A Comparison of Zirconia, Emax and Ceramic Hybrid dental crowns
The world of dentistry and dental materials is vast and ever expanding. Research and technology has enabled dentists and dental technicians to provide the best medical options as well as cosmetic alternatives that help patients to restore their functionality without compromising on appearance. Earlier, getting a dental treatment done entailed either extraction of a tooth or replacing a tooth with no cosmetically pleasing options such as metal crowns that looked jarring and out of place.
Gone are the days when these were the only two options. Extraction is one of the last methods used by dentists as most dentists believe in preserving the teeth and the roots of a tooth in the patient's mouth and for good reason - extraction often leads to many other problems both dentally and in other parts of the body especially in the case of patients who are aged, or with co-morbidities.
Using a metal crown, however convenient and cost efficient it is, is not the greatest option out there. Those who needed anterior restorations had no real esthetically pleasing options which caused challenges to patients. Even with posterior restorations, metal crowns had their own reservations and drawbacks such as being too large and requiring to remove a large portion of the original teeth, the jarring metal colour and the unsuitability to those who had metal allergies.
Keeping in mind these challenges, researchers have been forever working towards better and more convenient options for patients and after many a decades options such as Zirconia crowns, Lithium Disilicate crowns such as Emax and Hybrid Ceramic crowns with ceramic veneer and the core strength of composite has been invented and been in use for many years now. These options have been revered by dentists and patients alike as it presents new opportunities for both parties and provides choice based on their unique requirements. Unlike its predecessors such as Metal Crowns, Porcelain fused to metal crowns, All ceramic or Composite Resin crowns, these new age crowns are lab made with CAD/CAM Technology and offer great many benefits to patients and dentists alike not only with appearance but with reduced chair side time, preparation time, strength, durability, biocompatibility etc.
Before dwelling into crowns, it is important to note that both dental crowns and bridges are made with these materials. Even though some crowns are great when used as single teeth restorations, they may not work out as well when used as Dental Bridges. Just like everything else Zirconia dental crowns, Emax and Hybrid Ceramic Crowns all have their own advantages and disadvantages and patients can choose one over the other based on their requirement and the level of pros over cons.
Zirconia Dental Crowns
Zirconia Ceramic Crowns are one of the most popular types of restorations today. They are a type of ceramic crown restoration but have a significant difference when it comes to their material. The Zirconia crown tooths are made of Zirconium slabs that are stabilised using Yttrium. This element is known to be extremely stable and biocompatible in the body. Their superior strength and durability has made them one of the best dental restoration materials.
Zirconia crown price differs from one place to another. Some brands may charge higher or lower when it comes to the cost of Zirconia crown but they usually range between a few hundred dollars on average. Zirconia crown cost also depends upon the customisation that patients may opt for now. One of the biggest flaws for Zirconia crowns if one had to point out was the fact that they had an opaque white colour when moulded into crowns which was not very natural. Today it is possible to colour match Zirconia crowns to the natural enamel of a patient by using various techniques that create natural stains on the teeth.
Zirconia dental crowns are highly recommended by most dentists today worldwide mostly because of its qualities that are unmatched such as:
- The strength that is unlike any other dental material
- Durability which is on par with the strength
- Easy chair side restoration and adjustment time
- Highly precise design using CAD/CAM Technology
- Cuts down on the restoration preparation time
- Access to natural teeth like customisation
- Excellent biocompatibility for patients
- Best choice for patients who have metal related allergies
Lithium Disilicate Crowns
Lithium Disilicate Crowns are one of the new varieties of dental crowns that are available in the market. Lithium disilicate crowns are popular by their brand names such as IPS EMax or Lisi which are the two different kinds of brands with their Lithium disilicate crowns. IPS Emax is the most popular option that is used by dentists all over the world. The Emax variety of crowns are made with Lithium Dioxide, Quartz, Phosphorus Oxide, Alumina and Potassium Oxide. This is a strong and durable type of ceramic crown because of its low thermal expansion factor which benefits patients especially who have sensitive teeth. The material can be made into a thin veneer but still is able to deliver performance of upto 400 megapascals of biting force tolerance.
Emax can be used not just to make crowns but can also be used to make Onlays, Inlays, Bridges and veneers. One of the best advantages of using Emax when compared to other crowns was the esthetic benefits. In situations where Zirconia crowns can be too white or PFM and other ceramic crowns can look grey, Emax can look very natural thanks to its fluorescence and bright teeth like nature. The crown can also be stained to match the exact enamel shade of the patient and with EMax, it is hard to tell whether the patient has a crown or not. The natural translucent enamel like feature is one of the best advantages of Emax crowns.
Other advantages of Emax are its durability and biocompatible nature which is a good option for patients with metal allergies. On the con side, the material is also not as strong as Zirconia and the restoration times may be higher. Emax crowns are developed on a customised basis and therefore chairside adjustment time could also be higher. The price for Emax crowns are also slightly expensive and therefore may not be the first preference for cost conscious patients. They are an ideal option for patients who are looking for anterior restorations where esthetics are of paramount importance.
Hybrid Ceramic Crowns
Hybrid Ceramic crowns are a new kind of breed that has shown up at the dental scenario in the last decade or so. Hybrid Ceramic crowns try to blend the esthetics of ceramic crowns with the strength and durability of composite crowns. Dentists and even patients agree on the fact that Ceramic crowns, however esthetic and pleasing they may be, are only limited to anterior restoration and are susceptible to chipping and breakage. They have lower strength and durability when compared to other materials such as PFM crowns, composite resin crowns etc. But the problem with the other crowns was the lack of esthetics in them which limited their usage only to posterior restorations or in some cases as temporary crowns.
Hybrid Ceramic crowns are a perfect blend of the two worlds - this dual network structure crown offers the strength and durability of Composite crowns while the esthetics of the ceramic outer structure. The polymer network structure of Composite laid within provides good resilience and bite force and can withstand the functionalities of posterior based crowns. The ceramic overlay and network structure within when combined with the polymer based network works well to reinforce this and provides one of the best products in the market. The advantages of Hybrid Ceramic Crowns are:
- High Fracture Resistance and Load Capacity
- Crack prevention and does not chip
- Better elasticity and module level
- Less brittle than traditional ceramic crowns
- Less abrasive when compared to traditional composite crowns
- Resistant to the natural compressive force of jaw
- Designed using high tech CAD/CAM facility
- Reduces chair side time with high precision and thinner walls
- Can be used for Inlays, Onlays, Veneers, Bridges etc
- Reduces chairtime, restoration time, prep time
- Natural shade can be achieved with staining
- Translucency and enamel shading makes it customisable
These are some of the advantages of Hybrid Ceramic Crowns. It is to be noted that this material and crown type is still being studied and researched and there is limited knowledge and results in the market. However promising, there is still limited access and limited research in the area. The costs may also be higher and variable from one place to another due to its brand new status.
In conclusion, it can be noted that all 3 kinds of crowns have their own benefits and advantages over each other. There are some negatives with each kind of crown and there are more and more dental restoration materials and new technologies that are added each day. This makes the market always fluctuating and dynamic. What is superior today may be outdated and replaced tomorrow. Given the pros and cons of the 3 popular ceramic based crowns, it is to be concluded that the preference and choice resides with the patient and the dental practitioner.
Zirconia crowns are a proven product in the market but Emax and Hybrid crowns are also fast moving and catching up with the latest trend. As and when technology updates and new methods are added, research can help strengthen the pros and cons of each kind of crown and help patients decide on which dental material and crown is most suitable for them and their particular requirements.