COSMETIC DENTISTRY

1. What does the term “Cosmetic” stand for?

The term “cosmetic” refers to Aesthetics which is a philosophical concept that describes everything “beautiful than man can perceive with his senses” and was introduced for the first time by the German philosopher A.G. Baumgarten in 1735. It is, however, very difficult to define “beauty” with objectivity, and this is why this concept is rather a subjective one. Since ancient times there has been a controversy regarding what is “beautiful”. Socrates argued that nice coincides with good, which subsequently both coincide with useful. On the contrary, Plato believed that artists, who are the main expressors of “beauty” just represent, imitate something that is artificial or natural, and only when this imitation is combined with thought it can reach its superior form. The only certainty is the fact that, from ancient times till today, there is an indefinable attraction of man to the search of beauty.

2. Which is the field of cosmetic dentistry?

“Cosmetic dentistry” consists a sector of classical dentistry that deals with the improvement of the appearance of teeth, gums and more generally of the oral and jaw area and is rapidly developing. Both the desire of a person for a beautiful smile and the progress of the technology of dental biomaterials and of the applied techniques, contribute to its rapid development. The mouth area consists 1/3 of the overall area of the face, but it is, perhaps, more important for the image a person has for his/her appearance, as it is a zone which performs a group of kinetic functions. Vital functions such as chewing, communication, speech-articulation, the expression of feelings and sometimes respiration, are performed by the mouth. Research has shown that psychology, self-confidence, insecurity, sociability, self-esteem, stem from the smile. A research that was performed in 2004 by the American Academy of Cosmetic Orthodontics has shown that 75% of the respondents believed that the advancement in their workplace also depends on an attractive smile.

3. Which people does cosmetic dentistry regard?

Undoubtedly, cosmetic dentistry regards everyone. It was formerly erroneously believed, that aesthetics depends on age. However, it is particularly pleasing that, lately, the average age of patients that desire to have a “beautiful” smile is significantly increasing. They do not just wish to restore their chewing capacity, but also to improve the overall appearance of their mouth.

4. What is beautiful, from an aesthetic point of view, and for dentistry?

Whatever imitates and represents something natural and contributes to the normal function of the oral and jaw system (useful). Teeth are not by design unicolor, opaque, white or aligned in perfect symmetry (which is the case in the so-called Hollywood style). They are a complex canvas of color gradations, opacifying, different crystal dental structures that compose a result in combination with the refraction, absorption and reflection of light. Undoubtedly, aesthetics coincides with harmony. The color, shape, size of the teeth must be harmonized with the surrounding soft tissues and the type of the face. The term of the “golden ratio” exists in dentistry too, as well as the use of the famous number φ=1.618. It refers to the ratio of the width of the central area to the width of the lateral area and respectively the width of the lateral area to the cuspid teeth, composing thus the aesthetic dental ratio. The overall width of the front teeth to the width of the maximum smile in a ratio 1/0.618 ensures the aesthetic efficiency of the smile.

5. Which are the requirements of cosmetic dentistry

Cosmetic dentistry requires a fully prepared treatment plan, for the development of a relationship of confidence and cooperation between the therapist and the patient. The treatment plan must follow a holistic approach and must be fully personalized. It is based on the three principles of diagnosis-prevention-treatment, it is prepared after an extensive discussion with the patient through which his/her desires and requests are determined as well as to what degree the latter are realistic. The therapeutic part, the periodontal and root canal treatment (resection), are always performed before the cosmetic part.

6. The periodontal treatment that precedes, has only a therapeutic purpose?

Periodontal health and, therefore, the periodontal support of teeth are the foundations in order to achieve an aesthetically beautiful result and to carry out, without any problems, the treatment plan. A beautiful smile always stems from a healthy, clean mouth. The first step toward cosmetic restoration is undoubtedly the cleaning of teeth. Accumulations of microbial dental plaques, calculus-tartar, soft, red, irritated, swollen gums, form an ugly scenery. The sector of periodontology deals with a multitude of interventions that are related with the soft tissues and can improve the aesthetic image of the mouth. One of these is the treatment of the “gummy smile”, the effect of the image of the prominent gums that cover the upper jawbone (maxilla) when a person is smiling.

7.What is the importance of the endodontic treatment before the cosmetic restoration?

Depending on the type and the reason of the cosmetic restoration, in order for the restoration to succeed, it is very important that the dentist evaluates the endodontic condition of the tooth. Cosmetic restorations that clearly regard the improvement of the smile (for example  veneers, whitening) usually require endodontic treatment. On the contrary, the good aesthetic results of therapeutic actions always require an excellent endodontic treatment. Teeth that will be restored with crowns due to fractures, extensive loss of dental tissues (chipping due to bruxism, corrosion) and dental caries must be evaluated regarding their vitality or whether and how much the pulp has been infected. Many times, even when a tooth is dentally drilled, particularly the front lower teeth, the pulp-nerve of the tooth is irritated which initially results to inflammation and subsequently to necrosis.

