Antibiotics in Endodontics Killing the bugsWithout the drugs

Bacteria surround us:For billions of years, bacteria have inhabited the earth, but only since the beginning of the 20th century has mankind been fighting these organisms.

1928Penicillin discovered Beginning with the discovery of penicillin in 1928, antibiotics have been used to cure and control infectious diseases. But antibiotic treatment is a double-edged sword. As antibiotics continue to be used, bacterial resistance continues to grow.

Antibiotics use grow; bacterial resistance increases All organisms evolve to survive life-threatening circumstances. Unfortunately, bacteria are genetic overachievers. Bacteria have the ability to protect themselves through two processes: mutation and genetic transfer.

Antibiotics use causes:1. The longer a population of bacteria is exposed to an antibiotic, the more resistant survivors become. 2. Beneficial microbes are also killed by antibiotics. 3. When antibiotics are administered in doses small enough to allow stronger bacteria to survive, the selection process accelerates.

158 antibiotics currently available:There are currently about 158 antibiotics available ,and strains of bacteria resistant to each of these antibiotics have been identified. Unfortunately, it takes a lot of money and many years to develop new antibiotics. Because they can be rendered useless so quickly, few new drugs are under development.

One-third of all outpatient antibiotic prescriptions are not necessaryResearchers at The Centers for Disease Control estimate that one-third of all outpatient antibioticPrescriptions are unnecessary. As clinicians begin to understand the gravity of the situation, they are re-evaluating how and when to prescribe antibiotics.

Misconceptions about antibiotics:Many times, healthcare providers may prescribeantibiotics simply because patients request it, even when there is no clinical justification. It can be said that the general public has been misled to believe that antibiotics make:Faster recovery.Less painful recovery.More certain recovery.

Treatment +Immune system = Optimum + healingAntibiotics(when appropriate)

Antibiotics are an adjunct to treatment. It is the patients own immune systemthat helps the patient achieve optimum healing

Bacteria gain access to root canal system through:Caries.Exposed pulp.Cracks in dentin.Leaking restorations.Canals exposed by advancing periodontal disease.

Endodontics without antibiotics

When inflammation or infection is present, the circulation in the pulp is poor. And because Antibiotics are carried by the vascular system, their ability to reach bacteria in a strong enough concentration is diminished. For this reason, antibiotics are not Effective in endodontics.

Successful healing: can be achieved byOptimal debridement:Through debridement of the root canal system will help remove bacteria and their by-products from the canal space. This will help eliminate infection and inflammation and promote healing.

Optimal obturation:If the canal system is not obturated at the initial appointment, a medication such as calcium hydroxide may be placed inside the pulp chamber and root system 1. to fill the space, 2.to prevent recontamination, 3.and to kill remaining bacteria.

Well-placed final restoration:The medication should be covered with sterile cotton pellet and sealed with a temporary restoration at least 3mm in thickness. Successful healing depends on optimal debridement followed by a well-condensed root canal filling and final restoration.

Drainage through incision:Occasionally the infection will move beyond the tooth and bone, into the soft tissue. This can cause intraoral swelling.

Swelling can be treated with an incision and drainage. This will eliminate bacteria, relieve pressure, improve circulation and promote healing.

Appropriate antibiotic use:To justify the need for antibiotics, an infection must either be: persistent infection or systemic infection

Antibiotics are unnecessary for:Pain and Localized swelling.

do not necessitate antibiotic treatment. Most dental pain can be managed using non-narcotic analgesics such as NSAIDs.

Factors to evaluate:When determining if antibiotics should be used to treat a patient, several factors should be evaluated: Patients health. Is the patient in good health? If not, it is more likely that antibiotics will be needed.Development of symptoms: How rapidly did the symptoms occur? Swelling or fever that escalates within a 24-to 72- hour period may indicate that an infection is spreading, and antibiotics are likely needed.

Extent of inflammation: What is the extent of soft tissue inflammation? If swelling is localized, the infection may be managed by surgical drainage.. A large, diffuse swelling may require antibiotics as well as surgical drainage.Risk vs. benefits: It is also important to consider the benefits versus the risks of antibiotic treatment.Signs of systemic involvement.

Risks of antibiotics treatment:Allergic reaction: Approximately three to six percent of patients experience an allergic reaction to penicillin. This can range from a minor rash to a life-threatening anaphylaxis.Other side effects: Some patients experience side effects, such as gastrointestinal problems or secondary infections. Interference with other drugs: Women of childbearing age should be alerted of the possibility that antibiotics may interfere with the efficacy of birth control pills.

Systemic involvement warrants antibiotics:It is also important to determine if there are signs of regional or systemic involvement when prescribing antibiotics. Patients who have:Cellulitis or extraoral swelling.Lymphadenopathy.Elevated body temperature.Malaise.Unexplained trismus.Usually require antibiotic treatment and/or surgical drainage.

What are the antibiotics Used to manage endodontic infections

Penicillin VK:Penicillin VK is the drug of choice for the majority of oral infections. It is effective against most aerobic and anaerobic bacteria that are commonly present in the mouth.

Dosage:Penicillin VK:A loading dose of 1000 mg of penicillin VK should be given, followed by 500 mg every six hours for five to seven days.Consider contacting the patient after 24 hours to assess his or her condition. Improvement should be rapid. If there is no improvement after 48 hours, penicillin may be supplemented with metronidazole.

Metronidazole: Metronidazole is a synthetic antibiotic that is highly effective against strict anaerobes but is not effective against facultative anaerobic bacteria. If penicillin is ineffective after 24 to 48 hours, metronidazole is a valuable antimicrobial agent for combination antibiotic therapy.

Dosage:A recommended loading dose of 500 mg of metronidazole is recommended, followed by an oral dosage of 250 mg every six hours for seven to ten days.

