Microbiology of facial cellulitis related to dental infection

The study objective was to identify bacteria responsible for facial cellulitis of dental origin.

Adult patients, admitted for facial cellulitis of dental origin were included. The pus sample was taken by swabbing during the surgical incision and drainage performed under general anesthesia. The bacteriological diagnosis was performed by microscopic examination and bacterial culture in aerobic and anaerobic atmosphere.

Two hundred and seven bacterial species were isolated from 100 samplings, that is to say 2.07 bacterial species per sample. 19% of the samples contained only aerobic germs, 36% only anaerobic ones, and 45% contained mixed aerobic and anaerobic flora. Streptococcus (65.38%) and Capnocytophaga (11.54%) were the most frequently isolated aerobic bacteria. The anaerobic bacteria accounted for 62.32% of isolates and the most frequently isolated were Prevotella (55%) and Fusobacterium (16.28%). Bacterial species were not significantly different according to the age (P-value=0.06) and sex (P-value=0.584). There was a significant statistical association between aerobic or anaerobic bacteria and clinical symptoms such as cheek edema (P-value=0.03) and pus at tooth root (P-value=0.02). Patients previously treated by antibiotic therapy presented significantly more infections due to the same respiratory germ type (P-value=0.009).

Even though the bacterial flora responsible for facial cellulitis of dental origin is polymorphic, anaerobic bacteria were predominant.