After pregnancy, the teeth are old and sore, and they are still soft, and the reasons found on the Internet are:
"The amount of calcium required by the body after pregnancy is large, and the growth and development of the fetus requires calcium, which may be absorbed from the mother, so the teeth are sour and soft" (big mistake!). ）。
Although the tooth composition is similar to bone, if the pregnant fetus does not get enough calcium, it can absorb the calcium needed from the mother's bone, but the teeth are not absorbed calcium.
In order to study whether the teeth during pregnancy will be absorbed calcium like bones, some scholars compared the mineral content of pregnant and non-pregnant women's teeth, and the analysis of chemical composition showed that the mineral content of the two groups of teeth was not different, that is to say, the teeth did not become soft during pregnancy. [1] There are other reasons why the teeth feel sore and soft, and hardcore science popularizes them for you.
01
Soft ribs on the structure of the tooth
Makes you sour to the point of tears
This circle of yellow in the teeth is "dentin", source: network
As shown in the figure above, the yellow part represents dentin and can respond to physiological and pathological stimuli. Structure covering dentin:
Located in the crown of the tooth is called "tooth enamel";
Located at the base of the tooth is called "tooth bone".
The dentin is filled with miniature tubular structures "from the inside out" that are closely connected to the pulp. Therefore, when dentin is exposed to the mouth and encounters external stimuli (such as cold air, bristle friction, sweet and sour food, etc.), it can produce a sensitive and sour feeling of the teeth.
图源：Inside Dental Assisting[2]
The yellow part of the picture on the right is the bone of the tooth, the source: istock photo, quizlet
As shown in the figure above, the enamel on the dentin surface of the crown part is thicker, and the bone on the dentin surface of the root part of the tooth is thinner. Among them, the bone near the edge of the gum is the thinnest, only 20-50 microns, which is about half the diameter of the hair.
The bone at the edge of the gum is about this thick, image source: dreamstime
The risk of dentin exposure near the edge of the gum is greatest because the dentin surface of this area is only covered by a thin layer of tissue, or even directly exposed.
02
Teeth are naturally afraid of acidity
Drop the "brick" at every turn
We often say "tooth demineration", where the "mine", scientific name "hydroxyapatite", is widely present in the bones and teeth of animals.
Hydroxyapatite, source: mindat
Our teeth have been used for decades, unless the teeth have "white spots", "black lines" and "moths", it is difficult to detect changes in the surface of the teeth. But in fact, the hydroxyapatite on the surface of the teeth has been in a "tug-of-war between attack and defense". Some acidic products, which can reduce the pH value in the mouth, are the "attacking side" in the tug-of-war.
If the attacker has the upper hand for a long time, the teeth will be deminated, just as a hard brick wall begins to disintegrate, and the bricks continue to fall out. When the wall collapses to reveal the dentin, we can intuitively feel the sensitivity of the teeth to hot and cold, sweet and sour stimuli.
When the attack and defense are easy, the teeth are reminalized, the hydroxyapatite can be re-deposited on the surface of the teeth, and the brick walls are refilled.
Image source: DMG
03
Afraid of acid, more afraid of acid "logistics support"
Human beings are developing too fast, evolving too slowly.
Although the teeth are naturally afraid of acidity, there is at least a heavy "remineralization" defense mechanism. But today's eating environment makes it easy for teeth to compromise with "acid", because the logistics of the attacking side are too strong.
Image source: Network
"Logistics support" is mainly carbohydrates (especially sucrose), which are the rations on which plaque depends for survival and can be metabolized by plaque to produce acid. When the diet is rich in carious foods (especially sucrose and refined carbohydrates), the output of acidic substances can be described as continuous.
With logistical support, bacteria (i.e., plaque) can use carbohydrates to produce acid, forming an effective "fire strike". When daily oral cleaning is not in place, plaque aggregation is more rampant, providing a guarantee for continuous "fire output".
While short-lived firepower strikes are not enough to produce demineration, bacteria in plaque can use carbohydrates (especially sucrose) and synthesize a "colloidal matrix" – a "long-lasting offensive" that facilitates the long-term adhesion of acidic products to the surface of the tooth. Frequent diets can also cause teeth to be repeatedly hit by acid. [3]
05
During pregnancy, the attacking force escalates
In addition to a series of changes in the body brought about by hormones during pregnancy, changes in lifestyle and eating habits will also have an impact on the "attack and defense tug-of-war" on the surface of the teeth.
Source: References [5]
On the one hand, the logistical support is stronger. The intake of carbohydrates during pregnancy tends to increase, providing more substrate for acid production, and due to physiological changes in pregnancy, frequent eating is required, the time between meals is greatly shortened, the buffering effect of saliva cannot be played in time, and the mouth will be in an acidic environment for a long time.
On the other hand, the offensive received "reinforcements". In addition to the use of carbohydrates by plaque to produce fire strikes, there are also firepower "stomach acid" during pregnancy.
In summary, the gum edge is the weakest in structure on the surface of the dentin, and it is most prone to demineration during pregnancy, making the teeth sensitive to hot and cold, sweet and sour.
Image source: Network
urgent! How to protect your teeth?
"For a while, it is not clear whether the teeth are sour and soft every day that affects the mood, or whether it is necessary to go to the teeth to affect the mood more." After explaining the above process to a pregnant mother during my online consultation, she replied.
So what do we do?
Remember 4 points: cut off logistics, reduce firepower, extinguish the offensive, and strengthen the body.
Cut off logistics: scientific sugar, drink less carbonated drinks, and stop eating after brushing your teeth before going to bed at night.
Reduce firepower: Develop good oral hygiene habits, brush your teeth daily and use floss or dental brush to clean your teeth.
Extinguish the offensive: Rinse your mouth after meals and stop eating carbohydrates between meals.
Physical fitness: use fluoride toothpaste, regular fluoride, fissure closure. [4]
Could it be more specific? How to choose toothpaste, how to choose snacks, can you guide me this big baby like you guide the little baby?
We can see the next popular science article.