The two procedures that make up Field Dentistry are fillings and extractions. Field Dentistry is defined as providing your own dental care when there is no other way; probably due to collapse of our health care system along with the rest of our fragile economy and civilization due to the disastrous economic policies of our “leaders”, a terrorist attack, or some other reason.
Fillings can be easy or complicated depending on the size of the cavity and the surfaces of the tooth that are involved. Starting with the simplest- a one surface cavity in the chewing surface of the tooth, here is how it can be fixed. A dental instrument called an excavator is used to remove decayed tooth and any debris that is in the tooth. The instrument has small spoon shaped ends that have an edge and will remove decay easily, but sound tooth structure is harder and the difference is easily detected after a little experience. Once the decay is removed, a filling is placed. This is where the difference in Field Dentistry and office dentistry is pronounced. In an office under a controlled environment, a composite filling that will last many years can be placed. This requires the ability to etch, dry the surfaces, place bonding agent, light cure it, place composite, light cure it, and finish it down using the drill to shape it to match the bite of the patient. These steps are close to impossible to accomplish in the field without electricity. There are battery powered devices for part of the procedures mentioned, but not for all. If the cavity is not kept dry during most of the steps, the composite won’t bond and the filling will either come out or leak and get decay around it very soon.
Here is what can be done in Field Dentistry. The cavity is dried with a cotton pellet. A Temporary Filling Material (TFM) such as Cavit is placed in the cavity using a Plastic Filling Instrument. The instrument is made of stainless steel. It got its name when the first white fillings were called plastic fillings. The instrument has a paddle shaped end which is used to carry the TFM to the cavity and placed by putting the TFM in by pushing it into the cavity with a simultaneous wiping motion against the edge of the cavity. The TFM has a consistency before setting similar to toothpaste but a little more viscous. It is sticky and will stick to the instrument instead of the tooth without the above mentioned technique. The other end of the Plastic Filling Instrument has a flat condensing end and is used to make sure there are no voids in the material by condensing it into the cavity. It is also used to shape the TFM to match the original anatomy of the tooth surface. The margins where TFM and tooth come together are important and should be well adapted because any gaps here will reduce the quality of the filling and shorten its life. Gaps increase the possibility of recurrent decay. After the filling is placed, the patient bites and grinds shaping the filling to the patient’s bite so there won’t be any high spots. After this is accomplished the TFM can be smooth by wetting your gloved finger in the patient’s salvia and rubbing it across the filling. If you have a cotton swab, it can be wet and used the same way. The patient should then wait at least an hour before chewing to allow the TFM to harden. It hardens on exposure to moisture, so drinking liquids is OK, just no chewing.
Though TFM is not made to last nearly as long as composite fillings, its ease of placement and forgiveness of mistakes in placement make it a very good material for Field Dentistry fillings. It could last about six months, and if small sometimes longer. Cavities between the teeth are treated in a similar manner in Field Dentistry, but placement of the TFM will be more difficult. TFM sticks to teeth well when soft, but it doesn’t have much adherence when set, so the shape of the cavity needs to help in retention of the cavity.
The best material for Field Dentistry fillings is a zinc oxide powder eugenol liquid material that sets much harder than TFM. Directions that come with the kit are followed in measuring and mixing, then the material is placed like TFM. It sets in a few minutes after mixing, so adjustment to the patient’s bite needs to be accomplished before it sets as much as possible. Once it sets, if it is high and interferes with the patient’s bite, it must be shaped with an instrument called an Amalgam Carver. This has a disc shaped end and a sharp pointed spade-shaped end and can be used to carve off any part of the filling that interferes with the patient’s bite. If the filling is high, it can created worse problems than a cavity, causing excess pressure on the tooth, and also tooth grinding or clenching that creates pain in the TMJs (Temporomandibular Joints) both of which are worse that having a cavity. THE TMJs are the joints right in front of the ears on both sides. The zinc oxide-eugenol mix is a little more technique sensitive, so the best Field Dentistry kit will include both it and TFM along with the necessary instruments.
Having the correct materials and instruments and knowing how to use them are critical in effective Field Dentistry. Dental School takes four years after college, but learning some of the basics is much better than having no idea of what to do when dental care is needed. The instruments mentioned above are stainless steel, the same as I use in my office, and can be autoclaved repeatedly. A pressure cooker-canner makes a good autoclave. The excavator and amalgam carver can be periodically sharpened using a stone that is used to put a final edge on a knife blade, because like a knife they get dull with use and should be fairly sharp. An excavator is sharp enough when it will carve off a little bit of fingernail when scraped across the flattest part.
Long after all filling materials are gone, teeth can be extracted when necessary. We will be back to the level of dentistry of the nineteenth century when teeth were extracted because there was no alternative. Extracting teeth should not be done with anything except forceps that are made for that purpose. The shapes of the beaks may look like pliers, but they are different, and the difference is critical. The forceps are made to grip the tooth as far down on the root as possible to give the best leverage. Pliers and vise-grips will crush the tooth and break it off most of the time and should not be used unless they are all you have; but be aware of their limitations.
I have been in dental practice for 31 years. I will have at a minimum for Field Dentistry in my kit the following: 1) Basic Kit for fillings, re-cementing crowns and bridges, and treating some toothaches, 2)Extraction Kit with three forceps, a curette, and an elevator, and 3) a Zinc oxide-eugenol kit for fillings. These are compact in their roll-up nylon holders and even in a mobile situation on foot they won’t take up much room in my pack or weigh too much to carry with me.
If you have ever had a toothache, you know how important it is to have it treated. The pain is so intense it interferes with camp security and even regular camp chores. Don’t neglect Field Dentistry in your preparations.
Instruction on extracting teeth is planned for a future article.