Suture Materials

1. Dr.S.Harsha Vardhan

2.  Sutures, commonly called stitches, are sterile,
surgical threads that are used to repair cuts
(lacerations). They also are used to close
incisions from surgery.
 There are many kinds of sutures, with different
properties suitable for various uses.

3.  Causes minimal tissue injury or tissue reaction
( nonelectrolytic, noncapillary, nonallergenic,
noncarcinogenic)
 Easy to handle
 Holds securely when knotted (no fraying or cutting)
 High tensile strength
 Favorable absorption profile
 Resistant to infection
 Can be used in any tissue
 Good knot security

4.  Sutures must be strong (so they do not break),
non-toxic and hypoallergenic (to avoid adverse
reactions in the body), and flexible (so they can be
tied and knotted easily).
 In addition, sutures must lack the so called "wick
effect", which means that sutures must not allow
fluids to penetrate the body through them from
outside, which could easily cause infections.

5.  Sutures can be classified into two
groups: absorbable sutures and non-absorbable
sutures.
 An absorbable suture breaks down in tissue after
a given period of time. It degrades as a wound or
incision heals.
 A non-absorbable suture resists the body's
attempt to dissolve it. Non-absorbable sutures
may be removed by a surgeon after a surface
incision has healed.

6.  Absorbable sutures include :- Polyglycolic
Acid sutures, Polyglactin 910 , Catgut,
Poliglecaprone 25 and Polydioxanone
sutures.
 Non-Absorbable sutures include :-
Polypropylene sutures, Nylon (poylamide),
Polyester, PVDF, silk and stainless steel
sutures.

7.  Sutures can also be divided into two types on the
basis of material structure i.e. monofilament
sutures and multifilament or braided sutures.
 Braided sutures provide better knot security
whereas monofilament sutures provide better
passage through tissues.

8.  In general, Monofilament sutures elicit lower
tissue reaction compared to braided sutures.
 Multifilament sutures are braided and often coated
with various materials like silicon, wax, PTFE,
polycaprolactone, calcium stearate etc.

9.  Monofilament sutures include :-
Polypropylene sutures, Catgut, Nylon,
PVDF, Stainless steel, Poliglecaprone and
Polydioxanone sutures.
 Multifilament or braided sutures include :-
PGA sutures, Polyglactin 910, silk and
polyester sutures.

11.  Surgical sutures can also be divided into two
types on the basis of raw material origin i.e.
natural and synthetic sutures.
 Natural sutures include silk and catgut
sutures whereas all other sutures are
synthetic in nature.

12.  Some types of sutures are available with specialized
coatings on the surface to enhance properties like knotting,
easy passage through tissue and reduce tissue reaction.
 Normally, coating is applied to braided sutures rather than
monofilament sutures.
 It is easier to coat braided sutures compared to
monofilaments.
 Coating materials like chromium salt, silicon, wax, PTFE,
polycaprolactone, calcium stearate.

13.  Polymeric coating materials are known to be more
bio-compatible than conventional coating
materials like chromium salts, beeswax, pafaffin,
gelatin etc.
 There are new functional coatings like
antibacterial or antimicrobial coating given to both
monofilament and multifilament sutures, stem cell
coating for improving healing properties.

14.  Coated sutures include :- PGA sutures,
Catgut Chromic, Polyglactin 910, silk and
polyester sutures, braided or twisted
nylon, Poliglecaprone and Polydioxanone
sutures.
 Un-coated sutures include :-
Monofilament Polypropylene sutures,
monofilament Nylon, PVDF, Stainless
steel.

17.  Catgut or gut suture is an absorbable suture usually
manufactured from the intestine of sheep or goat.
 Catgut suture are composed of highly purified
connective tissue derived from either beef or sheep
intestines.
 The membrane is chemically treated and slender
strands are woven together to form a suture.
 The grinding process creates a strand of uniform
diameter.

18.  Plain catgut is usually having shorter absorption
periods and is absorbed more rapidly in infected
areas.
 The percentage of collagen in the catgut suture
often determines the quality of the suture.
 Higher percentages of collagen allow for: superior
tensile strength, longer absorption times, and
lower reactions in vivo.
 Plain catgut is available in ivory colour.

19.  Chromic catgut is treated with chromium salt
solution to resist body enzymes and slower the
absorption process thus supporting the wound for
longer periods.
 Chromic gut is chromicised before it is spun into
strands. This allows control over the amount of
chromic content for an even absorption rate.

20.  The chromic content not only increases the tensile
strength, but also reduces tissue irritation.
 Catgut sutures are sterilized by a sterilizing fluid
containing EO, distilled water and isopropyl
alcohol.

21.  Absorption within 75-90 days for chromic suture
and 60-70 days for plain gut suture.
 Allows for smooth passage through tissue.
 Uniform chrome content provides required wound
support and absorption.

