The surgeries in the middle third of the face that distort the anatomic and topographic integrity of the oral cavity, the nose and the sinuses, besides functional damage to these regions, also induce changes in their microfloras of diverse hypothetical combinations. This was the reason to start an investigation on the qualitative and quantitative structure of the microfloras of these regions and their changes. The investigation included 35 patients using a postresection prosthesis. The material for bacteriologic and microbiologic analyses was obtained by single swab sampling from six different localizations, cultured on the blood, TKV, ECV, TYCS, SABOURAND and ENDO agar over 24-48 hours, in aerobic and anaerobic conditions. Species belonging to the pyogenic cocci family, enterobacteria, oral streptococci and fungal microflora were detected in both the oral and the postresection cavity. Frequency distribution and Spearman's range correlation coefficient (R = 0.961; SS = 17; 14.280) (p<0.01) reveal the microfloras of the two cavities were almost identical regarding the species/families of the isolated microorganisms.