Basically, anesthetic solutions in dentistry are administered in two routes,
* Intra-oral, meaning into the mouth and
* Extra-oral, meaning outside the mouth on certain areas on the face.
The intraoral route is by far the commonly used route of anesthetic administration in dentistry. Again, depending on the procedure to be performed, the areas of administration vary. If a single and very mobile tooth is to be pulled out, then the area around the tooth is singularly anesthetized. Where as multiple extractions or complex surgical procedures require one side of the face to be anesthetized. This is done by injecting the solution close to the nerve, which supplies these areas of the mouth. The effects of the anesthesia last from 2-4 hours though it can either last longer or shorter depending on the concentration of the anesthetic agent.
Contraindications and complications
As such there is no absolute contraindication to the administration of anesthetic agents. There however exist some conditions where it is not advisable to give the full concentration of the drug. High blood pressure or hypertension is one such condition where adrenaline is not included in the anesthetic solution. All the other components are the same. Another condition is allergy to the solution. If the allergy is acute then local anesthetics are abandoned and general anesthetics are chosen. Complications of dental anesthesia mainly have to do with the inadvertent injection into a blood vessel. In such a case, a hematoma develops with subsequent swelling and pain. This however is treatable and goes away in no time.
Latest activity in the field
Jet injectors have been developed so that even the pain of the needle prick is not felt. Since the administration of the injection is basically a blind process in that dentists actually do not know if the needle has gone into a vessel, efforts to incorporate a microchip connected to a monitor are being pursued. This will allow dentists to actually see where their needle has gone and could cut down the risk of injecting into a blood vessel.