Zirconia Crown

Treatment options for the restoration of baby teeth are increasing. Over the past few years zirconia, dental crowns for children have become more and more popular. Parents prefer Zirconia crowns over stainless steel crowns because they are more natural-looking and aesthetically pleasing. 

 Dental crowns are placed over decayed or developmentally defective teeth. It can be used to restore decayed primary teeth. Zirconia crowns are particularly gaining favor for the aesthetic restoration of front and back baby teeth.

 In the last two decades, Zirconia has found numerous applications in adult dentistry including prosthetic crowns, dental bridges, endodontic posts, and implant abutments. There is still not a lot of clinical data available about Zirconia ceramic crowns for baby teeth, however, Zirconia crowns in adults are very durable and retentive according to Brisbane Dentist Pure Dentistry. 

 With dentistry for adults, an acceptable restoration is achieved when both the shape and the function of the tooth are restored. However, with dentistry for children with primary teeth, the shape and aesthetics of the restoration are typically secondary and the primary consideration is given to the functional requirements but this trend is changing.

Zirconia is a bioceramic material and it has been available to paediatric dentists as a restoration material since 2010. It is used to make prefabricated biocompatible dental crowns in various sizes and shades for application in both front primary teeth and the back primary teeth. They are very durable and aesthetic and its wear is in the order of the natural tooth enamel. Refer Dental Crowns in Brisbane by Brisbane City Dentist for more info. 

 Aesthetic restoration of severely decayed primary teeth is a great challenge in paediatric dentistry. Zirconia crowns can be used as an aesthetic restoration solution for primary teeth in children. It can be used to restore primary molars with:

• Kids Who have severe dental caries 
• Multi-surface caries
• Pupal therapy

 With Zirconia crowns, paediatric dentists no longer have to forego aesthetic considerations when a full-coverage restoration is necessary. Restoration using white Zirconia crown is an option for restoration of primary teeth when they are:

• Chipped
• Damaged
• Broken
• Not developing properly
• Extensive decays where restoration has the risk of breaking

The popularity of white Zirconia crowns is because of their natural color. They also have a highly finished polish which reduces plaque accumulation. These crowns help with the preservation of gum health because the cervical margin is a knife-edge.  Tooth restoration using white zirconia crowns is more acceptable by patients (compared to stainless steel restorations).

 Preserving baby teeth is essential in the development of children. It’s not “just a baby tooth”! Baby teeth assist with adult teeth erupting in the right direction. Baby teeth affect:

• Speech
• Nutrition and growth
• Overall health

Dental crowns for babies may be required when there are large cavities in the mouth. Crown protects teeth and can prevent repetitive dental procedures on that damaged tooth. Crowns may be recommended when a baby tooth is broken or when the tooth has not been developed properly.

For adults, refer dental crowns in Brisbane by Pure Dentistry.

Early childhood caries is relatively common among children. In the past, extensively decayed primary teeth have been extracted and restoration was not a common option for many children. With the advent of modern dentistry and dental treatment under general anaesthesia, the treatment of choice has shifted from tooth extraction to tooth restoration. Because, when suitable, restorative dentistry can recover both the function and also the aesthetics of the decayed tooth.

Pre-milled Zirconia crowns now offer an aesthetic alternative to stainless steel crowns. Stainless steel crowns and Zirconia crowns are both available for children. Stainless steel crowns are the earliest widely used tooth restoration technique in children. It has been and is still being used successfully to restore dental decays in children. Over the past decades, SS crowns, though deemed unattractive sometimes, have served countless children as functional restoration of primary teeth. Because silver crowns offer a utilitarian type of restoration, not an aesthetic one.

 Stainless steel crowns are also called silver crowns because they are silver in color. It is made of Chromium (Cr), Nickel (Ni), and Iron (Fe). SS crowns are commonly used where aesthetics are not concern such as the back molars.

 While stainless steel crowns are quite practical, durable, and economical solutions, due to their unaesthetic look, their application is limited to back teeth and not the front teeth. For the restoration of the front teeth, there is a high demand for more aesthetic solutions.

 Paediatric dentistry guidelines recommend the use of stainless steel crowns when there are severe decays on at least two surfaces of the tooth. This is an effective treatment however it is often and frequently refused by parents. When parents have opposition to the appearance of a silver crown, paediatric Zirconia crown can be an alternative.

 Zirconia crowns are normally thicker than SS crowns (silver crowns). When compared to stainless steel crowns, Zirconia crowns are more expensive and also require more tooth reduction. Unlike stainless steel crowns, Zirconia crowns cannot be crimped and its retention relies on the internal surface design and the cementation of the crown.

Metal teeth are not aesthetically pleasing. Nickel is used in stainless steel crowns as a hardening agent. Some patients are allergic to nickel and it can trigger metal allergies in some children. Nickel may also produce toxic side effects such as localised irritation of the tissues.

