Evaluation of A. actinomycetemcomitans and P. gingivalis from the mouth of patients irradiated in the head and neck region: a cross-sectional study

Purpose This study aimed to quantify Aggregatibacter actinomycetemcomitans (A.a) and Porphyromonas gingivalis (P.g) from the mouth of head and neck irradiated and cancer-free patients. Methods Information such as age, presence of tongue coating, salivary flow, and biofilm were collected from head and neck irradiated patients (Group 1) and compared the results with a group of cancer-free individuals (Group 2). The presence of tongue coating was clinically examined. Sialometry was performed through a stimulating technique by chewing paraffin. Microbiological samples were collected from buccal and labial mucosa and tongue dorsum. Subsequently, the samples were processed and analyzed by qPCR to detect the presence and quantify the bacteria. Results There was a statistical difference in the quantity of bacteria among the 24 individuals in Group 1 (A.a, 2817 +/- 8718; P.g, 3145 +/- 11297) and 26 individuals in Group 2 (A.a, 133996 +/- 398545; P.g, 60 +/- 195) regarding tongue coating (Group 1, A.a 2194.6 +/- 4641.5; Group 2, A.a 92767.8 +/- 333385.7) and salivary volume (Group 1, 0.69 mL; Group 2, 3.09 mL). The linear regression analysis found that the variable group was the main responsible for the difference in the quantity of periodontal pathogens (p-value < 0.001). There was no statistical difference in the amount of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis between totally edentulous and partially edentulous (with 12 or fewer teeth) patients. Conclusion Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were present in significant amounts in patients of both groups, with a greater quantity in cancer-free individuals.