# Antibiotic Prophylaxis Practices for the Prevention of Infective Endocarditis Among Japanese Dentists: A Questionnaire Survey of Members of the Hyogo Dental Association

## TL;DR

Many Japanese dentists correctly identify dental procedures needing antibiotic prophylaxis for infective endocarditis, but they struggle with cardiac indications, timing, and proper dosing.

## Contribution

This study identifies significant gaps in Japanese dentists' adherence to IE prophylaxis guidelines, particularly in timing and duration of antibiotic use.

## Key findings

- Only 32.5% of dentists administered antibiotics within 1 hour before procedures, as recommended.
- Multi-day antibiotic regimens were frequently used despite guidelines advocating single-dose regimens.
- Dentists had high recognition of major procedural indications but poor understanding of Class I and IIa cardiac conditions.

## Abstract

What are the main findings?
Many Japanese dentists correctly recognized dental procedures requiring infective endocarditis (IE) prophylaxis, but substantial gaps remained in identifying cardiac indications, optimal timing, and recommended single-dose regimens.Only one-third of dentists administered antibiotics within 1 h before procedures, and prolonged multi-day regimens were common despite guideline recommendations for a single pre-procedural dose.

Many Japanese dentists correctly recognized dental procedures requiring infective endocarditis (IE) prophylaxis, but substantial gaps remained in identifying cardiac indications, optimal timing, and recommended single-dose regimens.

Only one-third of dentists administered antibiotics within 1 h before procedures, and prolonged multi-day regimens were common despite guideline recommendations for a single pre-procedural dose.

What are the implications of the main findings?
Targeted educational interventions are needed to improve dentists’ understanding of guideline-based indications, timing, and duration of IE prophylaxis.Strengthening collaboration between medical and dental professionals may enhance adherence to evidence-based IE prevention practices and reduce unnecessary antibiotic use.

Targeted educational interventions are needed to improve dentists’ understanding of guideline-based indications, timing, and duration of IE prophylaxis.

Strengthening collaboration between medical and dental professionals may enhance adherence to evidence-based IE prevention practices and reduce unnecessary antibiotic use.

Background/Objectives: International guidelines—including the 2017 Japanese Circulation Society—recommend antibiotic prophylaxis before invasive dental procedures only for patients with clearly defined cardiac conditions at increased risk of infective endocarditis (IE), primarily Class I or IIa. However, IE prevention is not systematically incorporated into Japanese dental education, and dentists’ understanding of these indications remains unclear. We assessed dentists’ knowledge of guideline-based cardiac and procedural indications for prophylaxis, as well as their clinical practices regarding timing, duration, and antibiotic selection. Methods: A self-administered questionnaire was mailed to 3109 members of the Hyogo Dental Association. The survey evaluated recognition of Class I and IIa cardiac indications, dental procedures requiring prophylaxis, and self-reported prophylactic practices. Respondents were grouped by years of practice (≤20 vs. ≥21 years). Results: Overall, 367 dentists responded (11.8%). Correct identification of Class I indications was high for prosthetic valves (83.4%) and previous IE (93.7%) but low for complex congenital heart disease (55.5%) and post-shunt surgery (52.0%). Recognition of Class IIa indications was limited (36.4–51.1%). Awareness of procedural indications was high for tooth extraction (92.9%) and periodontal surgery (84.3%) but low for subgingival scaling (47.6%) and root canal treatment (36.7%). Only 60.5% of dentists correctly understood that prophylaxis is indicated for a Class I/IIa cardiac condition and an invasive dental procedure. Furthermore, 32.5% of dentists administered antibiotics within 1 h before treatment, and single-dose regimens were uncommon (14.7%). Multi-day regimens were frequently used. Amoxicillin was the most commonly selected antibiotic (40.8%). No major differences were observed between the groups. Conclusions: Although dentists demonstrated good awareness of major procedural indications, substantial gaps remain in recognizing Class I and IIa cardiac indications and in adhering to guideline-recommended timing and duration. Targeted education and improved collaboration between medical and dental professionals are needed to promote evidence-based IE prevention and reduce unnecessary antibiotic use.