From the Research
The deep layer suture is typically larger than the suture used for the superficial layer in surgical wound closure. Deep sutures are generally made of absorbable materials like polyglactin (Vicryl) or polydioxanone (PDS) in sizes ranging from 2-0 to 3-0, while superficial sutures are usually smaller, ranging from 4-0 to 6-0, depending on the location 1. This size difference exists because deep sutures need to provide structural support and bear tension while approximating deeper tissue layers like fascia and muscle. The larger diameter offers greater tensile strength needed to hold these high-tension areas together during healing.
Some key points to consider when selecting suture sizes include:
- The smallest suture size that will accomplish the purpose should be chosen to minimize tissue trauma and foreign material within tissues 2
- Deep sutures should be made of absorbable materials to reduce the risk of chronic inflammation and suboptimal scarring 2
- Superficial sutures are primarily for cosmetic approximation of skin edges and require less tensile strength 1
Using appropriately sized sutures for each layer is crucial for optimal wound healing - too large a suture in superficial layers can cause unnecessary tissue trauma and scarring, while too small a suture in deep layers may break under tension, leading to wound dehiscence. A study comparing scar outcomes between single-layer deep-dermal suture technique and conventional layered suture technique found that at 12-month follow-up, the difference in scar outcome between the two techniques diminished, with scars for both sides appearing similar 3.
In terms of specific suture materials and sizes, one study recommends using 0,2-0 polydioxanone sutures (PDS II) for deep/superficial fascia sutures, 4-0 or 5-0 PDS II for dermal sutures, and 6-0 or 7-0 polypropylene or nylon sutures for superficial sutures 1. Ultimately, the choice of suture size and material will depend on the specific needs of the patient and the location of the wound.