22.  Stainless steel sutures are the most inert among all
suture materials and provide maximum tensile
strength.
 Stainless steel sutures are indicated for use in
abdominal wound closure, intestinal anastomosis,
hernia repair, sternal closure and also for certain
orthopedic procedures (cerclage or tendon repair).
 The steel suture is very malleable even with high
tensile strength and is resistant to breakage during
knotting.
 The suture merges with the contours of the bone.

23.  Steel suture is a non-absorbable suture.
 Sturdy yet soft to have a better knotting and
turning without breakages.
 Rust proof and stays in the body life long.

24.  Black braided silk suture is a multifilament braided
non-absorbable, sterile surgical suture which is
available only in black colour.
 Surgical silk begins as a filament of natural silk; it
is composed of approximately 70% protein fibers
& 30% extraneous material or gum.

25.  Silk suture is a non-absorbable suture.
 Braided to improvise the knot security.
 Coloured black to have a very good visibility
during surgical procedures.
 Coated with bee wax for easy pull out suture.
 Easy pull out sutures.
 As it a natural material it is very slowly absorbed
in the body over a period of 2 years hence
removal is not required from the endodermis.

26.  Polypropylene suture is a non-absorbable, sterile
surgical suture composed of an isotactic
crystalline stereoisomer of polypropylene or
synthetic linear polyolefin.
 As it is a monofilament suture, it does not support
bacterial growth. It is not affected by blood, or
weakened by tissue enzymes.
 It offers prolonged tensile strength even in
infected areas as it is not degraded over time.

27.  This suture is known for low tissue drag, easy
handling and good strength.
 Polypropylene suture are normallyavailable in blue
colour, allowing for easy identification and better
visibility against skin when operating.

28.  Polypropylene suture is a non-absorbable
 Smooth texture, resulting in minimal tissue
trauma.
 High plasticity and difficulty of use compared to
standard nylon suture.
 Uniform diameter with high tensile strength resists
breakage
 Highly visible in the wound
 Passes through tissue easily

29.  Polyamide suture is a monofilament non-absorbable,
sterile surgical suture composed is a macromolecule
with repeating units linked by amide bonds.
 Polyamide suture fibres are tough,possessing high
tensile strength, as well as elasticity and lustre.
 They are wrinkle-proof and highly resistant to abrasion
and chemicals such as acids and alkalis.

30.  As it is a monofilament suture, it does not support
bacterial growth. It is not affected by blood, or
weakened by tissue enzymes.
 It offers prolonged tensile strength even in
infected areas as it is not degraded over time.
 This suture is known for low tissue drag,easy
handling, lesser memory and good strength.

31.  Polyamide suture is a non-absorbable
 Smooth texture, resulting in minimal tissue trauma.
 Lesser plasticity and easier of use compared to
polypropylene suture.
 Uniform diameter with high tensile strength, resists
breakage.
 Available in black colour and is highly visible in the wound.
 Passes through tissue easily.

32.  Polyester suture is a multifilament braided non-
absorbable, sterile surgical suture which is
available in green and white.
 Polyester is a category of polymers which contain
the ester functional group in their main chain.

33.  Polyester suture is a non-absorbable suture.
 Braided to improvise the knot security.
 Coloured green and white to differentiate between layers
of knotting and differentiate b/w a stay and permanent
suture.
 High tensile strength
 Coated with silicone.

34.  Nylon was the first synthetic suture available, and
it is the most commonly used nonabsorbable
material in wound closure.
 It is available in both monofilamentous and
braided forms.
 Nylon has a high tensile strength, and,although it
is classified as nonabsorbable, it loses tensile
strength when buried in tissue.

35.  Braided forms retain no tensile strength after
being in tissue for 6 months,whereas
monofilamentous forms retain as much as two
thirds of their original strength after 11 years.
 Monofilament nylon is stiff; therefore, handling and
tying are difficult and knot security is low. The
suture also may cut easily through thin tissue.

36.  Braided forms have better handling properties but
greater tissue reactivity and cost.
 They are used infrequently in wound closure.
 Monofilament nylon is relatively inexpensive and
available as black, green, or clear.
 Although its greatest use is as a percutaneous suture,
because of its low tissue reactivity, nylon (clear) can
be used as a buried suture in situations in which
prolonged dermal support is necessary.

37.  Polyglactin 910 or PGLA suture is an absorbable,
sterile, synthetic, braided suture. PGLA suture are
indicated for soft tissue approximation and
ligation.
 The suture’s tensile strength remains for
approximately three to four weeks in tissue.

38.  Polyglactin 910 suture is an absorbable braided
synthetic fibre. It is available as a plain (uncoated) and
coated suture.
 The coating is with calcium stearate. This mixture
forms an absorbable, adherent, non-flaking lubricant
ideal for suture.
 These components are water repelling which slows
tissue fluid penetration and absorption into the suture.

