Increase in cariogenic bacteria after initial periodontal therapy.

Area of Science:

• Oral microbiology
• Periodontology
• Cariology

Background:

• Periodontal therapy aims to reduce periopathogenic bacteria.
• A potential consequence is a shift towards cariogenic flora (e.g., Streptococcus mutans).
• Understanding this microbial shift is crucial for comprehensive oral health management.

Purpose of the Study:

• To test the hypothesis of an intra-oral shift from periopathogenic to cariogenic flora during periodontal therapy.
• To evaluate the impact of different periodontal treatment strategies on oral microbial composition.
• To assess the efficacy of antiseptic regimens in preventing the shift to cariogenic bacteria.

Main Methods:

• Seventy-one periodontitis patients received one of three treatments: non-intensive scaling/root planing (NC), full-mouth scaling/root planing (FRP), or full-mouth disinfection (FMD) with antiseptics (chlorhexidine [CHX], fluoride [F], or combination [CHX+F]).
• Bacterial samples were collected from plaque, saliva, and tongue at baseline and at 2, 4, and 8 months.
• Detection frequencies and proportions of Streptococcus mutans and periopathogens were analyzed.

Main Results:

• Periopathogens decreased across all treatment groups.
• Streptococcus mutans increased in NC and FRP groups, indicating a shift to cariogenic flora.
• Antiseptic treatments (F, CHX, CHX+F) effectively reduced or eliminated Streptococcus mutans, preventing the hypothesized shift.

Conclusions:

• Initial periodontal therapy can indeed induce a shift from periopathogenic to cariogenic oral flora.
• Full-mouth disinfection with specific antiseptics (especially chlorhexidine and fluoride combinations) is effective in preventing this shift.
• Caries prophylactic regimens are necessary in conjunction with periodontal therapy to maintain a healthy oral microbiome.