The aesthetic factor has now taken on a role of primary importance for the psycho-physical well-being of the individual. In a society where aesthetics and external beauty are the masters, a beautiful, harmonious smile is able to produce in the individual real well-being, especially psychic, which is to be sought at any cost. The aesthetics of the smile, or even better of the face, is a widely studied concept. We have always tried to impose canons to be strictly respected in order to be able to define a “beautiful” face. Not surprisingly, in the medical field, there is the so-called “golden rule”, a set of proportions, which, if respected, respond to concept of beautiful, harmonious and aesthetic. So a face that wants to be defined aesthetic, harmonious and pleasant, must respect the proportions of the “golden rule”. In a nutshell, it is necessary, imaginatively, to divide the face into different portions by means of horizontal and vertical lines in such a way that certain proportions are strictly respected. Horizontally, the face must be divided into approximately equal thirds: the lie of the hair attachment, the line of the eyebrows, the base of the nose and the tip of the chin.
Obviously, not respecting these proportions does not mean being “ugly”. Asymmetry is something to be expected and hoped for. In fact, many studies indicate that a certain imbalance I proportions makes the face more interesting. The asymmetry ca be corrected with make-up or hair styling.
Dental treatments also have their weight on the overall aesthetics of the face. In fact, the smile is the element that first catches the eye when we look a person in the face. Therefore, any problem affecting the anterior teeth affects the harmony of the smile and is immediately appreciated by the interlocutor. Aesthetic dentistry aims to correct or eliminate all those conditions that contribute to altering the smile and the harmony of the face in general. Dental treatments that can radically change the smile are represented by: veneers, Lumineers and teeth whitening. It goes without saying that any treatment that improves the aesthetics of the face is to be included in this dental branch.
- Veneers
The veneers, are artifacts designed to cover the vestibular surface of the anterior teeth. Then they cover the external, and therefore visible, face of the front teeth (from canine to canine). The aesthetic result is excellent and still represents the most predictable method for obtaining an optimal long-term result. They are made of ceramic or composite and are subsequently glued to the tooth with suitable cements.
Indications
Veneers have various indications in dentistry:
- Hypoplasia of the enamel, presence of dimples, grooves or spots
- Abrasions of the enamel, mostly on a mechanical basis (e.g. brushing)
- Amelogenesis imperfecta of a hormonal or tetracycline nature (this is an anomaly in which the enamel has formation defects that make it stained, often chalky and crumbly)
- Color changes from fluorosis (these are brown spots due to excessive intake of fluoride during childhood)
- Presence of aesthetically poor restorations
- Agenesis of the lateral incisor and its replacement by the canica
- Abnormalities of tooth volume
- Diastemas (presence of a space between the teeth)
- Alignment defects
- Repair of metal-ceramic crowns
- Coronal fractures
Contraindications
There are some contraindications to the use of veneers:
- Patients with inadequate oral hygiene
- Tooth with poor availability of enamel
- Serious crowding
- Discoloration from pulp necrosis or inadequate root canal therapy (if the tooth is devitalized it is better to resort to a complete crown in adults while in young subjects it is possible to do the veneer)
- Presence of parafunctions (for example bruxism or tooth grinding). In these cases, the success rate is reduced to 60%.
Materials
Veneers can be manufactured from ceramic or composite. There are substantial differences between the two types which consist of:
| Ceramic |
Composite |
| Expensive | Inexpensive |
| Fragile and not repairable | Repairable |
| Complex techniques | Simplified techniques |
| Optimal aesthetics | Optimal but time-dependent aesthetics |
| Greater wear of the antagonist | No antagonistic wear |
| Absolute biocompatibility | Biocompatibility linked to the quality of the finish |
| Physical properties stable over time | Time-dependent physical properties |
In summary, it is possible to say that ceramic is more aesthetic and more stable over time, in the sense that it retains its aesthetics even after years. However, it is more expensive and, if it gets damaged, it cannot be repaired but the artifact must be redone. Composite, on the other hand, is cheaper and in case of damage it can be repaired by adding composite. However, it is less aesthetic and wears out over time.
Operational phases
After explaining to the patient what the therapy consists of, it is possible to start the process that will lead to the final positioning of the veneers. The steps are as follows:
- Aesthetic waxing
- Mock-up
- Preparation
- Imprint
- Trial and cementation
The aesthetic wax-up is done to simulate the final result and is made starting from an alginate impression of the patient’s arches. It is then developed by the technician obtaining a plaster model to which wax is added in such a way as to simulate the final shape of the teeth.
