A review of commonly prescribed oral antibiotics in general dentistry.

The microflora associated with odontogenic infections are typically mixed and of indigenous origin. Streptococcus, peptostreptococcus, peptococcus, fusobacterium, bacteroides, and actinomyces species are the principle microflora isolated from these infections. Penicillin V (phenoxymethyl penicillin) remains the antimicrobial of choice for the initial empirical treatment of odontogenic infections. This agent is safe, highly effective and inexpensive. Amoxicillin has little indication for the routine treatment of odontogenic infections. However, it is the agent of choice for endocarditis prophylaxis, as it produces higher serum levels than penicillin V. Erythromycin may be used for mild, acute odontogenic infections in penicillin-allergic patients. The high incidence of gastrointestinal disturbances and superinfection commonly associated with the ingestion of tetracycline limits its role in general dental practice. Tetracycline may be considered as an alternative therapy for penicillin-allergic patients over the age of 13 who cannot tolerate erythromycin. Clindamycin is very effective against all odontogenic pathogens, but its potential gastrointestinal toxicity relegates it to third- or even fourth-line therapy in general dentistry. Although metronidazole displays excellent activity against anaerobic gram-negative bacilli, it is only moderately effective against facultative and anaerobic gram-positive cocci, and should not be used alone in the treatment of acute odontogenic infections.