Archives for March 2013

4-F: Unfit for Service because of your Teeth?

Rejected Due to lack of four front teeth 4-F or 4FMany civilians as well as military personnel are familiar with the term 4-F (also called 4F).  4-F is a classification given to a new U.S. military registrant indicating that he or she is “not acceptable for service in the Armed Forces” due to medical, dental, or other reasons.

Most people do not know that the term 4-F (or 4F) originated in the Civil War and was used to disqualify army recruits who did not have four front teeth with which to tear open gunpowder packages.

History of the term 4F or 4-F

The term 4F or 4-F started in the Civil War.  As both Confederate and Union soldiers were being recruited, there were very few medical or dental reasons for rejection.  Quite simply, the battery of tests and screening tools available today simply did not exist back then.

Photo of Union Soldiers in Civil War and they each had their four front teeth and were not 4F nor 4-F

Photograph of Union Soldiers in the Civil War. On enlisting, they were not classified as 4-F since they had at least four front teeth. Source unknown.

It was noted, however, that in order to properly load a rifle quickly, the gun powder cartridge needed to be ripped open with the teeth. Molars and premolars in the back of the mouth were not sufficient for this task. Only the incisors and canine teeth in the front could be utilized.

Photo of Civil War Dentist evaluating a soldiers teeth to see if he is 4F or 4-F

Civil War Dentist examines a soldier’s teeth. Courtesy Association of Army Dentistry, San Antonio, TX.

Back then, routine dental care did not exist, and many people in their late teens and 20s were missing several teeth. If a recruit could not open the gun powder cartridge with his teeth, he would not be able to reload quickly, placing himself and his fellow soldiers at greater risk.

So, while evaluating new registrants, a dental exam was performed to see if each young man had at least four front teeth. The dentist would examine the young man and evaluate the front teeth (or lack thereof). Those young men without four front teeth were disqualified and not permitted to enlist.

Naturally, a “code” was needed to designate why the registrant was unfit for service. So someone (presumably a Union Officer) came up with:

4-F (lacks 4 Front Teeth)

And from that point forward, the term 4-F was used in this manner.

Use of 4-F in the Military Today

Photo of four front teeth 4F or 4-F and this patient could serve in Army in Civil War

Front teeth of a military patient of mine. He could have served in the Civil War and would not be assigned 4F or 4-F.

After the Civil War, the term 4-F (4F) continued to be used to disqualify possible recruits for medical, dental, or other health reasons.  As time progressed and more was learned about medicine and dentistry, new screening criteria was developed.  In addition, with the development of new rifle technology, one no longer needed four front teeth to efficiently fire and re-load a rifle.  So the “four front teeth” criteria was eliminated.  The term 4-F was used by the Selective Service System extensively in World War II and that is when it entered the vocabulary of most Americans.

As a general dentist in private practice, I have the privilege of treating all types of members of the Armed Services. Frequently I have to examine a patient and complete a Pre-Deployment Dental Screening Form and certify that the patient has no acute dental problems that would interfere with his/her ability to serve in the military. I feel honored to have this privilege and I take this responsibility quite seriously.  As of this day, I have yet to see a patient about to deploy without at least 4 front teeth. But if so, it would not disqualify them from service. But I hope I never see that!

Dental MythBuster #6 – My baby stole the calcium from my teeth!

As a general dentist practicing in Orange, CT, I have the privilege of treating patients of all ages, including both expecting and postpartum mothers.  The number one dental myth I hear from these patients is the following:

Drawing of baby who stole the calcium from his mother's teeth leading to dental cavities

“I didn’t have any cavities until I became pregnant. Then my baby sucked the calcium out of my teeth which is why I have all these new cavities now!”

This is always a difficult dental myth to “bust.” First, the concept of losing calcium from bones is well established and patients frequently assume bones and teeth are similar.   Secondly, this dental myth is so widely circulated among pregnant and new mothers that many don’t want to believe me when I try to “bust” it!

About Calcium, Teeth, and Bone

Teeth, like bone, are comprised of hard minerals, with calcium being one of the key components. Tooth enamel is harder than bone and is actually the hardest substance in the body!  Adult teeth begin to develop at a very young age and continue to mature until approximately age 16 (except for wisdom teeth).  By age 16, your teeth are no longer developing and the strong enamel layer no longer requires nutrients from your bloodstream.   So at this point a deficiency of calcium in your diet will not affect your teeth, because your teeth are no longer forming.

Picture of Bone in Thigh. Unlike teeth, bones are constantly being broken down for calicum.

Bone is used as a source of calcium.

This is in direct contrast to bone which is constantly being reformed in response to dietary, hormonal, and other factors. Every single day, small parts of your bones are naturally dissolved and then re-formed.  Calcium is needed for this process and a deficiency of calcium can lead to weaker bones.  This is one of the main reasons why older patients frequently take Vitamin D and Calcium – it is to enhance the strength of their bones.

So, many patients assume that because bones constantly require a source of calcium, then teeth must as well. And with a growing baby in utero and/or nursing baby taking nutrients from the mother, people assume their teeth are having nutrients taken away. Not true!

New Mothers and Tooth Cavities

So this brings up the question: do new mothers have greater amounts of tooth decay? And if so, why?  Well, the answer to the first question is Yes! New mothers do have higher rates of dental decay.

Tooth with a cavity or decay in a new mother, not because the baby stole her calcium

Photo of a tooth from one of my patients with an 8 month-old little one. The cavity is NOT because the baby “stole” calcium from her teeth!

There are several reasons for why new mothers have more cavities. I have observed all 4 of these personally in my private practice.

  1. Morning Sickness: not all pregnant patients experience this. However, even occasional vomiting in the morning brings up very acidic stomach contents which can quickly erode your teeth, leading to decay.
  2. Acid Reflux: pregnant women are more likely to experience acid reflux due to the pressure on their stomach from the growing baby. This can also lead to stomach acid entering the mouth to erode the teeth.
  3. Changes in Oral Hygiene: let’s face it, being a Mom is hard work! Many new mothers spend so much time focusing on their new child that they neglect to brush and floss consistently. This can easily lead to new cavities.
  4. Changes in Diet: with pregnancy and nursing, some women will start eating sugary foods they did not typically consume before.  Increased sugar intake can lead to increased decay.

In addition to dental decay, pregnant and nursing mothers are also at risk for Pregnancy Gingivitis which will be covered in a future post.