Breast reconstruction using mammary implants is a routinely performed surgical procedure that gives good aesthetic results with a relatively simple operation for the patients. When an adjustable expander/prosthesis with remote dome is used for reconstruction, the device is filled through an injection dome connected to the implant through a filling tube. The injection dome is usually inserted into a subcutaneous pocket, either in the axillary area or, most frequently, in the lower lateral thoracic area. Sometimes, this location is not well tolerated by the patient because of pain or discomfort in the breast-thoracic area and can give problems related to the distance, which causes kinking of the filling tube. To avoid this inconvenience and because of frequent patient complaints, the authors decided 3 years ago to place the injection dome in a parasternal position and compare this location with the previously used lower lateral thoracic location. Two hundred sixty patients were divided into two groups (130 patients in each group) and evaluated. All patients underwent mammary reconstruction in the authors’ department using Becker adjustable implants. In all patients, the injection microdome was used. In group A, the injection microdome was positioned in the lower lateral thoracic area; in group B, the injection microdome was positioned in a parasternal area. Both groups were compared, considering different features such as pain, discomfort, ease of injection, pain during puncture, aesthetic appearance, risk of kinking, and risk of upside-down rotation of the dome. Average follow-up was 1.6 years. Statistical analysis was performed using Pearson’s chi-square test regarding the differences in frequency of two features—aesthetic appearance and pain during puncture—between the two groups. The comparisons regarding both aesthetic appearance and pain during puncture did show a significant difference between the two groups, with a value of p < 0.05 in both cases. In the present study, the results showed how the patients had less pain during puncture and a better aesthetic appearance when the microdome was located in the parasternal position instead of the lower lateral thoracic area. Advantages and disadvantages of the locations used are discussed in this article.