The mock-up represents a real simulation on the patient’s tooth (even if the teeth are not touched). This is performed using composite shells made based on the aesthetic wax-up, which are tested on the patient’s teeth using a translucent gel. Thus, the patient will be able to realize the final result. If the patient likes it, the actual treatment can be done.
Tooth preparation is a technically complex step as only small amounts of dental tissue need to be removed ad is performed with burs.
The final impression is taken with high-precision and very fluid materials and must be precise in all details.
After the veneers are manufactured by the laboratory, they are first tested on the tooth with a gel of the same color as the cement that will be used for bonding. Special cements are used for cementation which differ according to the material of the veneer. If the veneer is in composite, the same composite used to manufacture it is used, while if it is in ceramic, specific cements are used.
- Lumineers
The lumineers, produced by the Cerinate company, whose ceramics have clinical studies at 20 years, are very thin all-ceramic veneers, as thick as contact lenses, which allow you to radically improve a smile in a completely painless way.
In fact, unlike traditional Lumineers, this method does not include any reduction of dental tissue in most cases and therefore no type of anesthesia.
A small cosmetic finish within the tooth enamel may be required in some cases. This method eliminated the need for anesthesia, retractor wire (the Lumineers are not positioned under the gumline) and provisionals; furthermore, there is no post-operative sensitivity, and the procedure is 100% reversible.
Lumineers give the possibility for a permanent solution to all those cases in which the individual is dissatisfied with his smile due to discoloration of the teeth or is dissatisfied with the shape of his teeth or has them not well aligned and does not want to encounter long and painful sessions at dentist and be subjected to uncomfortable anesthesia.
The most beautiful smiles are obtained when more teeth are treated: 8, 10 lumineers result in a much more aesthetic and attractive smile. With the method in just two sessions, the smile improves completely and painlessly, with permanent results over time and in an unexpectedly pleasant way.
The procedure includes a first visit in which the dentist takes the impressions of the patient’s arches and decides how to improve the appearance of the smile, analyzing the existing or desired shape and color.
The impressions are then sent to the United States, in Cerinate, where the veneers are manufactured.
Once arrived, the veneers are then tested, also to check the color of the cement to be used and, finally, cemented by means of an effective adhesive method.
- Dental whitening
Very often the teeth have a color that does not fully meet the patient’s expectations. In this case, teeth whitening is the ideal solution that can restore a pleasant smile in a short time without any pain.
Causes of pigmentation
The discoloration or pigmentation of teeth is very common and can depend on numerous different factors. They can be distinguished in extrinsic and intrinsic pigmentations (Fig. 1)
Fig.1 – An example of dental pigmentation
Extrinsic pigmentations
The extrinsic pigmentations are those located on the tooth surface, and which have a origin linked to external agents and can be easily eliminated by professional abrasion procedures performed by the hygienist (ultrasound, polishing with a high pressure bicarbonate jet). Here are some examples:
- Food and drinks: caused directly by the accumulation, over time, of phenolic compounds on the acquired film (protein film that begins to form immediately after cleaning the teeth). Practically, each color of the plant is given by the presence of one or more phenolic compounds (fruit, vegetables, tea, cocoa, coffee, cola, licorice, red wine, tomato, etc.)
They are metabolites of plants in which they perform many functions and include tannins. During the chewing of these plant foods, some of these chromogenic compounds are released in the saliva, they bind strongly to the proteins and, quickly, attach themselves to the protein film adhering to the tooth, causing a direct coloring on the surface or favoring and accelerating various reactions that lead to colored products.
Did you know that some fruit juices should be consumed in small quantities or with some precautions? In particular, some research has revealed that pineapple juice is particularly aggressive against the enamel, and therefore should be consumed moderately. Even meat cooked rare, artificial colors present in caramel desserts, syrups. There cause dietary discoloration due to the precipitation of the iron sulphide of the denatured proteins and of the iron present.
- Cigarette smoking: a separate discussion must be made for tobacco, commonly consumed in the industrialized West, through products such as cigars and cigarettes. Smoking, which has long been indicted as the number one enemy for health, is in fact also the enemy of the natural whiteness of the teeth, contributing over time to yellowing them. The advice in this is, predictably, always the same: stop immediately!
Among adults it is the most frequent case of tooth color anomalies. Saffron yellow colors caused by the deposition on the surface of the teeth of nicotine and partially unburnt products such as tar residues. In the case of heavy smokers, especially the front teeth turn gray and yellow even if good and regular daily oral hygiene practices are adopted. Tobacco corrodes the enamel.