39.  Clinical trials have shown that after two weeks,
approximately 70% of Polyglactin 910 suture’s
initial strength remained.
 Polyglactin suture are found to be non-antigenic
and non-pyrogenic, eliciting only mild tissue
reactivity during the absorption process.
 Polyglactin 910 suture are available violet and
colourless.

40.  Polyglactin 910 suture is coated in order to create a smoother synthetic
absorbable suture that will pass through tissue readily.
 Easy tissue passage
 Precise knot placement as compared with PGA suture
 Predictable absorption by simple hydrolytic mechanism
 A decreased tendency to irritate tissue
 Greater tensile strength
 A longer absorption period

41.  PGA is an ideal and time tested synthetic
absorbable suture, widely used by surgeons all
over the world.
 PGA's superior features over catgut are
predictable absorption, outstanding tensile
strength, in-vivo inertness and excellent handling
properties.
 Polyglycolic Acid Suture is a synthetic,
absorbable, sterile, surgical suture .

42.  Polyglycolic Acid Suture has been found to be
non-antigenic, non-pyrogenic and elicit only mild
tissue reactivity during the absorption process.
 The absorption time for Polyglycolic Acid (PGA) is
60 to 90 days.
 Absorption of bio-absorbable suture occurs by
hydrolysis ; beginning with loss of tensile strength
followed by loss of mass.

43.  Polydioxanone or poly-p-dioxanone is a colourless,
crystalline, biodegradable polymer.
 Polydioxanone suture is an absorbable, sterile,
surgical suture composed of the polyester, poly (p-
dioxanone).
 Polydioxanone suture has been found to be non-
antigenic, non-pyrogenic, and elicits only minimal
tissue reactivity during the absorption process.

44.  Polydioxanone like suture are provided with a
good flexibility.
 The suture prepared with this material typically
lose half of their mechanical strength in about
three weeks and complete degradation takes
place in a time frame of around six months.

45.  Minimal tissue reaction. Does not support infection.
 Absorbed slowly over a period of 6 to 7 months, thus it
provides wound support for longer
 periods.
 Polydioxanone suture retain approximately 80% of initial
Tensile strength after 14 days of surgery.
 Smooth, pliable and minimal memory.
 Dyed Dark Blue coloured for easy identification during
Surgery.

51.  Staples are formed from highquality stainless steel and
are available in regular and wide sizes.
 Staples are composed of -
(1) a crossmember that lays on the surface of the skin
perpendicular to the wound,
(2) legs that are vertically placed in the skin,
(3) tips that secure the staple parallel to the
crossmember.
 Staples are relatively easy to place and may shorten
the closure time by 70-80%.

52.  The primary utility of staples is in the closure of
wounds under high tension on the trunk,
extremities, and scalp.
 They are also used to secure split thickness skin
grafts.
 They are not used in delicate tissues or wounds in
finely contoured areas, over bony prominences, or
in highly mobile areas.

54.  Tapes are strips of microporous nonocclusive material (eg,
paper, plastic, rayon fabric) backed by a thin film of acrylic
polymer adhesive.
 They are useful as an adjunct to or a substitute for other
wound closure materials.
 Although they are used most often to reinforce a wound
after the removal of sutures or staples, they can also be
used alone for wounds that are small, nonexudative, and
under minimal tension.

55.  The advantages of tapes include ease of use, comfort
to the patient, and avoidance of tissue strangulation,
infection, and crosshatch marks.
 Followup visits for removal are not necessary.
 Allergic reaction to the adhesive is uncommon.
 Disadvantages include limited wound eversion,
imprecise wound edge approximation, and inconsistent
adhesion.

56.  Tapes have little usefulness in hairy or highly
mobile areas.
 Moisture, soap, and wound exudate decrease the
duration of tape adhesion.
 Commonly available products include
- SteriStrip Skin Closures (3M),
- Cover Strip II (Beiersdorf), and
- ProxiStrip Skin Closures (Ethicon).

57.  Cyanoacrylates for use in surgery have been available
.
 They polymerize in an exothermic reaction on contact
with fluid to form a 3-dimensional, strong, flexible
bond, with uses comparable to those of 5 0
monofilament nylon.
 Octylcyanoacrylate and N butyl2cyanoacrylate are
useful for the closure of simple lacerations in children
and uncooperative patients.

58.  They are also useful for the closure of incisions under
casts or in cases in which followup is difficult.
 They are not for use in areas that are highly mobile or
subject to friction (eg, over joints,hands, feet).
 Both cyanoacrylates are quick and easy to apply,
requiring only one-tenth to one-fourth of the time
required for suture placement.

59.  They may also be used to reinforce incisions
closed with suture or staples, as they provide an
antimicrobial and waterproof coating, but repeated
washing removes the adhesive in a few days.
 The cosmetic outcome is good, and no
postoperative visit is required for removal.