Under-Muscle Breast Implant Surgery vs Over-Muscle Surgery

Before considering breast augmentation surgery, one of the important decisions you will face is the type of breast implant placement. The choice between under-muscle breast implant surgery and over-muscle surgery can influence the appearance, feel, and long-term results of your breast implants.

Understanding the differences between submuscular and subglandular placement can help you make an informed decision to achieve your desired results.

Breast Implant Placement Options

Breast implant placement refers to where breast implants are positioned relative to the natural breast tissue and chest muscles. The two main options are:

• Submuscular placement (under the pectoralis major muscle)
• Subglandular placement (over the chest muscle but under the breast tissue)

The decision depends on factors such as breast tissue thickness, the amount of breast tissue you have, skin thickness, implant size, and your desired natural-looking result.

Understanding Submuscular Placement

Submuscular placement, also called under-the-muscle placement, involves positioning the implants beneath the pectoralis major muscle. This muscle implant approach can provide additional soft tissue coverage, particularly for patients with very little breast tissue.

How Submuscular Implants Work

The pectoralis major muscle lies over the chest wall, covering the upper portion of the breast. During breast implant surgery, the surgeon creates a pocket beneath the pectoralis major muscle to place the implant.

This muscle breast approach allows the implant to be supported by both the natural breast tissue and the chest muscle, contributing to a smoother contour and potentially reducing the visibility of the implant edges.

Understanding Subglandular Placement

Subglandular placement, also known as over-the-muscle, positions the breast implants between the natural breast tissue and the pectoralis major muscle. This method relies primarily on the glandular tissue and soft tissue for implant support.

How Implants Over the Muscle Work

In subglandular implant placement, the surgical procedure involves creating a pocket above the chest muscle. The implant rests directly under the breast tissue, which can make the surgical technique slightly less invasive and the recovery period potentially shorter.

Comparing Under Muscle vs Over the Muscle

Choosing between under-muscle and over-muscle placement depends on several factors, including your breast tissue thickness, skin quality, and desired natural-looking result.

Here’s a closer look at how each option compares:

Tissue Coverage and Overall Appearance

The thickness of your breast tissue and skin is a key consideration when determining implant placement. Patients with minimal breast tissue might benefit from submuscular implants, as the pectoralis major muscle provides additional soft-tissue coverage.

Conversely, those with more breast tissue may achieve a natural appearance with subglandular placement, where the implant sits above the chest muscle but under the glandular tissue.

Skin and Soft Tissue Quality

The quality of your skin and soft tissue is another essential point of difference. Adequate tissue thickness can enhance the natural appearance of your breast implants, regardless of placement.

In cases with less breast tissue, submuscular placement can improve implant coverage and reduce the chance of visible edges.

Breast Implant Size

Your desired implant size can influence the choice between under-muscle and over-muscle placement.

Larger implants may require submuscular positioning for additional support and optimal contouring, while moderate or smaller implants may sit naturally in a subglandular pocket, provided sufficient breast tissue exists.

Recovery and Post-Operative Considerations

Muscle placement often involves the chest, which may result in temporary post-operative discomfort or tightness while the pectoral muscle contracts during daily movement.

In contrast, over the muscle placement typically allows a more comfortable initial recovery, as the muscle is not disturbed. Your board-certified medical practitioner will provide tailored advice to support your healing process and ensure a favourable outcome.

Achieving a Natural-Looking Appearance

Both submuscular and subglandular placements can deliver natural-looking results when the breast tissue thickness, skin coverage, and implant size are carefully considered.

During your consultation, your medical practitioner will assess your natural breast tissue and recommend the implant positioning that complements your body and aesthetic goals.

Types of Breast Implants

When considering breast augmentation, understanding the different types of breast implants is essential for choosing the option that complements your natural breast tissue and desired outcome.

Silicone Implants

Silicone implants are filled with a cohesive silicone gel that closely mimics the feel of natural tissue. They are widely used in both submuscular and subglandular placements, offering a smooth, soft contour that can enhance the natural appearance of your breasts.

Their structure provides reliable implant positioning and is particularly suitable for patients seeking a natural-looking result.

Saline Implants

Saline implants are filled with sterile saltwater, allowing adjustable volume during breast implant surgery. They are versatile and suitable for both under-the-muscle and over-the-muscle placement options.

Once in place, saline implants conform to the existing breast tissue, supporting a balanced implant positioning and natural contour.

Both silicone and saline implants can be effectively used in submuscular or subglandular placement, with your medical practitioner guiding the selection based on your breast tissue thickness, skin coverage, and aesthetic goals.