Amoxicillin: It is a derivative of penicillin VK. It has a broader spectrumIt is better absorbed from the gastrointestinal tractIt provides a higher and longer sustained serum level. but Its use increase the antibiotic resistance.

Dosage for amoxicillin is similar to that of penicillin VK.Some practitioners may also choose to use cephalosporin in place of a penicillin-type drug.Dosage for cephalosporins is similar to that of penicillinVK.

Clindamycin: is good substitute for those allergic to penicillin.It is highly effective against strict and facultative anaerobesAlthough clindamycin has been linked with pseudomembranous colitis, studies show that colitis is a possible side effect of most antibiotics, such as amoxicillin and cephalosporin.

Dosage:A loading dose of 300 mg of clindamycin is recommended, followed by 150 mg every six hours for seven to ten days.

Erythromycin: Erythromycin is another antibiotic that is commonly prescribed for patients who are allergic to penicillin.Unfortunately, it has been shown to be ineffective against most of the anaerobes associated with endodontic infections, so other antibiotics are preferred.

Clarithromycin(Klaribac)Active against:Gram-positive + Gram-negativeAerobic & Anaerobic BacteriaKlaribac adult dose=250mg twice/daily, increased to 500mg if necessary; in severe infections for (7 to 14 days).

A recent article in the JOE showed:

Augmentin which is a combination of amoxicillin and clavulanateHas the best efficacy against bacteria isolated from endodontic infection and may be indicated to treat serious endodontic infection, especially in immunocompromised patients

Treatment regimens:Short and aggressive: Treatment regimens should be short and aggressive to minimize the development of resistant bacteria and to achieve a therapeutic concentration of the drug.

Patient compliance critical: The patient must understand that adherence to the dosing schedule is imperative to eliminate the infection.

Postoperative Endodontic PainAlthough some patients may experience moderate to severe pain after endodontic treatment ,very few experience what is now commonly referred to asFlare-up : a postoperative problem requiring an unscheduled dental visit with unplanned treatment to manage the patients symptoms .Numerous studies have evaluated factors related to postoperative endodontic pain and flare-up to better predict when these conditions are more likely to occur teeth with necrotic pulp

factors related to postoperative endodontic pain and flare-upthe presence of preoperative pain or mechanical allodyniateeth with necrotic pulp no correlation / the presence or absence of a periradicular radiolucency. that one-visit endodontic retreatment cases involving teeth with apical periodontitis had almost a tenfold higher incidence of flare-ups It is recommended that retreatment of teeth with apical periodontitis should not be completed in one visit whereas, treatment of teeth with AP can be done in one visit

Glucocorticosteroids Glucocorticosteroids are known to reduce the acute inflammatory response by several mechanisms. Therefore a number of investigations have evaluated the efficacy of corticosteroids (administered via either intracanal or systemic routes) in the prevention or control of postoperative endodontic pain or flare-ups.

Dexamethasone solutionformocresol (the corticosteroid antibiotic paste Ledermix, Intracanal steroids appear to have a significant effect in reducing postoperative pain.Systemic administration of dexamethasone Reduces the severity of postoperative endodontic pain. However, given the relative safety/efficacy relationship between steroids and NSAIDs, most investigators choose an NSAID as the drug of first choice for postoperative pain control.

Management of endodontic pain endodontic pain can be managed through combined endodontic procedures and pharmacotherapy. A major class of drugs for managing endodontic pain is the nonnarcotic analgesics, which include bothNSAIDs and acetaminophen

Selected Nonnarcotic analgesics

AcetaminophenAspirinDiclofenac IbuprofenNaproxen

Limitations and Drug Interactionsincluding those affecting the gastrointestinal system (3% to 11% incidence) and the CNS (1% to 9% incidence of dizziness and headache). NSAIDs are contraindicated in patients with ulcers and aspirin hypersensitivity

The NSAIDs interact with other drugs Summary of Drug Interactions Anticoagulants : Prolonged prothrombin time or increased bleeding with anticoagulants (e.g., coumarins)Angiotensin-converting enzyme (ACE) inhibitors: Reduced antihypertensive effectiveness of captoprilBeta blockers: Reduced antihypertensive effects of beta blockers (e.g., inderal,) Cyclosporine: Increased risk of nephrotoxicityDigoxin : Elevated serum digoxin levels

Acetaminophen and opioid combination drugs

are an alternative for patients unable to take NSAIDs. Further information is available from a number of sources on the pharmacology and adverse effects of this important class of drugs Other resources are also available for evaluation of drug interactions, including Internet drug search engines such as rxlist.com, Epocrates.com, and Endodontics.UTHSCSA.edu.

Antibiotics to manage flare-ups?Clinical trails have shown that administering antibiotics before treatment does not reduce the incidence of flare-ups following treatment. To justify the use of an antibiotic in the management of a flare-up, an infection must either be persistent or systemic.

Case study # 1:23-year-old man.Tooth hit with baseball.No luxation.Localized swelling.Because the swelling was localized, the tooth was drained through an access opening on the lingual surface and the swelling was reduced significantly. Root canal treatment was successful without the use of antibiotics.

Case study # 2:45-year-old woman.Severe toothache.Deep carious lesion.Large, diffuse swelling. fever,lemphadenopathyTX: an incision for drainage. A loading dose of 1000 mg of penicillin was prescribed, followed by 500 mg every six hours. The case was completed in 10 days and the patient was symptom free.

Responsible use of antibiotics is up to all of us. By stimulating the development of resistant strains of bacteria, these medications permanently alter the microbial environment.Dentist, physicians and patients have a serious responsibility to understand why antibiotics must be administered with caution and to adhere to the principles that govern their appropriate use.