation. Communication is a complex issue, yet as in the rest of life, an essential part of a satisfactory outcome. There are specific tools that can be used to assist in a consistent message traveling between everyone involved, so that the desired outcome can be achieved with no surprises for anyone. The first step, no matter what type of enhancement is required is diagnosis and treatment planning.
Automated engineering and manufacturing are no longer unimaginable in handicraft fields; they began to penetrate years ago. In dental technology, however, where every restoration is unique, it was hard to imagine until recently that CAD/CAM technology belonged in the laboratory. But zirconia and the extremely rapid development of computer software and hardware changed all that. This process for automating labor-intensive routine jobs has become highly competitive on the global market. The case report below teaches us that this technical progress is no longer weighed down with huge investments—the dental laboratory can outsource part of its fabrication process to a milling center.Case Report
The patient, an 18 yr-year-old student, suffered from aplasia of both lateral maxillary incisors (Fig.1). The original treatment plan proposed to her was to treat the edentulous areas with single implants. After the orthodontic treatment was complete, it was discovered that implants would not be possible because of the angulations of both canines and the resulting convergence of the roots of the central and lateral incisors. The patient was then treated with an intermediate partial denture to replace teeth 7 and 10, which of course badly compromised her esthetic appearance. It constituted a severe emotional handicap for a girl of her age (Fig. 2). Since the patient was offered no satisfactory solution, she decided to change dentists. What treatment options would you now consider for her?
Every patient is different. You have to constantly train your eyes and constantly motivate yourself to respect that individuality. The book Atlas of Anatomy: The individuality of the Natural Tooth should become the basis for motivating ourselves—accepting the fact that mixing creativity and hard work is what we must do ourselves. In this conversation, author Knut Miller tells us how to work with his book and how to develop a feel for teeth – whether you are a novice, intermediate or advanced technician.
Talking about esthetics is like traveling within a complex dimension where the danger of loss of contact increases with any type of reality that suggests treatments, concrete objectives, functionality. The goal of this article is to motivate the reader to make esthetic success predictable, apart from decisive variables associated with individual talents.
In etymology, esthetics is defined as the “science of the beautiful” and describes everything that relates to the senses. In our profession, esthetics proceeds from a free search for beauty to the art of “mimetics.” Mimetics is a Greek word and describes the art of exact reproduction of the natural model – in other words the capacity to imitate. Imitating nature means giving a certain adaptability to the art work that you create. And adaptability in turn describes the ability to perceive shapes and colors in the environment.
The natural model then represents the archetype – the unchangeable form, the harmony, the center around which the reality of our treatment is defined, in other words myth (Fig. 1).
Imitating truth means comparing our personal representation with the unchangeable form. The product of our treatments is a synthesis of this model, i.e. of the natural tooth and the different clinical situations. Although myth suggests something fleeting, distant, and unreachable, it can entice us and move us emotionally to search for harmony in what we do, and thereby overcome our inner conflicts and problems (Fig. 2).
In Part I of Mimesis: Imitation and Interpretation of a Natural Tooth Through Shape & Colour the author, Giovanni Paolo Miceli, presented a young lady who without the presence of functional pathologies, chose to visit a dental clinic for esthetic reasons. Part I of Mimesis began with a look at the importance of image processing and concluded with Fig. 41 which presented the application of the clear stain.
Form plays an important role in the field of restorations because it is the first thing that patients perceive, as compared to stratifications, which are mainly perceived by dental operators.(Figs. 89, 90) (bib., 2, 3, 11, 13)
The patient in fact, will show little interest in the effects inserted in a tooth, but will show disappointment in the shape of a form that is not deemed appropriate.
Therefore, prior photography and image retouching play an important role when studying and understanding a patient’s response to various esthetic solutions. When carrying out the practical phase of modeling a dental restoration in composite, most of the work is done with a spatula. (figs. 22 through 48)
For practical reasons due to the nature of the materials, shaping with a mill is kept to a minimum, and should only be used for structuring surface characteristics in the artificial restoration. As far as morphological carving is concerned, the following technical steps are particularly important:
• morphologically accenting the three-dimensional effects by accurately carving the parts of the incisal margins that are in shadow. (fig. 56) (bib.3, a6, 10, 11, 12, 14)
• transition zones of passage between adjacent surfaces and vestibular areas.
• The shaping of inter-incisal triangles between each tooth to render them similar to corresponding areas in natural teeth. (figs. 57, 58)
• Carving and sculpting the surface of the restoration. (figs. 62, 66)