The risk of infection increases; thus, the fear of infection increases. There are recommendations about prophylaxis from bacterial infection in particular because bacteria are present everywhere on the skin, mucosa, intraoral, or inside the body as normal flora. Different types of bacteria are present and can be classified into Gram +ve and Gram -ve, aerobic and anerobic based on the way of metabolism and structure
Different types of bacteria
The structure of Gram-positive and Gram-negative microscopic organisms is delineated in the chart below.
- The thickness of the peptidoglycan layer and the nearness or nonattendance of the external lipid film are the two fundamental variables that cause Gram-positive and Gram-negative living beings to have different visibility properties.
- Gram recolouring typically occurs due to the cell wall’s ability to hold the precious stone violet recolour utilized. This can then be observed under a light microscope.
- Gram-positive microscopic organisms have a thick peptidoglycan in the outer layer without an external lipid film. In contrast, Gram-negative microscopic organisms have a lean peptidoglycan layer with a lipid shell in the outer layer.
- When alluding to their structure instead of their recolouring properties, Gram-positive bacteria are called monoderm since they need an external lipid film. Gram-negative microbes have an external lipid film, which suggests they have a more diverse physical structure than Gram-positive microscopic organisms.
Adverse effects of antibiotics
An increasing number of new antibiotics are periodically created to fight bacterial infections, so awareness of the adverse effects of antibiotics has started to increase at public and academic levels. Those effects include, but are not limited to, GIT disturbances such as nausea or vomiting, abdominal pain, loss of appetite, or allergic reactions.
Another point that should be considered is the development of antibiotic resistance due to the misuse of antibiotics.
The best online pharmacology course for dentists and dental students discusses different types of antibiotics, their side effects, and their uses in dentistry.
Risk benefit analysis
So, healthcare professionals should weigh the risks of antibiotic adverse effects against the potential impact of prophylactic antibiotics.
The National Institute of Clinical Excellence published its prophylactic guidelines against infective endocarditis for the first time in 2008. The guidelines discouraged the use of prophylactic antibiotics before invasive dental interventions; thus, most European countries followed the NICE guidelines and limited the use of prophylactic antibiotics.
As a result, the number of reported cases of infective endocarditis increased, as shown in Dayer’s study, which measured the incidence of infective endocarditis from 2000 to 2013.
courtesy of (Dayer et al., 2015)
On the other hand, Thornhill studied the number and nature of the adverse reactions and side effects of antimicrobials used as prophylaxis against infective endocarditis during almost the same period.
courtesy of (Thornhill et al., 2015)
As noticed from the previous chart, the number of adverse reactions significantly decreased starting in August 2008 after the NICE guidelines were applied.
Unlike the NICE guidance (NICE guidance on prophylaxis against infective endocarditis, 2008)
the American heart association (Infective Endocarditis, 2022) published its guidelines in which they recommend and insist on using prophylactic antibiotics, and they justify that by the increased morbidity among infective endocarditis patients.
So, we can say that there are no magical solutions, and health care professionals, especially dentists, should use their judgments and do risk-benefit analyses for every single case, keeping in mind the difference between clinical guidelines and recommendations.
Antibiotic prophylaxis for healthy patients
There are very few indications for prophylactic antibiotic prescription in regular healthy patients. However, antibiotic prophylaxis is often prescribed after invasive dental procedures to prevent superimposed infections and further complications.
The most common procedure that requires antibiotic prophylaxis is dental implants.
Several systematic reviews have proven that antibiotics reduce the risk of failure with dental implants. If you want to learn more about dental implantology precautions, you can subscribe to the best online dental implant course.
Also, after surgical extraction of wisdom teeth and to prevent infection of the maxillary sinus after harrowing extraction and the presence of oroantral communication
Periodontal surgeries, bone grafts, soft tissue grafts, and gingival grafts are invasive procedures requiring antibiotic prophylaxis. These procedures are sensitive and highly need antibiotics.
However, clinicians should not routinely use prophylactic antibiotics before or after every intervention for healthy regular patients, as this will increase the number of adverse drug reactions and bacterial resistance among the population.
Antibiotic prophylaxis for medically compromised patients
Prophylactic regimens for medically compromised patients show the medical conditions and procedures for which GDPs might consider prescribing prophylactic antibiotics.
Only a minority of dental practitioners believed that a history of diabetes, hemodialysis, Hodgkin’s disease and AIDS, immunosuppressive therapy, autoimmune disorders and renal transplant were an indication for prophylactic antibiotics. Except for diabetes, the majority of respondents felt they would seek specialist advice for other conditions.
The response to cardiac conditions, apart from patients with aortic stenosis and ventricular septal defects, was that most practitioners would give antibiotics for extractions, restorations involving the gingival margin, scaling and polishing but not impressions.
