Commentary on: Does Implant Surface Texture Affect the Risk of Capsular Contracture in Subglandular Breast Augmentation and Breast Augmentation-Mastopexy?

In this article, the authors report the results of a single-practice, two-surgeon, retrospective chart review of the comparative incidence of capsular contracture when smooth or textured implants are utilized in the subglandular pocket for breast augmentation and breast augmentation-mastopexy.1 The impetus for this evaluation was based on the historical impression that the utilization of textured implants reduced the incidence of capsular contracture. Whereas it has been difficult to demonstrate a statistically significant difference in capsular contracture rates when implants are placed in the submuscular pocket, many previous studies have demonstrated a weak association between textured implants and lower capsular contracture rates when placed in the subglandular position.2-6 The proposition by the authors is that improved techniques to mitigate bacterial contamination, based on an emerging understanding of contamination as an etiology of capsular contracture, can lead to lower capsular contracture rates independent of the implant surface. In this review, 536 patients were identified for comparison: 212 received smooth implants and 314 received textured implants. With an average follow-up of 461 days for the smooth group and 756 days for the textured group, no statistically significant overall difference in risk of capsular contracture was found between the 2 groups. However, in interpreting the conclusions of this study, further evaluation and discussion are warranted. First, emerging evidence for bacterial exposure and formation of biofilm as contributing to the etiology of capsular contracture has provided a framework for reducing capsular contracture rates by minimizing bacterial contamination. The authors should be commended for performing breast augmentation and augmentation-mastopexy with such mastery and attention to detail and for accomplishing an impressively low capsular contracture rate of 1.61% for breast augmentation and 2.89% for augmentation-mastopexy. These low rates are especially impressive because the implants were placed in the subglandular position, which has historically been associated with much higher capsular contracture than submuscularly placed implants.2-6 The authors’ reported rates are significantly lower than much of the published data and represent the most significant conclusion of this article that adherence to specific techniques to minimize bacterial contamination, including the 14-point plan or a host of other techniques, likely plays the most important role in the effort to reduce capsular contracture.7 These low rates, however, do create a challenge when attempting to draw any significant conclusions from the study, especially with the relatively small sample size of 536 patients. Sample size does matter due to the fact that the lower the rate of a complication, the more robust the study population must be to discern statistically significant relationships. Thus, when only 5 capsular contractures were observed in the 314 texture patients and 7 in the 212 smooth implant patients, demonstrating statistical significance is challenging and requires a deeper look at trends in the data. For example, in the overall population there was a nonsignificant difference in capsular contracture rates between textured (1.59%) and smooth (3.3%) implants (P = 0.20). However, in the subset of patients in the breast augmentation cohort, the rate was 0% for textured implants compared with 3.2% for smooth implants, which was statistically significant (P = 0.05). Therefore, even with small cohorts and shorter follow-up time for smooth compared with textured implants, there was a favorable outcome with textured implants with a significantly lower capsular contracture rate. Even in the augmentation-mastopexy group, the same trend was evident; patients receiving textured implants had a 2.62% rate of capsular contracture compared with 3.45% for the smooth group (P = 0.70). An additional limitation is the fact that capsular contracture rates increase over time, as demonstrated in the FDA-mandated 10-year clinical trials.2,8 Therefore, the difference in duration of follow-up between the 2 groups must be factored into interpretation of these results. The smooth implant group had a much shorter mean follow-up interval of 461 days (range, 6-1884 days) compared with 756 days (range, 11-3063 days) for the textured implant group. It would be expected that as the mean follow-up time for the smooth implant group approaches the mean follow-up time for the textured group, more capsular contractures may emerge, increasing the trends already observed in higher rates of capsular contracture in the smooth implant group to a level of statistical significance. Additionally, the authors suggest that textured implants would inherently be expected to have higher capsular contracture rates because these devices are known to harbor more bacteria, the most significant contributor to capsular contracture based on the biofilm theory.7,9,10 At face value, this hypothesis would make sense. However, if that proposition were true, why are textured implants not associated with higher rates of capsular contracture in this study and the many other studies cited? One can argue whether texture lowers the capsular contracture rate, but minimal data are available to support a higher contracture rate with textured implants.2-5 It is true that textured surfaces are known to harbor 40 to 70 times the number of bacteria compared with smooth surfaces.11 To reconcile these findings, at a minimum, it appears that textured surfaces have some sort of “threshold” for bacterial burden, which allows a textured device to be exposed to more bacteria and yet not promote capsular contracture until this threshold is passed. Considering that logic, the authors’ experience in minimizing capsular contractures could lead to low rates for both smooth and textured devices as long as good techniques are employed. However, when techniques to minimize bacterial contamination are not employed, textured implants might actually be able to tolerate more contamination and still maintain lower capsular contracture rates compared with smooth implants. Further, it has been proposed that the subglandular pocket exposes more of the implant to contamination from the overlying breast parenchyma, thus leading to higher rates of capsular contracture and providing further evidence of the impact of excellent surgical technique and the benefits of textured surfaces. Finally, the authors should be congratulated for defining a process for breast augmentation that through meticulous preoperative preparation and operative management mitigates bacterial contamination and achieves impressively low capsular contracture rates, regardless of implant surface. I concur with the authors in regard to the many advantages of placing an implant above the muscle, such as the avoidance of animation deformities, enhanced ability to create cleavage, and avoidance of weakening of the shoulder joint. Because capsular contracture has been one of the major risks of subglandular placement, the low contracture rates reported in this study, even when placing an implant in the subglandular pocket, provide renewed confidence in the utilization of the subglandular pocket when advantageous. However, I do not believe the authors’ data demonstrate equivalence between smooth and textured devices when placed in the subglandular pocket. As noted, smooth devices in the breast augmentation cohort actually had a significantly higher rate of contracture compared with textured devices. There is a real possibility, as more time passes and the follow-up times equalize, that greater differences between device types may come to light. It does appear that textured devices have some ability to harbor greater amounts of bacteria and yet not increase—and potentially even decrease—the incidence of capsular contracture. The potential impact on contracture rates may be even greater when a process of breast augmentation that mitigates bacterial contamination is not employed. However, in light of our current implant environment and concerns related to the use of textured devices, especially breast implant-associated anaplastic large cell lymphoma, this early report of low capsular contracture rates may provide some reassurance to surgeons in the utilization of the subglandular pocket with smooth devices. Of course, these results are predicated on the employment of meticulous techniques in the process of the breast augmentation. As always, when interpreting early results of any study, caution is advisable. This is especially true when analyzing capsular contracture, because the rate of contracture is known to continue to increase over time. I encourage the authors to continue this very important evaluation, because time will provide greater understanding and more confidence in the conclusions drawn in this study and an improved framework for achieving comparable outcomes no matter the implant surface or implant pocket selected. The author has lectured for and is a part of the medical advisory board for Sientra. The author received no financial support for the research, authorship, and publication of this article.