Is 405cc going to look to big for my body?

The goal of breast augmentation is to optimally fill your breast envelope. Not to overstuff it, and not to understuff it! We utilize 5 measurements that help us find the right size for our patient and that also helps us give you a 24 hour recovery after your procedure. It's strange that you're picking sizes (especially that you yourself "downsized" from a 480 to 405 and now are thinking of going smaller) because your plastic surgeon should be the one to tell you the size that is best for you. I would suggest finding a board certified plastic surgeon who can spend the necessary time with you to properly examine and measure you so you know the optimal breast implant size for your body. Good luck!

Thank you for the question but, despite your good description of goals, online consultants will not be able to provide you with specific enough advice to be truly helpful. Ultimately, careful communication of your goals (in my practice I prefer the use of goal pictures, direct examination/communication in front of a full-length mirror, the use of in bra sizers, and computer imaging)  will be critical.
Generally speaking, the best online advice I can give to ladies who are considering  breast augmentation surgery ( regarding breast implant size/profile selection) is:
1. Concentrate on choosing your plastic surgeon carefully.  Concentrate on appropriate training, certification, and the ability of the plastic surgeon to achieve the results you are looking for. Ask to see lots of examples of his/her work.
2. Have a full discussion and communication regarding your desired goals  with your plastic surgeon. This communication will be critical in determining  breast implant size/type/profile will most likely help achieve your goals. 
In my practice, the use of photographs of “goal” pictures (and breasts that are too big or too small) is very helpful. I have found that the use of words such as  “natural” or "C or D cup” or "too big" etc means different things to different people and therefore prove unhelpful.
 Also, as you know, cup size varies depending on him who makes the bra; therefore, discussing desired cup  size may also be inaccurate.  Again, the use of computer imaging has been very helpful during the communication process, in our practice.
3.  Once you feel you have communicated your goals clearly,  allow your plastic surgeon to use his/her years of experience/judgment to choose the breast implant size/profile that will best meet your goals.  Again, in my practice, this decision is usually made during surgery,  after the use of temporary intraoperative sizers.
I hope this (and the attached link, dedicated to breast  augmentation surgery concerns) helps.

I consider
two factors when selecting implants for my patients:1. Dimensional planning2. Gel Implant Sizing systemDimensional
planning – The measurements of your chest wall are taken. Also, the
breast dimensions including the height, width, and current dimensions of
each breast form the basis of dimensional planning. Based on these
measurements, the implant size is recommended. This will give you a
unique breast implant that is suited for your body frame. However, there
are some limitations of what size we can recommend. For instance, some
implants may just be too big for a narrow chest wall. Your surgeon can
review this with you during the consultation.Gel Implant Sizing
system – During the preliminary breast implant consultation, you will be
provided with an option to “try on” a variety of implant shapes and
sizes. You can also visualize the possible outcomes of your surgery
which helps you to get that perfect size to give you the shape that you
longed for. This way your preferences are known and you can then pick a
range of implants that will “fit” just right to give a soft natural
fuller look. Hope this helps.Dr. BasuHouston, TX