Flexural Strength
What Is Flexural Strength? (Why Your Crown Won't Snap Like a Potato Chip)
Flexural strength is the technical term for how much bending force a material can take before it breaks. Think of it like this: if you tried to snap a potato chip, it would break instantly (low flexural strength). If you tried to bend a rubber spatula, it would flex without breaking (high flexural strength).
Here's why this matters for your mouth: every time you chew, your crown experiences bending forces. That innocent bite of crusty bread is trying to flex your crown. The higher the flexural strength of your crown's material, the more abuse it can take without cracking, chipping, or failing when you're just trying to enjoy dinner.
The Numbers Game: A Human-Friendly Guide
Flexural strength is measured in Megapascals (MPa). While the numbers are technical, the comparison is simple:
- Old Porcelain Crowns: 100-150 MPa (pretty, but fragile)
- Natural Tooth Enamel: 300-400 MPa (nature's benchmark)
- E-max® (Lithium Disilicate): 400-500 MPa (even stronger than your natural tooth!)
- Zirconia: 900-1,200+ MPa (the undisputed heavyweight champion)
A material with a high flexural strength gives us, and you, the confidence that it can withstand the powerful forces of daily life, and even the extreme forces of nighttime grinding.
How Flexural Strength Influences Your Crown Choice
Understanding this property allows us to select the perfect material for your specific needs.
- For Front Teeth: We need a beautiful material that is also strong enough for daily function. This is where E-max® shines, offering elite aesthetics with a flexural strength that is more than enough to handle anything except using your teeth as tools.
- For Back Teeth: The priority here is pure strength. The chewing forces on your molars are immense. This is where Zirconia is the clear winner, with a flexural strength that is virtually indestructible in the mouth.
- For Grinders: If you clench or grind your teeth, you need a crown with the highest possible flexural strength. Zirconia is the only material we recommend for the back teeth of a known heavy grinder.
The Hidden Benefit: Preserving Your Natural Tooth
One of the best advantages of high flexural strength materials is that they can be made much thinner without sacrificing durability. A thinner crown means we have to remove less of your healthy, natural tooth structure during the crown preparation. This is always our goal—to preserve as much of your own tooth as possible while providing a restoration that is built to last.
Ultimately, flexural strength is the unsung hero of your crown's longevity. While you'll never see it, you'll definitely feel its absence if a crown fails.
Here's what we want you to remember:
Flexural strength is a direct measure of a crown material's durability and resistance to breaking under pressure. Modern materials like E-max® and Zirconia have revolutionized dentistry by offering incredible strength that far surpasses older porcelains.
Every patient's situation is unique.
Choosing the right material is a balancing act. For a front tooth, we may choose the beautiful resilience of E-max®. For a back molar in a patient who grinds, we will always recommend the superior flexural strength of Zirconia. We match the material to the job it needs to do.
Tired of breaking crowns or worried about your options?
Want to understand which materials can truly handle your bite? We're here to give you honest, personalized answers. Schedule a consultation at our Woodland Hills practice – let's talk about what's really best for your smile.