It is very common to have a wound opening at the base of the inverted T incision. Once this area has healed then any excessive scar can be excised and reclosed. Most of the time smaller problems heal just fine with conservative wound care management.
An additional point regarding the problem of healing a the T-junction was not answered; What will the scar be like? I am happy to report that in nearly every case no further surgery was needed. The central crease line scar contracts and is hidden by the fold of the breast. It is just a matter of time to allow for wound healing as discussed by others. Best wishes.
Congratulations on having undergone the breast reduction procedure. You are correct in that the T junction area can displays difficultly healing and open wounds are not uncommonly seen. These wounds go on to heal through a process of contraction where the tissues heal from the sides towards the center of the wound; this process usually takes several weeks to occur, depending on the size of the wound. Hopefully you will be seeing your plastic surgeon on a frequent basis; he/she will be in the best position to evaluate your progress. Occasionally, removal of unhealthy tissue (debridement) and/or removal of exposed sutures, may expedite the healing process.
Best wishes; hopefully, you will be very pleased with the longer-term outcome of the procedure performed.
First of all, make sure your surgeon keeps a close eye on the wound. You may benefit from antibiotics and you certainly need appropriate wound care, though this can often be performed by the patient. Resolution of the swelling alone will not heal the wound. Wound healing typically takes place through contraction of the wound. Basically, this means that once the wound bed is healthy and has pink/red granulation tissue in its base, the wound will shrink in from the sides. There is also new skin formation (epithelialization). However, as I mentioned, your care should be directed by your surgeon or a wound care specialist who your surgeon refers you to. Good luck.