Sir, I would be grateful if you could enlighten me on a topic that is causing me great concern. I encountered a patient recently who is 31 years of age. She is a single mother with four children. She has been to the dentist throughout her life for dental treatment. In the past she has had 11 adult teeth and numerous primary teeth extracted at different times. She has had countless scalings and root planings with conscientious dental practitioners following periodontal assessments with a periodontal probe. These episodes have taken place at different times from childhood to date. At present she has active decay in at least four teeth and she suffers from generalised chronic adult periodontitis. Her oral hygiene is poor and tooth brushing leads to profuse gingival bleeding.

Recently, after the birth of her fourth child she suffered a stroke. Further investigation revealed that she had a patent foramen ovale of which she had no prior knowledge. The recent guidelines indicate that a patent foramen ovale is a moderate risk factor for bacterial infective endocarditis.1 A patent foramen ovale can cause severe turbulence of blood flow causing damage to the endothelium which in turn increases the likelihood of forming a thrombotic vegetation. Bacteraemia from a dental procedure may lead to seeding of the vegetation and thus symptoms of infective endocarditis. As a moderate risk factor for causing IE, dental procedures such as extractions, sub gingival debridement, scale and polish, and periodontal probing all require antibiotic prophylaxis according to recommendations from groups such as Medical Practice Committee of the British Cardiac Society, the Faculty of Dental Surgery of the Royal College of Surgeons of England, the Society of Cardiothoracic Surgeons, and the Working Party of the British Society for Antimicrobial Chemotherapy.1,2,3

The fact that this patient had a patent foramen ovale was not known to anyone and only came to light after she suffered the stroke, as mentioned above. Therefore, no antibiotic prophylaxis was given to her for any of her at risk dental treatment procedures at any time throughout her life. However, she suffered no ill health at any time after her dental treatments throughout her life. Similarly there have been incidences where patients receive antibiotic cover for congenital heart conditions during dental procedures but still suffer from infective endocarditis.4

This has caused me to speculate whether antibiotic prophylaxis is necessary for this congenital heart condition and similarly perhaps some other congenital heart conditions. Had her relevant medical history been known she would have received numerous doses of antibiotic prophylaxis. I wonder if my experience is coincidental or have my learned colleagues had similar experiences? By giving antibiotic prophylaxis where there is no need are we increasing the likelihood of antibiotic resistance? It begs me to ask the question, am I doing the best for my patients by giving prophylaxis for such congenital heart conditions or do the guidelines need to be re-evaluated? In this evidence based medicine era are we practising evidence based dentistry?