Coronary heart disease and bypasses, pacemakers and physiological murmurs were not generally seen as an indication for prophylactic antibiotic cover. Approximately 25% felt that a history of prosthetic joints was an indication for prophylactic cover, with approximately 40% of GDPs covering patients with a history of rheumatic fever with no valvular dysfunction when carrying out scaling, polishing, and extractions. Only 21.8% felt there was a need to provide antibiotic prophylaxis for extractions on patients who had undergone radiotherapy to the head and neck.
Antibiotics should never be a substitute for good surgical and aseptic operating techniques. Amoxicillin was the most prescribed antimicrobial for these procedures.
This is a logical choice as it attains high serum concentrations and is effective against facultative and some anaerobic flora that may cause post-operative infection.
Penicillin was the next most popular prophylactic antibiotic, but resistance by both the oral facultative and anaerobic bacteria lessens its usefulness. Prophylactic metronidazole is also appropriate, as anaerobes are usually involved in post-operative infection.
Prosthetic joints
A panel of experts convened by the American Dental Association Council on Scientific Affairs developed an evidence-based clinical practice guideline (CPG) on using prophylactic antibiotics in patients with prosthetic joints undergoing dental procedures.
This CPG clarifies the “Prevention of Orthopedic Implant Infection in Patients Undergoing Dental Procedures: Evidence-based Guideline and Evidence Report,” developed and published by the American Academy of Orthopedic Surgeons and the American Dental Association.
The 2014 Panel made the following clinical recommendation: Prophylactic antibiotics are not recommended before dental procedures to prevent prosthetic joint infection for patients with prosthetic joint implants. The practitioner and patient should consider possible clinical circumstances that may suggest the presence of a significant medical risk in providing dental care without antibiotic prophylaxis, as well as the known risks of frequent or widespread antibiotic use.
As part of the evidence-based approach to care, this clinical recommendation should be integrated with the practitioner’s professional judgment and the patient’s needs and preferences.
NICE guidelines and AHA guidelines
Antibiotics aren’t necessary for everyone with heart disease who wants to avoid infective endocarditis (IE). Heart illnesses are categorized as having a high, medium, or low risk of developing IE. Those with a high risk of infection must have IE prophylaxis before endoscopies and urinary tract procedures.
There are a number of diseases that are considered to be high-risk:
- Unrepaired cyanotic congenital heart illnesses
- Congenital heart disease that was completely repaired within the first six months
- Artificial heart valves
- Congenital cardiac defects that have not been fully corrected
- Valvopathy after a heart transplant
- ِA history of infective endocarditis
- Hypertrophic cardiomyopathy
- Developed valvular heart disease with stenosis or regurgitation
The American Heart Association recommends the following antibiotic regimens for antibiotic prophylaxis:
One hour before the surgery, take amoxicillin by mouth and ampicillin intravenously or intramuscularly. Patients who are allergic to penicillin are advised to take azithromycin, clarithromycin, or clindamycin orally one hour before the procedure.
In the United Kingdom (NICE guidance on prophylaxis against infective endocarditis, 2008)
NICE clinical recommendations no longer recommend prophylaxis because there is no evidence that it reduces the incidence of IE, and the risks of taking antibiotics (allergy and increased bacterial resistance, for example) may exceed the benefits.
Antibiotics were once regularly used to prevent IE in those with heart problems and had dental work done (dental antibiotic prophylaxis). However, there isn’t enough evidence to say whether antibiotics are beneficial or useless at preventing IE when given before dental treatments in people who are at high risk. For this treatment, they are less frequently indicated.
Prior to dental treatments, high-risk individuals may be given prophylactic antibiotics such as penicillin or clindamycin for penicillin-allergic people in some countries, such as the United States. Bacteriostatic rather than bactericidal prophylactics should be used.
Due to concerns about antibiotic resistance, such steps are not adopted in some nations, such as Scotland. Antibiotics such as penicillin and amoxicillin (for beta-lactamase-producing bacteria) are used in prophylaxis since bacteria are the most common cause of infective endocarditis.
Furthermore, Healthcare providers should provide clear and consistent information on prevention to people at high risk of infective endocarditis, including:
- The significance of proper dental hygiene
- Signs and symptoms of infective endocarditis, and when to seek medical help
- The dangers of invasive procedures, such as body piercing and tattooing, which are not medical
- Antibiotic prophylaxis for infective endocarditis is not generally recommended for:
- For people who are having dental work done
- For those who are having non-dental procedures performed at the following locations
- Gastrointestinal tract (upper and lower)
- Medical operations involving the genitourinary tract, including urological, gynecological, and obstetric procedures
- Procedures for the upper and lower respiratory tract, including bronchoscopy and ear, nose, and throat procedures
People at risk of infective endocarditis who are having dental treatments should not be given chlorhexidine mouthwash as a preventive against infective endocarditis.