Impact of oral surgery, with or without amoxicillin, on the oral microbiome, salivary flow and buffering capacity of saliva

In the post-operative period due to tooth extraction operations, antibiotic prophylaxis is not usually recommended. However in more traditional clinical practices the use of amoxicillin continues to represent the most effective factor in preventing bacterial infections. In order to evaluate the effectiveness of such an approach in the dental field, a phase IV, randomized, controlled, single-center double-blind clinical study was conducted, according to the split-mouth design. The investigation concerned only simple tooth extraction operations, in which patients were divided into two groups. Only one of the established groups was prescribed antibiotic therapy. The evolution of the oral microbiome was thus evaluated, through the count of Streptococcus mutans and Lactobacillus, the salivary flow and the buffering power of the saliva before and after the extraction procedure. In the antibiotic-treated group, several units reported a significant change in bacterial load, from baseline to seven days and fourteen days after surgery. In the same group, however, no significant changes occurred in the salivary flow and in the buffering capacity of the saliva. Given the high complexity of the salivary microbiome and its barrier functions for the human organism against attacks by pathogenic microbes, it is considered necessary to promote further studies aimed at investigating the mutations induced by antibiotic therapy, even if the results emerging from the most recent literature highlights the preventative role of prophylaxis in post-extraction complications. However, given the low incidence of infections even in the absence of prophylaxis, it becomes crucial to investigate how the risks of potential antibiotic resistance can compromise the benefits deriving from antibiotic use.