This is a very controversial topic with no clear answer. To my knowledge there is not a definitive study or consensus on this topic. Here is the background information: Breast implants (and other implantable medical devices) are widely believed to increase a patient’s risk of infection or capsular contracture from bacteria entering the blood stream (oral bacteremia) and settling on the implant causing an infection or capsular contracture. As dental treatment bacteremia is a rare cause of metastatic infections it makes it difficult to attribute causality.
Some surgeons treat their patients with prophylactic oral antibiotics in the period directly after breast augmentation with breast implants as well as for any procedure that causes transient bacteria, such as dental surgery, colonoscopy, urological procedures (e.g. cystoscopy), and gynecological procedures. Probably a single dose, one hour prior to the treatment followed by single dose after the treatment should be sufficient, as long as the patient is not immunocompromised.
Whether this should be done for the first 6 months to 1 year after the breast implant placement is unclear at best. To my knowledge, there isn’t any compelling data to support this. Intuitively many surgeons treat breast implants like other implantable medical devices like pacemakers and total joint replacements.
Even vaguer is dental cleaning. One could argue that we cause a bacteremia when we simply brush our teeth and so dental cleaning is only a more aggressive cleaning. Some surgeon’s recommendations may differentiate between superficial dental cleaning (no antibiotics) and deep cleaning and periodontal treatment (antibiotics therapy). There have been anecdotal reports of infection and capsular contracture following dental treatment. Therefore some plastic surgeons and patients after considering the risk of 1–2 doses of antibiotics vs the unlikely but potentially irreparable problems with your implant is worth the risk. As there is no great answer to this controversy, my recommendation is to follow the advice of your plastic surgeon and or other members of your health care team.