Tags Posts tagged with "Local Anesthetic"

Local Anesthetic

31
Dental Suction Dentists Suctioning
©Racorn/Shutterstock.com

A reader named Jeanny recently emailed me the following questions:

Why is it necessary to suction after local anesthetic?
Why is it necessary to suction when doing a filling?
Can blood be involved in both of the above procedures?

I’ll answer the first two questions later on in this article.  In response to the last question, blood can be involved when giving anesthetic and doing fillings, but many times it is not.

First, let’s talk about the two main types of suctions that dentists routinely use.

The Two Main Types of Dental Suctions

Dental SuctionThere are two main types of dental suctions that dentists use: the saliva ejector and the high volume suction.

The saliva ejector does exactly what its name implies; it sucks saliva out of the mouth.  This is the suction pictured at the upper right of this article.  Many times dentists will have the patient close down on this suction so that it can suction away any remaining saliva in the patient’s mouth.

The other main type of dental suction that we use is the high volume suction.  This suction is so strong that the dental assistant simply holds it close to where the dentist is working and it will suck away any nearby debris, much like a strong vacuum cleaner can suck away crumbs without actually touching them.

You can see the high volume dental suction pictured below – try to pardon the lack of glove use by that dentist!

Dental Suction - High Volume

Why Dentists Use a Dental Suction

Now that the introductions are over, let’s talk about some of the different reasons why dentists will use a suction.

For Patient Comfort

Keeping the patient comfortable is a high priority.  In response to Jeanny’s question, we suction after giving anesthetic because the anesthetic has a bitter taste, and most patients prefer to rinse out with water and use the saliva ejector.  Also, if the anesthetic sits in the back of your mouth for too long, it may start to slightly numb the back of your mouth and could give the patient a gagging sensation.

We will also use the suction to make sure that you don’t get too much water in your mouth while we are working.

To Clean Away Any Excess Dental Materials

When a dental hygienist cleans and polishes your teeth, you can get a lot of cleaning paste in your mouth.  We use the suction to help clean all of that away.  Also, when dentists are do amalgam fillings, pieces of the soft amalgam can sometimes fall away from the tooth surface.  We use the suction to help whisk them away.

To Keep The Tooth Dry

During some procedures, such as white fillings, it is important that the tooth stay clean and dry.  The suction helps keep the tooth dry by sucking away any saliva, blood, and water that may have accumulated around the tooth.  If the cavity went below the gum-line, then it’s pretty likely that the gums will bleed during the filling.

To Help the Dentist See

As I mentioned in a previous article about the dental drill, the drill that dentists use to do fillings sprays out a lot of water to keep the tooth cool and clean.  Unfortunately, that water can quickly build up in the mouth and get on the dental mirror.  In order to ensure that the dentist can see the tooth while working on it, it’s necessary to use the high volume suction to suck away all of that debris.

Those are the four main reasons that I came up with as to why dentists use the dental suction.  In conclusion, let’s take a look at a question that I asked my dental hygienist as a child.

Where Does The Stuff Go After It’s Sucked Away?

I remember sitting in the dental chair in Dr. Arnold’s office as a child wondering what happens to all of the stuff that gets sucked down the suction.  Maybe I was hoping that the tooth fairy would somehow be able to save the bad part of my baby tooth that the dentist removed and put it back together once my tooth fell out.  After gathering up the courage to ask, I think I was slightly disappointed by the answer.

After your saliva, tooth debris, etc. gets sucked away, it travels through the suction line to a vacuum separator that will separate out any solids.  After that, your spit makes a journey down the pipes and into the sewer system.

It is now recommended that dentists install amalgam separators in their suction lines to separate out any dental amalgam and keep it from getting into the public sewer systems.

Questions?

Do you have any questions about why dentists use suction?  Leave a comment below and I’ll try to get back to you.  Thanks for reading!

Baby Teething Gel and Methemoglobinemia
©Jandrie Lombard/Shutterstock.com

Imagine waking up in the middle of the night to an upset teething baby.  You stick some Orajel in the baby’s mouth and go back to bed for some sleep.  The next morning, you realize that your baby isn’t breathing.  Although rare, this can happen.

Teething BabyLast month, the FDA spoke out about a certain complication known as methemoglobinemia that can occur with Orajel and other popular baby teething gels on the market.

