How Long Do Dental Crowns Last?
Dental crowns are placed to protect the tooth structure, to maintain the arch integrity and harmonious occlusion.
A crown is placed on a tooth that requires support in cases of bulkier restorations, cariously destructed tooth crowns, root canal treated teeth etc.
Basically, dental crown holds the remaining tooth structure strongly so that it can function properly, therefore crowns increase the life of the remaining part of the tooth.
How long do dental crown last?
The life span of the crown is determined by the following important factors:
- The type of material used in crown preparation.
- Site of crown placement.
- Masticatory load or the chewing stress at the site of crown in the mouth.
- Eating habits and patterns.
- Arch shape: sharper arches like V shaped creates more stresses as compared to U shaped arches.
- Alignment of teeth: in crowded or malaligned teeth, stresses are concentrated indifferently. Aligned teeth has more uniform stress distribution favoring increased lifespan of the crown.
- Para-functional habits like bruxism, night grinding reduce the lifespan as continuous heavy forces are delivered even at rest.
- Oral health and hygiene.
Lifespan of crown
The factors mentioned earlier collectively affect the durability and lifespan of dental crowns.
Depending upon the material used for its fabrication:
On an average, metal crowns lasts longer as compared to other types of crowns. Metal crowns lasts for around 20 to 25 years or even more in few cases. Porcelain and ceramic crowns lasts for approximately 5 to 15 years.
Full coverage metal crowns lasts longer because metal has excellent strength, abrasion resistance and are tougher even in thinner sections. The ceramics and porcelain requires more bulk to attain the strength comparable to metals.
PFM crowns (porcelain fused to metals) also lasts for around 5-10 years or to 15 years in few cases.
Depending upon the coverage of crown:
Full coverage crowns (covering all the surfaces) lasts longer as compared to partial crowns (3/4 and 1/2 crowns). The sequence in descending order from longer to shorter lifespan:
full coverage crowns > seven-eighth crowns > three-forth crowns > one-half crowns
Dental crowns on front and back teeth:
The crowns in the front teeth lasts longer as compared to that of the rear or back teeth. The major reason being is the chewing forces.
These forces are extremely high in the rear teeth region (120- 180 lbs). Front teeth are used only for biting purpose. So, dental crowns in the front teeth lasts longer.
How can I make my crown to last longer?
Crowns can be made to last longer by choosing the proper type of crown, appropriate material, proper tooth preparation and technique of crown placement. But these factors are determined by the dentists.
However once the crown is placed, there are a number of things you can do to make your crown last longer. Small efforts but effective habits like:
- Correct brushing technique.
- Brushing twice daily.
- Regular use of dental floss and mouth rinses.
- Good eating habits.
- Avoiding hard food chewing.
- Inculcating healthy habits, quitting smoking.
- Maintaining good general health: this maintains the gums and bone health ultimately improving the fit of the crown with increased lifespan.
- Regular dental visits.
- Water jets can be used to flush the area specially near the margins of the crown. This lowers the plaque retention and washes off the toxins and bacterial products.
Frequenlty asked questions
Can a crown last a lifetime?
Ideally, it should last a lifetime. But, practically the oral tissues undergo many chances anatomically and physiologically thus altering its shape, form and function.
A crown may last if it is placed at an older age without any systemic problems or systemic history. But it can be least expected to serve a lifetime purpose if placed at an early age when the body and the tissues are susceptible to many changes at biological, physiological, anatomical and hormonal levels.
How much does it cost to replace a dental crown?
Replacement of the crown cost you between $700 to $2000 depending upon the type of crown.
Replacement requires reshaping the tooth to obtain a new dental crown. So basically you need to pay for a new crown.
Can X- ray show decay under a crown?
Initial caries shows no radiolucency even in normal teeth. As more mineralized structure is destructed, the more it can be distinguished in radiographs.
But under a dental crowns or in secondary caries, it actually becomes difficult to rule out completely as the radiolucency is masked by the radio-opacity of the crown.
In cases of cervical (neck) caries, it can be ruled out with X- rays and in root caries, it is easily distinguishable. X-rays does not show decay beneath the crown. To rule out such caries, it requires crown removal and then X- rays can be taken.
How long do crown last after root canal treatment?
Crowns usually last for 10 to 15 years. They may last longer if properly taken care of.
Root canal treated tooth are more fragile as compared to vital tooth as the crown structure is lesser and also the water content is less due to the absence of pulp.
So, to improve the life span of the crown on root canal treated tooth , it is better to avoid chewing hard food like nuts and sticky food.
How does a dentist remove a crown to replace it?
Removal of temporary crowns can be easily done with the help of straight elevator. It is easier because the cement used to glue does not bind strongly.
Permanent crowns require more force as stronger adhesives are used. Specialized crown removal kits are available which have an instrument to dislodge the crown from the tooth.
What should I do if a crown is very old?
If you have any discomfort, pain then you may need to change it. But if it is clinically well functioning with no problems, then there is no need to replace it.