It is better that the root canal treatment-resection is performed properly and accurately by a root canal specialist before the final adhesion, if it is necessary, and not afterwards, as the crown will have to be perforated and part of the porcelain will be consequently destroyed.

8. What is the use of lasers in cosmetic dentistry?

Lasers are particularly valuable for medicine. They have multiple uses in dentistry, some of which are tooth whitening, hemostasis, as well as the arrangement of the gum tissues.

In tooth whitening, the light emission frequency of the laser acts as a photocatalyst in the respective chemical reaction, which accelerates the process and the produced visible results.

The action of the laser is based on the sublimation of cellular fluids, and thus it is a totally bloodless operation, causing, on the contrary, hemostasis, and it is painless, aiding the rapid healing process. It is thus particularly useful in cases where the gums have “covered” the healthy tooth and need to be removed so that the tooth is exposed.

The borders of cosmetic dentistry in the front aesthetic zone are very important. In the preparations of front teeth so that crowns are placed, it is important that the borders do not exceed the gum line or are slightly subgingival, so that the gums do not become inflamed. When the operations are performed deep within the gums, a vicious inflammatory cycle is caused, as the patient cannot remove the microbial dental plaque from the area it accumulates. Thus, when the tooth is drilled, it is required that an arrangement of all the gums (gingivoplasty) is performed around the tooth so that correct impressions can be taken.

9.What corrections can be made to the smile through prosthetics?

Prosthetics is the sector of dentistry that deals with prosthetic restorations such as crowns, veneers, bridges and the loading of implants.

In the front aesthetic zone, the correction of the color, shape and size of the teeth with the use of ceramic coverings, also called veneers, is also widely used. The veneers are “peels” of porcelain that are glued onto the outside surface of the teeth with resinous cements, require only a slight cut-off of dental tissue, but must be based on a substrate of 50% healthy enamel. If the conditions permit it, ultra thin veneers can be placed, without any drilling of the outside surface of the teeth.

In cases of great loss of dental tissue, edentulism, in complex cases, such as the one of bruxomaniacs, where the anti-aesthetic corrosions-facets in multiple tooth decay are observed, in cases of reduction of the vertical dimension-height of the face, the patients desire not only a functional restoration but also a good aesthetic result.

All ceramic crowns, bridges and dental implant prostheses fully restore the dentition and create, at the same time, a new aesthetic profile.

10. All ceramic or metal ceramic prosthetic restoration?

For many years metal ceramic restorations were performed in prosthetic operations with absolute success. The metal frame contributes positively to the resistance of the restoration, but has disadvantages regarding the aesthetics.

Between the porcelain and the metal frame an opaque layer is placed so that the metal is “blocked”. The final work has limited transparencies and iridescences in a very specific color range. The high requirements of patients, in combination with the incredibly rapid development of the technology and the biomaterials has led to the manufacture of all ceramic prostheses.

11.How are all ceramic prostheses manufactured?

For their manufacture, dental laboratories use the so-called cad-cam system which consists of three stages. The final impressions taken by the dentist and the imprints that occur, are scanned with a special scanner. Then, with the aid of a special software program, a 3D representation of the abutments and of the teeth is produced. Finally the mechanical component of the system manufactures, following the instructions of the PC, an initial composite and with the aid of special milling machines, the frame of the prosthesis is formed with absolute accuracy.

12. Which are the features of all ceramic prostheses?

All ceramic systems (zirconium, lithium disilicate, feldspar porcelain, e-maxempress) have an excellent stability, resistance, hardness and resistance to friction in a degree that is almost similar to the one of enamel. They are considered as the most biocompatible materials. In the last lab processing stage, the one of glazing, they are completely smoothened, which is quite important for the adjacent areas, both of the periodontium-gums and of the rest of the tissues of the mucosa. They are resistant to corrosion which is due to the temperature fluctuations and the acidic oral fluids, and there is no mention of allergic or toxic reactions. They have excellent visual properties and can excellently simulate dental tissues, through a variety of basic colors and additional coloring and modifiers.

13. Why should I replace my old amalgam fillings?

The high aesthetic expectations of the patients are not limited only to the front aesthetic zone, but most of them desire a perfect image in all the width of their smile. However, apart  from an aesthetic point of view, black fillings are not used anymore by the dentists for clinical reasons too. The amalgam is a mixture of metal elements which is not glued to the tooth; thus, over time, a minor penetration can be observed, which shall lead to the decay of the tooth and subsequently the necrosis of the pulp. In this case the root canal treatment-resection by a Special Endodontist has a 99% percentage of success in keeping the tooth within the oral cavity. The metal elements of the material are gradually subject to corrosion. Formerly, the dentists, in order to achieve the restraining shape of the tooth based on the principles of mechanics, proceeded to an excessive cut-off of dental tissues. This resulted to the weakening of the tooth over time, due to the great chewing forces that are applied every day, and to the development of cracks under the surface of the material that are forebodings of fractures.

