# A Review of Guidelines for Antibiotic Prophylaxis before Invasive Dental Treatments
## 2 Materials and Methods  
### Review of Guidelines  
1.1 Guidelines for Antibiotic Prophylaxis for Minimising the Risk of Infective Endocarditis in Cardiac Patients Receiving Invasive Dental Treatment  
Depending on the practitioner's global location, local guidelines differ. In the United Kingdom, the National Institute for Health and Care Excellence (NICE) in 2008 published Clinical Guideline 64 (CG64), recommending not to prescribe antibiotics prior to dental treatment. Recommendation 1.1.3 suggested that \"antibiotic prophylaxis is not recommended for people undergoing dental procedures\" [13]. Following the introduction of these guidelines, a significant decrease in antibiotic prescription and a surge in infective endocarditis uses were reported in 2015 (Table 2) [14]. Similarly, in the United States, it was revealed that antibiotic prophylaxis prescription was significantly decreased in both moderate- and high-risk individuals even though this decrease was not complying with American Heart Association (AHA) guidelines [15]. Furthermore, a Canadian study also revealed that a significant reduction in antibiotic prophylaxis prescription in moderate-risk patients and a minor change in individuals of high risk were evident [16]. In 2016, NICE reviewed their guidelines by recommending that \"antibiotic prophylaxis is not recommended routinely for people undergoing dental procedures\" [13]. However, the definition of which patients should be considered for \"nonroutine\" dental procedures and what is the appropriate antibiotic regimen(s) for use in dental management was not explained in these amended NICE guidelines, leading to confusion among UK dentists. To address this challenging problem, the Scottish Dental Clinical Effectiveness Programme (SDCEP) [8] developed an implementation advice to enable practice of the NICE guidelines. The NICE recommendation 1.1.1 lists which heart conditions are considered to be at an increased risk of developing infective endocarditis (Table 3). The SDCEP explained that the majority of these high-risk patients undergoing \"routine\" dental procedures will not require antibiotic prophylaxis and further included a subgroup of high-risk patients requiring special consideration and antibiotic prophylaxis for \"nonroutine\" dental treatments (Table 3). \begin{table}
\begin{tabular}{c c c} \hline \hline
**Country** & **Incidence before Guidelines** & **Incidence after Guidelines** \\ \hline United States of America [17] & 11–12 per 100,000 & 14–15 per 100,000 \\ Europe [18] & 33 per 1,000,000 & 32 per 1,000,000 \\ United Kingdom [19] & 22.2–41.3 per 1,000,000 & 42–67.7 per 1,000,000 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Incidence of infective endocarditis. \begin{table}
\begin{tabular}{c c} \hline \hline
**Conditions** \\ \hline
1. & Stenosis or regurgitation of heart valves \\
2. & Cardiomyopathy “hypertrophic” \\
3. & History of infective endocarditis \\
4. & Surgically corrected congenital heart disease or \\ National Institute for Health and & palliated structural conditions, but not including \\ Care Excellence (NICE) [13] & defects of the septal artery, fully repaired ventricular \\  & septal defect or patent ductus arteriosus which is fully \\  & repaired and endothelialised closure devices \\
5. & Restoration of a valve \\ \hline \hline \end{tabular}
\end{table} 
Table 3: High-risk patients for developing infective endocarditis. On the contrary, the American Heart Association (AHA), European Society of Cardiology (ESC) and, most recently, the Belgian Health Care Knowledge Centre (KCE) report 332 [21] recommend that prescription of antibiotic prophylaxis to minimise the possibility of developing infective endocarditis is reasonable before any dental procedure involving the handling of the gingiva as well as the periapical region of teeth and in cases of perforation of the oral mucosa in all patients with a high risk of developing infective endocarditis [6; 20; 21; 22] rather than just a subgroup of high-risk patients as indicated by the SDCEP.