Abscesses in the head and neck frequently have odontogenic sources. As bacterial pathogens and antibiotic resistance patterns may change over time and based on location, we describe the current common bacteria found in odontogenic abscesses, the prevalence of antibiotic resistance, and differences in each between pediatric and adult patients in Upstate New York. This is a retrospective review of patients who underwent drainage of odontogenic abscesses (n = 131) from 2002 to 2012 at an academic institution. The medical records were reviewed for results of abscess cultures, comorbidities, and drainage procedures. Polymicrobial sources were identified in 60.3% and monomicrobial in 33.6%. Overall, the most common bacteria were alpha hemolytic Streptococci (33.6%), Streptococcus milleri (32.1%), Prevotella (16.8%), and coagulase-negative Staphylococcus (14.5%). Candida and Morganella spp were more common in children than in adults. Overall, antibiotic resistance was observed in seven different pathogens. The most common antibiotic resistances were to clindamycin and erythromycin, which should be considered when deciding initial antibiotic therapy, especially in adult patients, who trended in this study toward having pathogens with higher rates of resistance.