Methemoglobinemia occurs when hemoglobin (the protein in blood that carries oxygen) gets modified so that it can’t carry oxygen to the body as effectively.  Because we all need oxygen to survive, methemoglobinemia is a potentially fatal disease.

Any teething gel that contains benzocaine can cause methemoglobinemia.  This includes such brands as:

The complication that can occur with baby teething gels is due to the local anesthetic, benzocaine, which teething gels use to cause a numbing sensation in your teething baby’s gums.

In their warning, the FDA states: “Methemoglobinemia has been reported with all strengths of benzocaine gels and liquids, including concentrations as low as 7.5%. The cases occurred mainly in children aged two years or younger who were treated with benzocaine gel for teething.”

In case you’re wondering, the strength of benzocaine in Orajel Baby teething gel is 7.5%.  Here’s the Drug Facts label for Baby Orajel if you’d like to take a look.

Symptoms of Methemoglobinemia

If you’ve used a lot of teething gel on your teething baby, it’s important to look for the following symptoms, which can be a sign of methemoglobinemia:

  • Pale, grayish-blue skin, lips, and finger/toe nail beds.
  • Shortness of breath
  • Tiredness and fatigue
  • Rapid heart rate
  • Confusion
  • Headache
  • Lightheadedness

If you believe that your baby has methemoglobinemia, it is important to seek medical care immediately.

How to Prevent Your Teething Baby From Getting Methemoglobinemia

The best way to prevent your teething baby from getting methemogloginemia would be to simply not use teething gels.  The American Academy of Pediatric Dentistry says that you can simply massage your baby’s gums or give them a chilled teething ring.

Looking for more ways to calm your teething baby without using Orajel?  Check out the article, Eight Natural Teething Remedies to Help Your Teething Baby.

Conclusion

If you want more information about Methemoglobinemia and teething gels, you can check out this news release from the American Dental Association.

It is important to remember that any drug that you give your child can have serious side effects.  Make sure that you are an informed parent by learning about each drug you give your child – not just teething gels!

Do you have any questions, comments, or concerns about methemoglobinemia and teething gels?  I’d love to hear what you have to say in the comments section below.  Thanks for reading!

Dental Anesthetic Makes Your Heart Beat Faster
©Nejron Photo/Shutterstock.com

You may have noticed that when you get a dental injection, sometimes your heart feels like it’s going to beat right out of your chest.  You’ve probably just assumed that your heart is beating so hard because you’re nervous.

That’s partly true, but there’s another reason — the dental anesthetic actually contains something that makes your heart beat faster!

Why Your Heart Beats Faster When You Get a Dental Injection

Dental InjectionAs I mentioned above, nervousness may play a role in making your heart beat faster when you get a dental injection.  When we get nervous, our heart beats faster because our body sends out a substance called adrenaline that increases our blood pressure and causes our heart to race.

Most of the local anesthetics used in dentistry in the United States contain epinephrine (also known as adrenaline.)  Not only is your body causing your heart to speed up by releasing adrenaline, your dentist is giving you adrenaline in the local anesthetic!

Don’t worry, dentists don’t want you to have a double-dose of adrenaline to make you nervous.  Local anesthetics contain epinephrine for another reason: The epinephrine constricts your blood vessels.

With your blood vessels constricted, the local anesthetic stays near your tooth for a long time.  That way, it gives your dentist a lot of time to work on your tooth without you feeling it.  Another reason that dentists want your blood vessels constricted is so that only a small amount of local anesthetic gets absorbed into your body.

Conclusion

You may have felt your heart pounding more during some dental injections more than others.  If the dentist happens to inject the local anesthetic into a small blood vessel, it can quickly travel to your heart and cause it to beat very hard and fast.  This generally subsides after 10 seconds or so and is not dangerous to you.  Most of the time, the local anesthetic is not injected directly into a vessel and stays right near the nerve without affecting the heart.

Have you ever felt your heart race when getting a dental local anesthetic injection?  I’d love to hear your comments and questions in the comments section below.  Thanks for reading!

Update 2/25/13 – I wrote a new post about why dental anesthetic makes your heart beat faster, with more science to back it up after some comments below made me question whether or not this can really happen. You can read it here: Can Dental Anesthetic Really Make Your Heart Beat Faster?