Episode 26.
Why do people lose teeth?

Question:

Key Points:

• Primary Teeth (i.e. baby teeth) are lost in order to make room for adult teeth
• One reason we have baby teeth is likely because our jaws grow from the time we are born until we are adults. So, baby teeth are smaller in order to fit our smaller mouth
• Baby teeth are sharper in order to make it easier for them to push their way through the gums
• When adult teeth are coming in properly, the baby teeth roots disolve and the adult tooth takes the place of the root and grows up through the gums; this makes it easier for the adult teeth to come in.
• When baby teeth stay too long, it is called over-retaining.
• It could be that adult teeth are misaligned, or for some reason (we don't know why yet) the baby teeth might not disolve at the same time the adult tooth is trying to come in
• When do baby teeth come in:
  • Bottom front two teeth (central incisers) in 6-10 month olds
  • Top front two teeth come in the 8-12 month old range
  • The the top second teeth (lateral incisers) come in at around the 9-13 month timeframe
  • The bottom second teeth come in the 10-16 month timeframe
  • Canines come in at the 16-23 month timeframe
  • All four of the first molars come in between 13 and 19 months
  • The second molars come in at the 23-33 months timeframe
  • All the baby teeth are in by the age of 3
• When do adult teeth come in:
  • The front 4 teeth (one in each quardant) are lost in the 6-7 year old range
  • The next tooth in each quadrant is in the 7-8 year old range
  • The canines are usually lost in the 9-12 year old range
  • The first molars are usually lost between 9 and 11 years old
  • The fifth tooth (second molar) comes out in the 10-12 year old range
  • The 6th tooth (third molar) doesn't have a baby version, but comes in when you are around 5-8
  • The sevent molar comes in at around 12 years old
  • The last teeth, i.e. wisdom teeth, come in around the age of 18
• When your wisdom teeth are just starting to come in, go to your dentist then and see if there is going to be room in your mouth. If you need to get them pulled, it's better to get them pulled sooner rather than later
• The #1 reason for losing adult teeth is gum disease
• When there is too much bacteria living in the plaque in your teeth that it irritates your gums, it is called gingivitis
• If this infencts your actual gums, then it is called pariodontitis (i.e. periodontal disease)
• There are other reasons people can lose their teeth: cavities, loss of bone mass, etc
• The best kind of science experiments are controlled and double-blind (and randomized, though I didn't mention that on the podcast)
• Controlled means that there is a "control group" where there is no treatment at all, just do nothing
• A double-blind experiment means no one, not the researcher or the patient, know whether a person is in the treatment group or the control group