Individuals undergoing 0cosmetic dentistry treatment will need to take antibiotics at some stage. An antibiotic used prior to treatment can be an effective way to stop an infection. The infection can be caused by mitral valve prolapse, also caused by implants, a joint replacement, or a heart murmur  which can be caused by a roughened heart valve. When heart muscle starts getting infected by bacterias and becomes a colony for bacterias then the situation called Endocarditis arises. Inflammation of heart muscles causing deformation of the heart and can lead to a life threatening situation of the heart. Antibiotic prophylaxis was initially administered to patients to prevent bacterial endocarditis. 

Guidelines have been modified several times since 1955 when it was originally published by The American Heart Association. Antibiotic regime had been made simpler in each of these revisions to improve patient compliance and comfort. Another important factor considered in these revisions are that the bacteria's present in the human body eventually becomes resistant to any long term antibiotic therapy.  

In 1990 the antibiotic prophylaxis guidelines were updated and one of the latest updates was in 2006. While reviewing the guidelines related to dentistry be aware that the original decision to use antibiotics to prevent infection was based on the assumption that if antibiotics can effectively treat infection then they also should be able to prevent such infections. All studies to evaluate and raitfy this premise were carried out strictly in the laboratory and still the mechanism for effective prevention of endocarditis is yet to be known.

Most physicians and practitioners follow guidelines issued by AHA, but particular doctors may change the dosages and medicines depending on the condition of the patients and there is nothing unusual about it.

Antibiotic prophylaxis is RECOMMENDED for the following:

High-risk category

Prosthetic cardiac valves,including bioprosthetic and homograft valves
Previous bacterial endocarditis
Complex cyanotic congenital heart disease (e.g., single ventricle states, transposition of the great arteries, tetralogy of Fallot)
Surgically constructed systemic pulmonary shunts or conduits

Moderate-risk category

Most other congenital cardiac malformations (other than above and below)
Acquired valvar dysfunction (e.g., rheumatic heart disease)
Hypertrophic cardiomyopathy
Mitral valve prolapse with valvar regurgitation and/or thickened leaflets

Antibiotic prophylaxis is NOT RECOMMENDED for the following:

Negligible-risk category (no greater risk than the general population)

Isolated secundum atrial septal defect
Surgical repair of atrial septal defect, ventricular septal defect, or patent ductus arteriosus
Previous coronary artery bypass graft surgery
Mitral valve prolapse without valvar regurgitation
Physiologic, functional, or innocent heart murmurs
Previous Kawasaki disease without valvar dysfunction
Previous rheumatic fever without valvar dysfunction
Cardiac pacemakers (intravascular and epicardial) and implanted defibrillators

FOR HIGH & MODERATE RISK PATIENTS
Antibiotic prophylaxis is recommended for the following dental procedures:

Dental extractions
Periodontal procedures including surgery, scaling and root planing, probing, and recall maintenance
Dental implant placement and reimplantation of avulsed teeth
Endodontic (root canal) instrumentation or surgery only beyond the apex
Subgingival placement of antibiotic fibers or strips
Initial placement of orthodontic bands but not brackets
Intraligamentary local anesthetic injections
Prophylactic cleaning of teeth or implants where bleeding is anticipated

FOR HIGH & MODERATE RISK PATIENTS
Antibiotic prophylaxis is not recommended for the following dental procedures

Restorative dentistry (operative and prosthodontic) with or without retraction cord
Local anesthetic injections (nonintraligamentary)
Intracanal endodontic treatment; post placement and buildup
Placement of rubber dams, postoperative suture removal, taking of oral impressions, and fluoride treatments
Placement of removable prosthodontic or orthodontic appliances and orthodontic appliance adjustment
Taking of oral radiographs
Shedding of primary teeth