AN ENDODONTIST'S ADVICE

Edward F. Rosenfeld, DMD, MS, is a Denver-based Endodontist, who recently retired after more than 34 years in practice. Apart from having owned his own, very successful private practice, Dr. Rosenfeld is a past clinical instructor to the Dental residents at Denver General Hospital and has also presented many lectures and seminars before the Alpha Omega Dental Fraternity, Metropolitan Denver Dental Society, Rocky Mountain Society of Endodontists and other local study clubs.He is a member of many Professional Associations including the American Dental Association, American Association of Endodontists, Colorado Dental Association, Metropolitan Denver Dental Society and the Denver Academy of Clinical Dentistry. He received the 2006 Honus Maximus Award honoring individuals who have contributed to the advancement of the profession of dentistry, or to major improvements in the oral health of the community. The Honus Maximus Award is the highest honor the Metropolitan Denver Dental Society bestows on its members.
My special thanks to Dr. Rosenfeld for writing the 3 Endo articles especially for my dental blog. It is my privilege to have had the opportunity to work with such an esteemed Endodontist and a marvelous human being.

Treating Cracked Teeth

Your patient is complaining about chewing sensitivity. The radiograph shows the PA area to be normal and the tooth responds to cold without any lingering pain. A clinical examination discloses a M-D fracture on the marginal ridge. The proper treatment is to crown this tooth. According to Krell and Rivera, JOE December 2007, and based upon a six year study, 80% of these teeth survive without needing root canal treatment. Of the remaining 20%, the need for endodontic treatment becomes apparent within the first six months. Of course, if the tooth tests with lingering pain to cold or if it does not respond to thermal testing, then root canal treatment must be performed before the crown is prepared. Also, the prognosis for cracked teeth is determined by the depth of the crack. If a narrow, deep periodontal pocket can be probed or if the PDL appears very wide, or if a radiolucency is apparent in the furcation, then the prognosis for a successful root canal treatment is guarded.


Antibiotic Use And Misuse in Endodontics

Your patient complains of a toothache which is intensified by cold liquids. The tooth is percussion sensitive and a thickening of the PDL is present.

A carious lesion is evident which extends into the pulp. The patient is NOT medically compromised. Do you prescribe an antibiotic? This condition clearly DOES NOT call for the use of antibiotics yet we still see patients arriving for emergency treatment with a new prescription for Penicillin or some other antibiotic. The situation above concerns a vital pulp. There are few, if any, bacteria present in the pulp. The proper treatment is to perform emergency endodontic therapy or complete single-visit endodontic therapy, prescribe an analgesic such as Ibuprofen and provide reassurance to the patient, There is currently an antibiotic crisis in this country as a result of misuse and overuse. Low doses of antibiotics are present in the food we eat. The result of the above is antibiotic resistance. New strains are mutating faster than the drug companies can develop new antibiotics. Let us not contribute to the problem by prescribing them when they are not indicated or by prescribing the wrong drug or an inappropriate dose when they are indicated. These are some other endodontic situations where it is inappropriate to prescribe antibiotics: Non-vital pulp with a chronic, draining sinus tract (fistula).
Non-vital pulp in a healthy patient without any swelling.
The proper treatment is to remove the pulp through thorough debridement. If you wish to place an intracanal medicament, you may use Calcium Hydroxide or Vitapex. Single-visit endodontics may also be performed. What situations may or may not call for the use of antibiotics?
Non-vital pulp with good drainage upon opening the tooth.
Non-vital pulp with fluctuant swelling where an incision and drainage is performed.
Re-treatment of a failing root canal treatment. These situations most often require appropriate antibiotic coverage:
Pre-medication situations, ie: cardiac prophylaxis
Non-vital pulp in a medically compromised patient.
Non-vital pulp with an indurated, non-fluctuant swelling.
Post-treatment swelling.
In these situations often there is a fever present of greater than 100 degrees F., malaise, lymphadenopathy and trismus may also be present. What is the first line for empiric antibiotic therapy?
Penicillin VK 500 mg q 4-6 h (1000 mg loading dose) Narrowest spectrum
Amoxicillin 500 mg q 8 h (1000 mg loading dose) Broader spectrum and less desirable.
Azithromycin (Zithromax) 250 mg q24h (500 mg loading dose) for milder infections. If a patient is allergic to or not responding to the above, the second line is:
Add Metronidazole (Flagyl) 500 mg q6h (1000 mg loading dose) to Pen VK or prescribe Clindamycin (Cleocin) 300 mg q6h (600 mg loading dose) Any antibiotic therapy should be continued for three days after the major signs and symptoms have disappeared.


Minimizing the Fracture of Rotary Endodontic Instruments

The key is to create a glide path to the apex. Despite the advancements in NiTi endodontic rotary instruments, there is no substitiute for hand instrumentation. One or more well-angulated radiographs helps to indicate potential anatomic problems. After adequate access is established, I add RC Prep or some other EDTA paste preparation and using a gentle slight back and forth rotation of the #10 file coupled with an in and out motion, slowly advance this file to within five mm of the estimated root length. This is repeated with the #15 and #20 hand files. At this point, an electronic length is obtained with the Root ZX (J Morita) or another late generation electronic apex locator, while using the #10 file. This is followed by further filing with the hand files and EDTA using sizes #' 10-20 at the least. I will often use the #25 and #30 to flare the canal short of the apical measurement. At this point, with a glide path established, you can switch to irrigating with sodium hypochlorite and begin the use of your NiTi rotary instruments. Use these instruments in an electric handpiece with a low torque control setting with auto-reverse and advance them with a slight in and out motion. Toss these instruments after three uses in molars.