How to Give a Painless Injection [Part IV]
You know the kind of patient I’m talking about. You can give them enough anesthetic that their toes are numb but as soon as you touch the tooth, you have to peel them off the ceiling. So what can we do to make these hard to numb patients comfortable?
First, let’s look at smokers. This one is easy; ask them not to smoke for two to three hours before their appointment. Nothing guarantees a bad appointment more than a smoker having a cigarette right before. I have listed in my pretreatment brochure not to smoke since it can interfere with the efficacy of the anesthetic.
I’ve had a number of patients that couldn’t get anesthetized due to smoking. After I reappointed them and explained for them not to smoke, they were able to get comfortable after one shot. Smoking changes the liver enzymes and increases blood flow which causes faster metabolism of the anesthetic.
Now what about the ones that don’t have a discernable cause of anesthetic resistance? I mentioned buffering in Part II with regards to taking the burn out of the injection. One other benefit of buffering is faster and stronger onset of anesthetic. This property helps with hyperemic teeth and infected sites. The buffering helps disassociate the anesthetic ions faster allowing for faster onset and more profound anesthesia.
Have you ever heard of the x-tip? This little beauty is awesome for getting fast profound anesthesia. It is an intra osseous injection system. It contains two components: a drill for the slow speed hand piece used to create a hole in the cortical plate, and a very short needle to fit into the hole.
The process starts with numbing the soft tissue with a small amount of local anesthetic then taking the drill in the slow speed and making a pathway approximately 2-3mm below the papillae in the attached gingiva next to the tooth you want to anesthetize. The drill is specially designed to leave a guide device in the bone to aid in getting the needle oriented correctly for administration of the anesthetic. The needle is then slid through the guide path and anesthetic is administered; onset is rapid and profound.
Maxillary teeth usually will respond to one of the techniques above, but mandibular teeth are a different story. So what happens when none of this works on a mandibular tooth? Now you have to bring out the big guns. This is where the Gaw-Gates injection comes into play. This is a standby for me when doing long or very involved surgical procedures.
I’ll use two different anesthetics when trying to get the difficult patient numb. I start with 3% mepivicaine without epi followed by 2% lidocaine with 1:200000 or 1:100000 epi. The mepivicaine is faster acting and has a larger distribution area from the lack of epinephrine. This gets the patient anesthetized quickly allowing me to start, but lasts long enough to overlap with the onset of the lidocaine.
Darin O’Bryan, DDS [ www.onemorereasontosmile.com ]