Local anesthesia and the team

July 1, 2002
Readers who are licensed to administer local anesthesia may be surprised to know that there are still a handful of states - including Texas and New Jersey - that don't yet allow hygienists to administer local anesthesia.

Readers who are licensed to administer local anesthesia may be surprised to know that there are still a handful of states - including Texas and New Jersey - that don't yet allow hygienists to administer local anesthesia.

Can you believe that? What are they so afraid of? In some states, hygienists have been giving local anesthesia - safely and effectively - for more than 30 years. Local anesthesia by hygienists should be part of every state practice act.

It is hard to understand why dentists in some states are so afraid of this issue. Some say they feel it is just a step toward independence, although there is no evidence to support that idea. Hygienists in Washington State have been giving local anesthesia since 1971, and are still working with dentists.

Some dentists feel hygienists aren't capable of administering local anesthesia - but there is no evidence of that, either. Several studies have shown that hygienists who give local anesthesia are extremely safe and effective. It is clear that hygienists with proper training are just as capable of handling this procedure as dentists are. Studies evaluating local anesthesia complications report much lower rates for hygienists than for dentists. Emergency situations range from fainting to patient death.

There really isn't a valid argument against hygienists giving local anesthesia. The real reason must be fear of change itself. After all, the one who stands to gain the most from hygienists giving local anesthesia is the dentist.

Instead of making hygienists more independent, local anesthesia has strengthened the team approach between hygienists and dentists. While hygienists use local anesthesia for perio procedures or to reduce sensitivity, quite often they use it for restorative patients - the dentist's patients. If the hygienist has time, while the dentist does an exam on a hygiene patient, the hygienist can go into the other operatory and administer local anesthesia for dentist's patient. If a restorative appointment follows a hygiene visit, the hygienist will likely anesthetize the patient before the dentist begins the procedure to allow enough time for the anesthesia to take effect. It's teamwork.

Besides providing anesthesia for the dentist's patients, dentists no longer have to stop what they're doing to anesthetize hygiene patients. This aspect is especially important for periodontists who employ several hygienists. It saves the dentist time all around. Why wouldn't they want that?

What I find interesting is that hygienists must pass both a written and a practical local anesthesia exam before being licensed. Dentists aren't tested on their local anesthesia skills, either in school or on state boards. It's simply a rite of passage for them - if they graduate from dental school, they're qualified.

However, I also believe that dentists are the biggest supporters in states where local anesthesia is legal for hygienists. I remember a time many years ago when the American Dental Association suggested that states with local anesthesia should work to reverse the law, taking the responsibility away from hygienists. That idea didn't get very far in Arizona. It was the dentists who spoke up in favor of hygienists giving local anesthesia.

Anesthesia news

Did you know that rotation of the needle on insertion reduces the pressure exerted and avoids needle deflection? Two years ago, Drs. Hochman and Friedman proposed a bi-directional rotation of the needle as it is inserted to avoid needle deflection. Using radiographs, they were able to document a straight needle path when the needle is rotated on insertion, compared to the curved path of needle deflection seen with the traditional linear insertion.

Here's how the technique works. You rotate the syringe counter-clockwise and then clockwise, while inserting the needle. It can also be done in just one direction. The concept is similar to coring an apple, with a rotating motion rather than simply pushing straight on. If you picture the bevel on the needle, a traditional insertion is easily deflected, but the rotation of the needle keeps the tip of the bevel pointing straight ahead.

In their most recent work, Drs. Hochman and Friedman showed that as the needle is deflected, more force is needed to advance the needle. They did this in laboratory tests, comparing insertion pressure between these two insertion techniques. To simulate human tissue, they used unpeeled bananas and hotdogs. Using various needle gauges (25, 27 and 30), they performed 400 needle insertions using a device to measure insertion pressure.

The traditional linear insertion required two to three times more pressure compared to the rotational insertion, regardless of the needle gauge used.

Next time you administer local anesthesia, observe your insertion technique to see if you are already rotating the needle or if your technique is strictly linear.

Have you ever tried an intraligamentary injection - also called a periodontal ligament injection? Probably not, since you were told the pressure of the trigger-operated syringes exerted too much force, damaging the periodontal ligament. Check out the Citojecttrademark from Athena-Champion and available from your local dental dealer. I liked this syringe so much I bought my own years ago.

The barrel shape looks like a highlighter with a lever on the side, which is depressed by the index finger. It holds a carpule in the enclosure and uses extra short 30-gauge needles. If you want to anesthetize a deep pocket, then a longer needle is recommended. The lever makes expelling the anesthetic solution much easier than with a traditional syringe, so care must be taken to depress it slowly, depositing just a drop at a time.

The clinician is totally in control of the anesthetic flow.

It's great for localized pockets, especially on the lower, when you would rather forgo the numb lip associated with the inferior alveolar block, just to treat an isolated area. One slow depression of the lever deposits enough anesthetic solution to achieve profound anesthesia on a single rooted tooth. For multi-rooted teeth, a lever depression is needed for each root. It's very good for palatal injections and ideal for restorative procedures or extractions on children.

The two newest syringes are the Wandtrademark and the Comfort Controltrademark, which are electronic computer-controlled devices that slowly deliver a set amount of anesthetic solution at a comfortable rate. We'll see more use of these in the future.

Pain control using local anesthesia is an important part of dental hygiene practice. It is now part of the regular curriculum in many dental hygiene schools, and I anticipate that those few states that are dragging their feet on this issue will soon join the trend of the past 30 years, allowing hygienists to administer local anesthesia.

Trisha E. O'Hehir, RDH, BS, is a senior consulting editor of RDH. She also is editor of Perio Reports, a newsletter for dental professionals that addresses periodontics. The Web site for Perio Reports is www.perioreports.com. She can be reached by phone at (800) 374-4290 and by e-mail at [email protected].