Potential Complications

While breast augmentation surgery is generally considered effective when performed by a board-certified medical practitioner, it is important to understand the potential risks and considerations associated with breast implant placement.

Being aware of these factors can help you make an informed decision and prepare for a smooth post-operative experience.

Capsular Contracture

One of the commonly discussed risks is capsular contracture, a condition in which the scar tissue surrounding the breast implant tightens. This may affect implant positioning and soft-tissue feel.

Research indicates that implants under the muscles may have a slightly lower risk compared to subglandular implants, though careful post-operative monitoring is essential for both placements.

Implant Malposition or Shifting

Occasionally, breast implants may move or shift from their intended position. Proper surgical technique, appropriate implant size, and consideration of breast tissue thickness are important factors in minimising this risk.

Your medical practitioner will advise on how to support optimal implant positioning during recovery.

Changes in Breast or Soft Tissue

Over time, changes in natural breast tissue, skin elasticity, or tissue thickness may affect the appearance of breast implants.

These changes are part of the natural ageing process and can influence the upper pole contour and implant visibility, particularly in patients with less breast tissue.

Sensory Changes

Temporary or, in rare cases, long-term changes in breast sensation may occur following breast implant surgery.

Sensory changes are generally more common with subglandular implants, although individual experiences vary.

Infection and Wound Healing

As with any surgical procedure, there is a small risk of infection or delayed wound healing.

Your board-certified medical practitioner will provide guidance on post-operative care to support healthy healing and reduce the risk of complications.

 

 

Frequently Asked Questions

Does placement affect implant longevity?

Placement can influence factors such as capsular contracture risk, but both submuscular and subglandular implants are long-lasting when monitored appropriately.

Does under-muscle placement hurt more?

Submuscular implants may cause temporary chest muscle discomfort during the early post-operative period due to manipulation of the pectoralis major.

Subglandular placement generally allows a smoother initial recovery, but both approaches are managed carefully by your medical practitioner.

Can I switch from over the muscle to under the muscle later?

Yes, in some cases, you may undergo a revision procedure to move subglandular implants to a submuscular position. This decision depends on existing breast tissue, implant size, and your medical practitioner’s assessment.

How does muscle activity affect submuscular implants?

When muscle breast implants are placed under the pectoralis major, chest muscle contractions may temporarily influence the implant position. This effect usually diminishes as healing progresses and the soft tissue adapts around the implant.

Can placement affect nipple sensation?

Temporary or mild changes in nipple sensation can occur with both placements. In some cases, subglandular placement may slightly increase the risk of altered sensation, but typically, changes are temporary.

Can breast implants affect breastfeeding?

Breast implants generally do not interfere with breastfeeding, particularly if the implant is placed away from the nipple and milk ducts. Both submuscular and subglandular placements can allow for successful breastfeeding, though your medical practitioner will provide personalised guidance.

Conclusion

Understanding the differences between implants placed under the muscle and those placed over the muscle can empower you to make informed decisions about breast augmentation.

Both submuscular and subglandular implants offer distinct benefits, and the optimal choice depends on your natural breast tissue, implant size, and overall breast augmentation goals.

Consulting a board-certified medical practitioner ensures your implant surgery is performed with careful attention to achieving a natural-looking result and long-term satisfaction.

Our board-certified medical practitioners are here to guide you through every step, from evaluating your existing breast tissue to discussing implant placement options that suit your body and goals.

Contact Refine Clinic at (02) 8599 7161 to receive personalised advice and discover which breast implant placement can help you achieve a balanced and natural appearance.

Disclaimer: Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner. 

References

Gallagher, G. (2020, June 12). Saline vs. Silicone Implants for Breast Augmentation. Healthline. Retrieved November 19, 2025, from https://www.healthline.com/health/saline-vs-silicone-implants

Griffin, R. M. (2024, June 5). Breast Implant Safety. WebMD. Retrieved November 19, 2025, from https://www.webmd.com/beauty/cm/breast-implant-safety

Haas, E., Christodoulou, N., Secanho, M., Kokosis, G., Malgor, R. D., Winocour, J., Yu, J. W., Mathes, D. W., & Kaoutzanis, C. (2025). Capsular Contracture After Breast Augmentation: A Systematic Review and Meta-Analysis. Aesthetic Surgery Journal Open Forum, 7, ojaf003. https://doi.org/10.1093/asjof/ojaf003

Healthdirect Australia. (2023, December). Breast Augmentation (Breast Implants). Healthdirect. Retrieved November 19, 2025, from https://www.healthdirect.gov.au/breast-augmentation-breast-implants