Introduction: Odontogenic infections are the most commonly encountered orofacial infections, which may spread into the adjacent anatomical spaces along the contiguous fascial planes, leading to involvement of multiple spaces which can progress to life-threatening situations.
Materials and methods: A prospective study was carried out on 100 consecutive cases of odontogenic infections treated at our institute over a period of 18 months by surgical intervention and intravenous antibiotics. Morphologic study of the isolates and antibiotic sensitivity testing was performed.
Results: Caries was the most frequent dental disease (53.27%), and the mandibular first molar was the most frequently involved tooth (41.9%) associated with the etiology of odontogenic infections. A total of 158 spaces were involved in 100 patients. In subjects with single space odontogenic infections (n = 61), submandibular space was most commonly affected (44.26%) followed by buccal space (27%). In subjects with multiple space infections (n = 39), submandibular space (30.19%) was most frequently involved followed by buccal space (17.92%). In the aerobic group/microaerophilic group, 17 different species were isolated in a total of 102 aerobic isolates. A total of 18 species were identified in 65 anaerobic isolates sampled.
Conclusion: Amoxicillin possess antimicrobial activity against major pathogens in orofacial odontogenic infections, but β-lactamase production has restricted the effectiveness of amoxicillin against the resistant strains of Staphylococcus aureus, Bacteroides, Prevotella and Porphyromonas. For the management of orofacial infections, the use of amoxicillin/clavulanate and clindamycin is recommended because of stability against β-lactamases.
Keywords: Antibiotic sensitivity; Drug resistance; Fascial spaces; Odontogenic infection.