The indiscriminate use of pure “whitening” natural products, as recommended by popular tradition, such as sage, baking soda, arctic lichen, lemon etc., should be avoided. A slice of lemon rubbed on the teeth eliminates superficial stains but, being acidic, causes serious damage to the enamel of the teeth which are eroded. There are, rather, whitening toothpastes, which can be used occasionally on the advice of the dentist, as they contain abrasive substances.
Intrinsic pigmentations
Intrinsic pigmentations are caused by the deposition of pigments within the tooth structure and which, therefore, can be removed with professional whitening methods. We may have factors that intervene before the eruption of the tooth and others that intervene after the eruption.
Pre-eruption factors: pigmentations caused by the deposit in the dental structure of pigments during the development and / or mineralization of dental germs. These pigmentations (which can affect both vital and non-vital teeth) require, for their elimination, more complex prophylaxis techniques and the use of products containing peroxides in turn catalyzed by specific professional equipment (such as lasers)
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- Tooth anatomy: the thickness of the enamel is an important factor. It is white and translucent, unlike the underlying dentin which is yellowish. A decrease in its thickness significantly changes the aesthetic appearance, making the tooth less white.
- Congenital causes: for example, imperfect amelogenesis or for teeth that are significantly filled and subjected to numerous conservative dentistry sessions, it may be necessary to use specific prosthetic techniques (ceramic veneers and / or crows, inlays) as whitening could produce its own pejorative aesthetic effects.
- Drugs: tetracyclines taken especially in the pre-eruptive period, which give the classic dark gray or brown color; the fluorine taken in excess determines an orange color; cyclosporins for local therapy in patients suffering from oral diseases of various kinds (lichen, aphthosis …); chlorhexidine (contained in mouthwashes).
Post-eruptive factors: they occur after tooth eruption:
- Dental trauma: sometimes pulp hemorrhage can occur with blood invasion inside the dentinal tubules. The blood, following the degradation of hemoglobin, produces ferrous compounds that pigment the tooth.
- Natural aging: by deposition of secondary and tertiary dentin or crystalline structures in the pulp, by thinning of the enamel, by decreased blood flow, by the accumulation of internal and external stains over time.
- Dental interventions: amalgam fillings for metal release, devitalization due to invasion of endodontic cement and gutta-percha molecules in the dentinal canals.
Types of whitening
There are two types of whitening: home and professional whitening. The whitening takes place by means of chemical substances called peroxides which through the enamel reach the area of union between enamel and dentin and here release oxidizing substances (these are oxygen radicals that bind to the pigments and neutralize them). There are two peroxides used for bleaching: hydrogen peroxide (formula H2O2, is the vulgar hydrogen peroxide) and carbamide peroxide (which during the type of whitening, some preconditions must be made:
- The “young” teeth whiten faster than the “old” ones due to a greater width of the dentinal tubules
- Whitening works most effectively in teeth where the discoloration has recently set in
- In general, the results and the time taken to obtain it vary from subject to subject
- Home whitening
It is performed by the patient without the intervention of the dentist. The characteristics are: low costs, lack of the presence of the dentist, low percentage of peroxide presence (from 6% to 10%), long time and less efficacy, non-individual application with universal masks. Examples are whitening strips and whitening gels with masks. However, they have no effect on devitalized teeth. Each manufacturer offers different types. Their effectiveness is modest and whitening of a maximum of one shade is obtained for about a year. Side effects are negligible and include: irritation of the mucous membranes in contact with the gel, tooth sensitivity especially in patients with many fillings. It may be recommended as a one-time maintenance method. There are also whitening toothpastes and chewing gum but the effectiveness is minimal or none.
- Professional whitening
It is carried out directly by the dentist: the characteristics are the following: high costs, the need for the presence of the dentist, high percentage of peroxide presence (up to 35%), reduced times (about half an hour), use of individual masks for maintenance (made from the patient’s impressions), guarantee of maximum success, duration of effect from 2 to 5 years. There are no contraindications. Side effects are minimal and can be limited to slight dental sensitivity which disappears within a few days. It is important to remember that the fillings and prosthetic crowns are not “bleached” so that, after bleaching, they will be of the same color as they had previously (Fig. 2)
Fig.2 – Before and after whitening
The whitening procedure involves placing a protective lacquer on the gum tissues adjacent to the teeth to protect them from the whitening gel. The gel is spread inside the individual masks and placed in the mouth. Then the lamp is positioned which accelerates the procedure for about 20 minutes (Fig. 3). After the first session it is possible to repeat the various steps for a second time if the result was not satisfactory. It is possible to obtain important whitening (up to 14 shades).
Fig.3 – whitening lamp
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