Esthetics and durability are the name of the game when it comes to dental crowns. While there are multiple variations within the types of available materials, they can be grouped into metal, ceramic, or acrylic. Metal crowns for adults are typically noble alloys (containing a certain percentage of precious metal). Ceramic crowns can be layered, involving different levels of ceramics with different shades to create an exact replica of the tooth's natural structure and translucence; they can also be monolithic, made from a single block of ceramic. And then there are acrylic dental crowns. These are the least expensive option, and while they can generally meet a patient's esthetic needs, what about their durability?

Acrylic Materials

Acrylic crowns (also called all-resin crowns, or composite resin crowns) are not always a suitable option, and your dentist may not necessarily suggest them. This is particularly relevant for molars, which are subjected to intensive biomechanical (chewing) forces. This ongoing force can cause an acrylic crown to fracture, making them unsuitable for molars.

Porosity

Although acrylics can serve a valuable purpose as dental restorations, they're the most porous option. Annoyingly, this makes them vulnerable to discoloration. There can be no shirking when it comes to your oral hygiene. In fact, it's wise to get into the habit of thoroughly rinsing out your mouth after eating or drinking anything that's known to stain teeth. 

Preparing the Tooth

You must also consider the preparation work a tooth needs before a crown can be fitted. A small amount of the tooth's structure is removed so that the height and circumference of the tooth remain the same after its restoration has been added. Acrylic crowns require the most tooth structure to be removed because the material isn't as strong as metal or ceramic, so the acrylic restoration must be thicker to compensate for this. 

Dealing With Breakages

An acrylic crown's relative lack of strength makes it more prone to breakage. Small, superficial cracks can often be repaired without removing the crown (your dentist simply patches the damage using a color-matched composite resin). More intensive damage means the crown must be replaced, and due to the amount of the tooth's structure that has been removed, the tooth permanently needs a crown. If a replacement is needed, it can still be acrylic, or you may decide to have a metal or ceramic substitute.

There are some drawbacks to acrylic crowns, but in terms of your budget, they may be the best choice. Provided you're willing to take care of your acrylic restoration, it can provide years of service, but some maintenance may be needed, and it's unlikely to last quite as long as a metal or ceramic crown.