14. What are the advantages of “White” fillings?

The incredibly rapid development of the technology of dentistry materials brought forth the “white” fillings made of composite resins. The materials, through special inactivating and adhesive agents, form bonds with the surface of the tooth. The cut-off of the dental tissue is minimal and is limited only in the cavity that has been formed by the decay. In the front zone they consist the materials of choice for the restoration of fractures. Modern materials have a wide range of colors so that they can seem identical to dental tissues, while having the ability to take the color of the surrounding tissues, like a chameleon, so that they can be fully harmonized with the underlying tissue. Formerly, there was a controversy regarding the resistance of these materials. Today, modern composite resins have excellent mechano-physical properties thanks to the ceramic granules they contain. High resistance to the powerful forces of chewing and to stresses, excellent aesthetic efficiency with transparent-opaque layers, capacity of opacifying and of natural fluorescence, radiopacity, excellent polishing and surface burnishing capacity.

15. Can implants be used in the front aesthetic zone?

If by the CT scan is decided that the bone meets the conditions and requirements so that an implant can be placed, implants shall consist the treatment of choice after the extraction of a front tooth. The success in the front zone depends on a high degree on the emergence profile of the implant, the way it emerges from the gums. In order to eliminate the use of the metal element of titanium, which can be colored gray by the mucosa, specialists have constructed implants with ceramic parts.

16. After the extraction, how can the gap be temporarily covered?

Modern clinical dentistry must guarantee to patients the “completeness” of their smile. It is a fact that a possible extraction, particularly in the front zone, may have an inhibitory effect for a patient’s visit to the dental clinic, as everyday life is ruled by constant social and professional obligations. The face aesthetics and the psychology of the patient are interrellated with edentulism, the partial or total loss of teeth. The solution that is usually applied is to place in the area of the extraction something artificial, laboratory-manufactured which, however, requires several working days to be constructed. The solution, thus, lies in the immobilization technique.  If one of the neighboring teeth is natural (the optimal result is achieved if both neighboring teeth are natural) or even if one of the neighboring surfaces is made of composite resin, it is possible that, with the aid of various modern inactivating and adhesive agents, the extracted tooth is glued to the neighboring ones, immediately after its extraction, after it is properly shaped so that it does not impede the healing of the tooth socket (alveolus) until the prosthetic restoration of the gap, either by the construction of a bridge, or by placing an implant.

17. What is the duration of the treatment?

Depending on the complexity of the case and the time the patient can spend, the treatment duration is defined. The duration varies from one day, in the case of dental cleaning, fillings, veneers to 1-2 weeks in the case of a prosthetic restoration. The duration can be increased when it is necessary that a periodontal treatment, gingivoplasty-gingivectomy or crown exposure takes place.

It is however important to remark that the duration of the treatment is not that important, although the time the patient can spend, due to social and professional obligations, is completely respected, and that the achievement of a final impeccable result is much more important.

18. Are the sessions painless?

All sessions are performed under local anesthesia and are completely painless. The anesthesia is quite safe for pregnant women as well as for heart patients although it contains epinephrine and it is wrongly believed that there may be side effects. The anesthesia in dentistry is local, without any effect to the central nervous system. The role of epinephrine is to achieve a level of anesthesia of a longer duration and a greater depth, which means painless dental work, as it causes a contraction of the smooth muscles, an increase of the peripheral resistances and of blood pressure, so that the local character of the anesthesia is maintained.

19. Will X-rays be needed?

A dental examination is quite incomplete without taking X-rays in parallel. In order to cause congenital anomalies, the overall radiation dose must exceed 5-10cG. In order to take periapical X-rays of a full dentition, 14 in total, with a protective lead apron, the dose does not exceed 0.00001cG. The dose is reduced even more with the use of modern digital equipment, high speed films, the long cone technique and the high power X-rays.

20. How long does the therapeutic result last?

The color of the prostheses does not change over the years, but the fillings may become opaque or absorb coloring substances in their edges depending on their microchemical structure and the abrasion that has been performed, which may require a rechecking and possibly a new abrasion. The result of tooth whitening and its duration depend largely on the daily habits of the patient (high coffee consumption, smoking) as well as on the genetic code of the teeth. Depending on the patient and the initial color of the tooth, repeat treatment sessions are recommended.

Regarding the preservation of the therapeutic result, the general habits of the patient also play a determining role, particularly various parafunctional habits (harmful habits of the oral and jaw system). It is worth remarking that bruxism (teeth grinding), is an extremely destructive habit which, due to the excessive forces that are applied, can cause even a fracture to the tooth or the prosthesis. It is important that the patient visits the dental clinic every semester for dental cleaning, in order to preserve the therapeutic result.

Constantinos Laghios, Dental Surgeon-Endodontist, M.S., Katia Georgaki Dental Surgeon