How tooth decay develops and how cavities are prevented have been over complicated because it can be distilled down to a single sentence.
Sustain a net neutral pH over time.
The pH of the mouth at any given point in time, determines whether the tooth is demineralizing or remineralizing. Teeth are in a dynamic, not constant state.
- A low pH results in demineralization which is when cavities are progressing.
- A neutral pH results in remineralization which is when cavities are regressing or reversing.
However, cavities don’t develop in a single day because it is the net pH over a long period of time that determines its fate.
- If you have too many low pH days, you’ll probably end up with a cavity.
- If you have more high/neutral pH days than low ones, you’ll most likely not get one.
Yes, it is that simple but we’ll give you some more in depth examples to solidify your new found knowledge.
How to prevent cavities
The key to preventing a cavity is by sustaining a net neutral pH over an extended period of time. Put another way, do more pH raising activities while minimizing pH lowering activities.
- Increase frequency of activities that raise the pH back to neutral.
- Decrease frequency of activities that lower the pH to acidic levels.
We will now review common cavity prevention tips and how it ties in to the above framework.
|Cavity Prevention Activity||Raises pH||Prevents lowering pH|
|Minimize sugary foods||X|
|Brushing after meals||X|
|Use remineralizing toothpaste||X|
|Floss before bed||X|
|Minimize acidic foods||X|
|Chewing sugarless gum||X|
|Diet high in Ca and PO4||X|
Minimize sugar intake
Minimizing the amount of sugar foods that you eat will help reduce the chances of tooth decay. Mealtimes always leads to a decrease in oral pH due to digestive enzymes and the pH of the foods.
Oral bacteria feast on the sugars in your mouth and produce acid byproducts which further reduces the pH of the oral environment. It’s a double whammy.
Brush after every meal
You can negate the deleterious effects of mealtimes by brushing 30-60 mins after you eat. Doing so will help raise the pH of the mouth back up to neutral. That means you will spend less time in an acidic environment.
Use remineralization toothpaste
Brushing your teeth after meals is awesome but doing so with a remineralization toothpaste is even better. Toothpastes with fluoride or hydroxyapatite have an additional bonus of increased remineralization.
Those two ingredients will not only help raise the mouth pH but also initiate enamel repair. Yes, that means they can spearhead reversing tooth decay.
Floss before bed
The toothbrush can’t reach in between your teeth which flossing can. If you don’t floss, you will leave residual food that is in very close proximity to the enamel and that increases the chances of decay.
Rinse with mouthwash
Rinsing with a mouthwash is incredibly effective at neutralizing acids in the mouth. Studies have shown that even plain water can help raise the pH in the mouth.
The graph above shows the effect of various mouth rinsing solutions and their buffering effect on oral pH. Surprisingly, despite Listerine’s acidity, it does help negate acidity!
Minimize acidic foods
It’s not just sugary foods and carbohydrates that can initiate demineralization of the enamel. Any type of food that is in the acidic range will assist in decay formation. Oral bacteria thrive in an acidic environment but their activities are muted in a neutral pH.
Drink water throughout day
An often neglected but simple tip is to drink water throughout the day. Periodically sipping on H2O has a plethora of benefits.
- Washes away food debris and plaque.
- Fluoridated water will help resist cavity formation.
- Water also acts as a buffering agent to raise oral pH.
Chew sugarless gum
Chewing sugarless gum such as xylitol after meals can help prevent tooth decay.
- The gum’s stickiness can mechanically remove food from teeth.
- Chewing induces salivation which helps to buffer the mouth.
- Xylitol also has anti-cavity effects.
Diet sufficient in calcium and phosphate
Your teeth are made of a hard mineral called hydroxyapatite [Ca10(PO4)6(OH)2] which is essentially composed of calcium and phosphate.
These two minerals are crucial to having strong healthy teeth. If you don’t consume enough of them in your diet, your teeth will be more prone to decay and won’t be able to repair itself as readily.
- Dairy – milk, fortified plants milk, cheese, and yogurt
- Fortified juices
- Winter squash
- Canned sardines, salmon with bones
- Leafy greens (collards, mustards, turnip, kale, bok choy, spinach)
- Dairy – milk, yogurt, and cheese
- Legumes, nuts, and seeds
- Whole wheat breads and cereal
- Vegetables – asparagus, tomatoes, cauliflower
Demineralization & Remineralization mechanisms
Essentially, the pH in the mouth will dictate whether or not a cavity will ultimately form.
- When the pH drops to an acidic level, the bacteria become more active and enamel demineralization can occur.
- If the pH rises to a more neutral level, the bacteria become less active and enamel remineralization can occur.
In fact, when the oral environment dips below the critical pH of 5.5 that is when the enamel will effectively begin to demineralize. However, when the pH rises above that level, your tooth enamel can reverse course and begin remineralizing.
We will explain in greater detail how the mechanics of all of that works.
A cavity will form if the enamel demineralizes enough. As the name implies, demineralization is when the tooth enamel loses minerals.
How demineralization occurs:
- If the mouth pH drops below the critical pH level of 5.5 the enamel will demineralize.
- The process is characterized by the loss of the tooth minerals, phosphate and calcium.
- If enough minerals are lost, a cavity (hole) will form.
Cavities can be reversed through a process called remineralization, which is when minerals get added back into the enamel.
How remineralization occurs:
- If the mouth pH rises above the critical pH level of 5.5 the enamel will remineralize.
- The process is characterized by the re-incorporation of the tooth minerals, phosphate and calcium back into the enamel.
As miraculous as it sounds to be able to reverse tooth decay, there are limitations.
- The cavity must be contained within the enamel ONLY because if it has progressed to the dentin, it’ll be irreversible.
- You must have enough calcium and phosphate because if your diet is inadequate in them, your tooth won’t have the building blocks to repair the enamel.
The presence of fluoride or hydroxyapatite can help your tooth repair itself and reverse a cavity more readily. Both of these two substances are found in toothpastes.
- Inhibition of demineralization
- Enhancement of remineralization
- Inhibition of bacterial activity
Hydroxyapatite toothpaste benefits:
- Remineralizes teeth
- Plaque control
- Reduces teeth sensitivity
- Whitens teeth
The best way to prevent cavities is by sustaining a net neutral pH in the mouth over an extended period of time. Decay typically forms once the oral pH drops below the critical level of 5.5 but it can reverse course if the pH rises above that.
Yes, there are a lot of “tips” on how to not get a cavity but if you think about it from a higher level, they all function based on affecting the pH. Therefore, all you need to remember is that tooth decay formation and prevention has to do with chemistry.