Because Zirconia crowns cannot be crimped like silver crowns, the kid’s dentist must prepare the tooth for the Zirconia crown to fit. This means that extended preparation and fitting time is necessary which can affect the cost of the dental treatment specially if the dental procedure is being done under general anaesthesia. Refer dental treatment for children under GA in Brisbane by kids-dentist.com.au.

Indication for use of white Zirconia crown for kids include:

• Fractured teeth
• Teeth with hypoplastic defects
• Teeth with a large carious lesion
• Aesthetic restoration of tooth defects
• After pulp therapy of a tooth
• Extensive tooth loss due to attrition
• Extensive tooth loss due to bruxism
• Extensive tooth loss due to Abrasion
• Allergy to nickel and contradicted for silver crowns 
• Minimum 2mm of supragingival health tooth structure
• Crown discolored or fractured due to traumatic injury
• Teeth with multi-surface carious lesions with or without pulp therapy

Teeth with developmental anomalies (dentinogenesis or amelogenesis imperfecta)

The contradictions for use of Zirconia crowns in kids include:

• When the child is uncooperative
• When not affordable
• Subgingival soft caries
• In a crowded arch (crowded dentition)

When a space maintainer or an orthodontic appliance requires soldering to be done on the crown

The selection of the Zirconia crown involves a bit of trial and error. More tooth preparation is required if the Zirconia crown does not seat completely on the tooth. The crown cannot be adjusted without additional tooth preparation. The dentist may change the size to a smaller crown if the crown fits loosely. Further tooth reduction is required if the crown does not fit completely because forcing the crown onto the preparation may damage the crown. With Zirconia crowns there is no contouring, crimping, or trimming. They are not flexible and force will result in a fracture.

Just as in cosmetic dentistry for adults, the demand for cosmetic services and aesthetic restoration of damaged teeth in children is progressively increasing each year. This demand is answered by manufacturers of Zirconia paediatric crowns.

These crowns are made by Zirkonzahn. 6 sizes are available for back teeth and 4 sizes are available for front teeth. Canine crowns are not available from this company. Signature Crowns have an overall thickness of 0.5 mm and a 0.2 mm feather edge margin. It is quite thin (0.5mm) and therefore with these crowns, less preparation is required.

 The benefits of Signature Crowns according to the manufacturer are:

• Less inventory
• No space loss crowns
• Best shade match
• 1400+ MPa Strength
• Micro-mechanical interlocking
• More cost-effective

NuSmile is a manufacturer of children’s crowns. NuSmile crowns are fabricated using digital scans of natural primary teeth. They are designed for full coverage restoration of decayed or damaged baby teeth. The dentist can determine the size of the crown using Try-In Crowns before preparing the tooth. 

 NeuSmile crowns may require approximately 20% more reduction of the tooth compared to a standard stainless crown. 

 Paedo shades: light and extra light

Margin: 0.2 mm

The fitting can be checked before final cementation using Nusmile Try-in Crown. Try-In saves the dentist’s chairside time and also eliminates extra steps and disinfection of crown and also improves bonding of Zirconia to luting cement. 

Kinder Krowns have internal retention threads that provide mechanical retention and allow the paediatric dentist to use glass ionomer cement and the actual crown for intraoral try-ins. They can provide a natural-looking smile by glazing and polishing Zirconia Kinder Krowns.

EZ Pedo Crowns by Sprig Oral health Technologies fabricates dental crowns for all 20 baby teeth globally.  Side by side placement of Zirconia is easier using EZ Pedo Crowns thanks to their flat-fit interproximal contours. These crowns have retentive grooves that extend to the crown margin which provides more bonding surface area and prevents cement washout and entry of bacteria.

Cheng crowns are designed and fabricated to enhance aesthetics and simulate natural teeth. They can reduce plaque build-up at the margins. With Cheng Crowns Better retention is achieved by the simulated crimp. It has a crimped margin of 0.2mm which offers a natural emergence profile while preserving ease of crown fitting.

Kids-e-crown has high biocompatibility and is gentle with the gums, according to the manufacturer. It can be used in aesthetic applications and has acceptable strength for daily use. The inner surface of the crown is provided with micro-perforation which provides a high strength adhesion with regular GIC cement. It creates a strong bond with the tooth until the primary tooth is shed and is replaced with the permanent tooth.

The treatment of choice for a carious front baby tooth which is close to the dental age of exfoliation is usually extraction. Refer to tooth extraction for children in Brisbane. But with a child who has a long time until exfoliation of a baby tooth and eruption of the permanent adult tooth, extraction could cause speech and chewing problems and may not be the best treatment option because of an unaesthetic primary front tooth can cause negative self-perception in the child.