spectrum agents such as sulfamethoxazole/trimethoprim (Bactrim ® , Septra ® , and others) and the tetracyclines (tetracycline, doxycycline, and minocycline) can cause collateral damage (superinfection by resistant pathogens, or selection of antibiotic resistance) since these agents are less targeted in their microbial selection when compared to narrow-spectrum
antibiotics. Low-dose tetracyclines such as sub-antibiotic doses of doxycycline have been used to treat periodontal disease; however, this activity is based on anti-inflammatory properties of the medication rather than antibacterial properties (Bretz, 2012; Castro et al., 2016; Madi, Pavlic, Samy, & Alagl, 2018).
APPROPRIATE TIMING OF ANTIBIOTICS
Timing is an important consideration in determining both when to begin an antibiotic and when to discontinue an antibiotic. Consensus exists among published guidelines with respect to prophylaxis , in that antibiotics should be started within 30 to 60 minutes prior to the start of the dental procedure in those patients at risk (Gould et al., 2006; Roberts, Ramsdale, & Lucas, 2004; Wilson et al., 2021). In 1990, Berney and Francioli evaluated the efficacy of single- dose amoxicillin in rats with catheter-induced aortic vegetations either 30 minutes before or 30 to 240 minutes after bacterial challenge. These vegetations were introduced intravenously with various inoculum sizes of tolerant Streptococcus sanguis or Streptococcus faecalis (Berney & Francioli, 1990). This work verified the effectiveness of the antibiotic as being protective even when given up to 2 hours postoperatively, confirming empiric preoperative antibiotics as the gold standard for infective endocarditis (IE) prophylaxis. In the case of prescribing an antibiotic for the treatment of an acute orofacial infection, antibiotics should be started as soon as possible after any surgical intervention such as incision and drainage. Antibiotic selection can be made empirically based on the suspected pathogen(s); however, samples such as blood, tissue, or sputum should be obtained prior to starting the antibiotic if diagnostic confirmation is desired for culture and sensitivity testing. Treatment of an acutely ill patient should not be delayed, however, while awaiting the results of these bacteriologic tests because the results may take up to 2 days and most patients will have defervesced within the first 48 hours on empiric therapy; the culture and sensitivity data simply confirm that the appropriate antibiotic was chosen. If the initial empirical choice was an extended-spectrum or broad- spectrum agent, the practitioner may decide either to continue therapy or change to a more narrow-spectrum agent. If there has been no improvement in the patient’s condition within the initial 48 hours, however, then the results of the bacteriological tests should help guide the prescriber to an alternative therapy. While the appropriate time to discontinue an antibiotic may seem self-evident as the medication should no longer be needed once the patient is clear of the infection, prescribers seem less assured as to when this actual time should be. Furthermore, in the ambulatory setting, not all patients can be relied upon to independently determine when this actual time should be, either. In their review on this subject, Rubinstein and Keynan (2013) found that most treatment periods that appear in textbooks are lacking in scientific evidence. Similarly, duration of treatment in therapeutic guidelines is most commonly Indications for antibiotic use As previously mentioned, antibiotics are either required for treatment of an existing infection or as prophylaxis for a potential infection, depending on the immunocompetency of the patient. Typical adult and pediatric antibiotic prescriptions for treatment of orofacial infections with all of these agents are listed in Table 4.
based on expert opinion. In this era of increasing bacterial resistance and rising hospital costs, there is a definite need to reevaluate the duration of antibiotic therapies for common infections. This issue was raised and solved many years earlier for common community-acquired infections (i.e., tuberculosis, malaria, sexually-transmitted diseases, and parasitic diseases), mainly because of cost and issues of adherence to treatment. Rubinstein and Keynan concluded that since shorter durations of therapy are not necessarily in the interest of the pharmaceutical industry, non-industry-sponsored, multicenter studies need to be conducted before resistance acquisition makes these issues obsolete. Recent advances in the evaluation of circulating biomarkers as surrogates for infection may further help define the appropriate duration of antimicrobial treatment (Aabenhus, Jensen, Jørgensen, Hróbjartsson, & Bjerrum, 2014; Singh & Koyfman, 2015). Even though traditional clinical signs for the diagnosis of infection – such as increased heart rate, fever, and leukocytosis – are well known, they are nondefinitive. The biomarker procalcitonin can significantly improve the accuracy of the diagnosis of infections, possibly even before classical or clinical laboratory manifestations. This fact can help optimize the timing of the starting and stopping of antimicrobial treatment. Until this type of testing becomes more widespread and economically viable, however, prescribers are left with counseling patients to either take all of the medicine as prescribed until the course of antibiotics is finished (i.e., for a 5-day, a 7-day, or even a 10-day treatment duration) or to consider stopping their antibiotic prescriptions 48 hours after symptom resolution. While instructing patients on the latter is preferred to help control the development of antibiotic resistance, reduce side effects, and limit potential superinfections that might result from needless overexposure to antibiotic treatment, most patients expect to complete a full course of antibiotics once they have paid for their prescription. In either case, the risk versus benefit must be considered, and as Rubinstein and Keynan and others have established, there is strong evidence to suggest fewer complications and similar outcomes with less antibiotic use. For this reason, shorter antibiotic treatment courses are becoming the standard of care (Rubinstein & Keynan, 2013; Hedrick et al., 2006; Hanretty & Gallagher, 2018; Muff et al., 2021). A recent systematic review and meta-analysis came up with the same conclusions in regards to antibiotic prophylaxis regimens following ear, nose, throat, and oral and maxillofacial surgery (Oppelaar et al., 2019).
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