Interrelationship of capsule thickness and breast hardness confirmed by a new measurement method.

All implants initiate a foreign-body response that leads to their encapsulation by scar tissue. In order to better understand this encapsulation process and the differences between soft (comfortable) and firm (contracted) breasts, we studied 22 patients who had come in for reaugmentation during a 2-year period. The capsules removed were prepared and measured using a new method. The capsules were (1) removed and stored in physiologic solution until the time of measurement (30 minutes to 2 hours) and (2) measured using a Mitutoyo dial-thickness gauge (MDTG) that employs a uniform pressure of 85 gm. The measurements revealed that soft breasts (Baker 1) have the thinnest scar-tissue capsules, which ranged in thickness from 0.002 to 0.010 inches. Firm breasts yielded the thickest capsules. Baker 3 measured between 0.010 and 0.078 inches thick, and Baker 4 measured between 0.018 and 0.162 inches thick. We also compared the precision of measurement between the MDTG and a standard (screw-type) micrometer by taking a series of readings on a soft, pliable substance (textured silicone rubber).